diff --git a/.github/workflows/deployJB2.yml b/.github/workflows/deployJB2.yml
new file mode 100644
index 00000000..9b16f3a9
--- /dev/null
+++ b/.github/workflows/deployJB2.yml
@@ -0,0 +1,48 @@
+# This file was created automatically with `myst init --gh-pages` 🪄 💚
+# Ensure your GitHub Pages settings for this repository are set to deploy with **GitHub Actions**.
+
+name: MyST GitHub Pages Deploy
+on:
+ push:
+ # Runs on pushes targeting the default branch
+ branches: [JB2]
+env:
+ # `BASE_URL` determines, relative to the root of the domain, the URL that your site is served from.
+ # E.g., if your site lives at `https://mydomain.org/myproject`, set `BASE_URL=/myproject`.
+ # If, instead, your site lives at the root of the domain, at `https://mydomain.org`, set `BASE_URL=''`.
+ BASE_URL: /${{ github.event.repository.name }}
+
+# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
+permissions:
+ contents: read
+ pages: write
+ id-token: write
+# Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
+# However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
+concurrency:
+ group: 'pages'
+ cancel-in-progress: false
+jobs:
+ deploy:
+ environment:
+ name: github-pages
+ url: ${{ steps.deployment.outputs.page_url }}
+ runs-on: ubuntu-latest
+ steps:
+ - uses: actions/checkout@v4
+ - name: Setup Pages
+ uses: actions/configure-pages@v3
+ - uses: actions/setup-node@v4
+ with:
+ node-version: 18.x
+ - name: Install MyST
+ run: npm install -g mystmd
+ - name: Build HTML Assets
+ run: myst build --html
+ - name: Upload artifact
+ uses: actions/upload-pages-artifact@v3
+ with:
+ path: './_build/html'
+ - name: Deploy to GitHub Pages
+ id: deployment
+ uses: actions/deploy-pages@v4
diff --git a/book/Folderwalker.ipynb b/Folderwalker.ipynb
similarity index 100%
rename from book/Folderwalker.ipynb
rename to Folderwalker.ipynb
diff --git a/book/Readme.md b/book/Readme.md
deleted file mode 100644
index a49fe70d..00000000
--- a/book/Readme.md
+++ /dev/null
@@ -1,3 +0,0 @@
-# Readme
-
-testfile
\ No newline at end of file
diff --git a/book/book/0 introduction/About.md b/book/book/0 introduction/About.md
index 17d8c0e2..6c867757 100644
--- a/book/book/0 introduction/About.md
+++ b/book/book/0 introduction/About.md
@@ -3,8 +3,8 @@
This book started off as a collection of pdf's from the '90s. We realised this was a valuable but static and outdated archive. We envisioned an updated online and dynamic repository of physics demonstrations which is accessible to all. By utilizing [GitHub](https://github.com) we would enable others to contribute, allow them to offer suggestions, fix bugs, while maintaining version control and ensuring quality. Our ultimate goal was to create a ‘living’, ‘ever-growing’ repository where the quality of the demonstrations can be continuously enhanced through active contributions from fellow educators, see {ref}`fig_infograph`.
```{figure} Infographic.png
-:width: 60%
-:name: fig_infograph
+:width: 100%
+:label: fig_infograph
Our approach to creating a living, ever-growing repository.
```
@@ -17,10 +17,10 @@ We consider the book not finished, as it is intended as an ever expanding reposi
## Your contribution
You can contribute to this book in various ways:
-1. Enhance the quality by adding comments and/or suggestions using the issue button below the button.
+1. Enhance the quality by adding comments and/or suggestions using the feedback button button.
2. Add content
-If you spot a typo, if something is not clear, or anything needs to be adjusted, click the button at the top of the screen and open an issue by clicking on the {fa}`lightbulb` button. (You need to have a github account though). We then receive a notification of your query, and we will address the issue as soon as possible.
+If you spot a typo, if something is not clear, or anything needs to be adjusted, click either the feedback button or the edit this page button at the top of the screen and open an issue. (You need to have a github account though). We then receive a notification of your query, and we will address the issue as soon as possible.
If you want to add your material, you can do so by contacting us. You can become a team member of the github repository and are allowed to add materials. If you are interested in how this works, see the [teachbooks manual](https://teachbooks.io/manual/workflows/collaboration.html) on the matter.
@@ -45,22 +45,30 @@ All drawings have been made by Hanna den Hartog. The videos were mainly recorded
## Contact
-Delft University of Technology
+````{grid} 1 1 3 3
+```{card} Delft University of Technology
Faculty of Applied Sciences
Department: Imaging Physics
Group: Science & Engineering Education
+```
-R. Haaksman
+```{card} R. Haaksman
Room: A162
Lorentzweg 1
2628 CJ Delft
The Netherlands
E-mail: R.P.H.Haaksman_at_TUDelft.nl
+::{figure} ../../figures/Ron.jpg
+::
+```
-F. Pols
+```{card} F. Pols
Room: A005
Lorentzweg 1
2628 CJ Delft
The Netherlands
E-mail: c.f.j.pols_at_tudelft.nl
-
+::{figure} ../../figures/pols.jpg
+::
+```
+````
\ No newline at end of file
diff --git a/book/book/0 introduction/Videos.md b/book/book/0 introduction/Videos.md
index 8b367521..2ad82088 100644
--- a/book/book/0 introduction/Videos.md
+++ b/book/book/0 introduction/Videos.md
@@ -1,687 +1,188 @@
# Videos
-
-
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-
+```{iframe} https://www.youtube.com/embed/YDBr1Lof_mI?si=RhTC31XHv-6gL4Kl
+```
+
+
+```{iframe} https://www.youtube.com/embed/gkH8Ex7yCb0?si=QKnOiUn7372H9vz_
+```
+
+```{iframe} https://www.youtube.com/embed/0m_dNR5KPuU?si=S715TrB2Vlc-zVdl
+```
+
+```{iframe} https://www.youtube.com/embed/2lsnQpFVnKQ?si=0lnTm9o0Aaor1f_c
+```
+
+```{iframe} https://www.youtube.com/embed/5k6pqTMEdKg?si=oNCvgrScaGwPgZxO
+```
+
+```{iframe} https://www.youtube.com/embed/6L10s6KvmNU?si=A2JxCUcctCAhYQ5b
+```
+
+```{iframe} https://www.youtube.com/embed/BSclXCB8nKc?si=tr-6ImnEZfDLtoIo
+```
+
+```{iframe} https://www.youtube.com/embed/FBIW7GdcKgU?si=4jik0LCy74sTY5LB
+```
+
+```{iframe} https://www.youtube.com/embed/LF3kxiy4UBI?si=oX-Pm0N3wQh7UDjX
+```
+
+```{iframe} https://www.youtube.com/embed/OqKIJ7Eq-B8?si=UD4uQgNZmcKYRZiD
+```
+
+```{iframe} https://www.youtube.com/embed/PmLqxyRhAvI?si=1mPK_6xDiM70t476
+```
+
+```{iframe} https://www.youtube.com/embed/RtBxZOIIxUE?si=gthG5-bqSC7lWNce
+```
+
+```{iframe} https://www.youtube.com/embed/TpvL20gy_bQ?si=E_omtbgGepdnpCPd
+```
+
+```{iframe} https://www.youtube.com/embed/URo-_ozbO18?si=RkoUfOX2rN3n9rqg
+```
+
+```{iframe} https://www.youtube.com/embed/UqNgZtQOqxc?si=BYJG3-xoJcGA5RsS
+```
+
+```{iframe} https://www.youtube.com/embed/X_dbrEpEMAs?si=8kIqSCjdKOUtVOU5
+```
+
+```{iframe} https://www.youtube.com/embed/YJhLewieVRI?si=AElIL0brw4ioeyTo
+```
+
+```{iframe} https://www.youtube.com/embed/YQAKQVE3gqk?si=MBSepn730SyqXOce
+```
+
+```{iframe} https://www.youtube.com/embed/_F9WF_3cXOY?si=hlRLTHIq3KCBRdMD
+```
+
+```{iframe} https://www.youtube.com/embed/bFp8MVOZZ5U?si=tIfsC0bIuZWWaZXQ
+```
+
+```{iframe} https://www.youtube.com/embed/diKayHPdg-o?si=H4jqeJCXmsjAfZYW
+```
+
+```{iframe} https://www.youtube.com/embed/eOxM9o7fhyI?si=YCGi78FfmZej0TAS
+```
+
+```{iframe} https://www.youtube.com/embed/enrU1xcXB8o?si=FoEwhBydM4p1t-oD
+```
+
+```{iframe} https://www.youtube.com/embed/exaFE_NZqcE?si=Qv0CtuOgX3GKw8e7
+```
+
+```{iframe} https://www.youtube.com/embed/hAxUzg58ZPI?si=CNl-GIYfIkbCi1h2
+```
+
+```{iframe} https://www.youtube.com/embed/mt9k6Xhb_PI?si=kPiQMt8dxbhJ7vy8
+```
+
+```{iframe} https://www.youtube.com/embed/pQoVApmwdNY?si=xM65rjpKTJKm_dpN
+```
+
+```{iframe} https://www.youtube.com/embed/rOs8GeF2Az8?si=IScfb5czYTc6WySH
+```
+
+```{iframe} https://www.youtube.com/embed/tT_4qx6vL-U?si=mAmqaIo4XJbwLwF2
+```
+
+```{iframe} https://www.youtube.com/embed/ulluSisk8sY?si=OQDe7bK3c-FscU73
+```
+
+```{iframe} https://www.youtube.com/embed/xeskVzH6CWQ?si=TOEmxa5IxhrZCtyc
+```
+
+```{iframe} https://www.youtube.com/embed/yTNxj_2iOc4?si=FT1tVAM85De71-Lu
+```
+
+```{iframe} https://www.youtube.com/embed/-HP7HtscYoc?si=lxGWa56vZrWg9Uf1
+```
+
+```{iframe} https://www.youtube.com/embed/0m_dNR5KPuU?si=jUXUMhnmKAJ3UBmf
+```
+
+```{iframe} https://www.youtube.com/embed/3Z4XlAOfLHU?si=JtXd95eKo60muiod
+```
+
+```{iframe} https://www.youtube.com/embed/3Z4XlAOfLHU?si=dGmJHyP1_s8gK9-Y
+```
+
+```{iframe} https://www.youtube.com/embed/4ZKzIHO-o18?si=F3NJzcfT9qWFOmaM
+```
+
+```{iframe} https://www.youtube.com/embed/6407mEoBnoc?si=TN1DF9IZS0krLNhy
+```
+
+```{iframe} https://www.youtube.com/embed/7oQcZhSoaPc?si=E9OjfBVXQhsPh4fM
+```
+
+```{iframe} https://www.youtube.com/embed/8Qdkv0y7fFw?si=vVCM4Kh5RulQ7HD4
+```
+
+```{iframe} https://www.youtube.com/embed/8tD93kUjvnk?si=mBpgnwuE_BOYxMeq
+```
+
+```{iframe} https://www.youtube.com/embed/CwEtNIKSpgw?si=kW0gLhwYfTybhISO
+```
+
+```{iframe} https://www.youtube.com/embed/EutntrR6P5E?si=VnCF6d6sR37rEBOn
+```
+
+```{iframe} https://www.youtube.com/embed/HSoC5pDBrks?si=XSiHsDulWpSCvACY
+```
+
+```{iframe} https://www.youtube.com/embed/Qyl9SfLNI3Y?si=8tzqJEx4UwO62ONt
+```
+
+```{iframe} https://www.youtube.com/embed/Sm8McbLyKos?si=2Gz-ywm19zM4dUl6
+```
+
+```{iframe} https://www.youtube.com/embed/WsPxsf9Npsk?si=wW1m5pQPoSp4ho3H
+```
+
+```{iframe} https://www.youtube.com/embed/_OfXNZzgFr4?si=adsBQ7dZleDPpNUT
+```
+
+```{iframe} https://www.youtube.com/embed/bDqfNBUHDF8?si=YUVFE53U_LVfrhzX
+```
+
+```{iframe} https://www.youtube.com/embed/chdQ4mHDZxg?si=rZraoVMS9Pr7gPBX
+```
+
+```{iframe} https://www.youtube.com/embed/e6Vwg-fTCdk?si=KkNqwyGsiIvkP3sq
+```
+
+```{iframe} https://www.youtube.com/embed/fFKDbYfUG7Y?si=wujcYRhkdCKBNAw0
+```
+
+```{iframe} https://www.youtube.com/embed/oTW4W_bmDe8?si=cljud_mpyRoq-c_H
+```
+
+```{iframe} https://www.youtube.com/embed/qOdcNDp0MVA?si=j8q8t-9WpmV4GNtE
+```
+
+```{iframe} https://www.youtube.com/embed/qb1cI2omZ4Y?si=gFBSYD3xObdyUo23
+```
+
+```{iframe} https://www.youtube.com/embed/sYquu44EjyM?si=wBHbDZGIjsaYCxlq
+```
+
+```{iframe} https://www.youtube.com/embed/sqekFe3OHYo?si=qUbX-nqCOMq4QCBF
+```
+
+```{iframe} https://www.youtube.com/embed/uzSy8geHbWw?si=Oswn7970XNLJPlgI
+```
+
+```{iframe} https://www.youtube.com/embed/v4ecijniYFo?si=wmq_vKpO8_tPH3mH
+```
+
+```{iframe} https://www.youtube.com/embed/vePptER5zUc?si=UgN5kZFlR_NNiTvR
+```
+
+```{iframe} https://www.youtube.com/embed/wIG1XiLKNBc?si=o6nN7plyiOHrJzPB
+```
+
+```{iframe} https://www.youtube.com/embed/x24R0ZDXmJU?si=KInmmw8Qho4arsZ_
+```
diff --git a/book/book/0 introduction/demolab.md b/book/book/0 introduction/demolab.md
index 8231230a..7e046807 100644
--- a/book/book/0 introduction/demolab.md
+++ b/book/book/0 introduction/demolab.md
@@ -20,9 +20,8 @@ We consider our ***Demonstration Room*** as a "shop" and we "sell" our demonstra
7. we know what is commercially available
```{figure} ../../figures/Ron.jpg
----
-width: 70%
----
+:width: 70%
+
Ron Haaksman
```
@@ -50,9 +49,8 @@ We propose demonstrations to the professors and in consultation with them we sel
Currently (2025) we present around 300 demonstrations every year and this number is still increasing, because more professors see and experience the benefits of our services. Moreover also other faculties of our Technical University Delft and teachers from outside our university have found their way to our demonstration facility. Our Demonstration Room is a booming business!
```{figure} ../../figures/pols.jpg
----
-width: 70%
----
+:width: 70%
+
Freek Pols
```
@@ -92,18 +90,8 @@ These studies show that students who passively observe demonstrations understand
At our department we apply the ***predict-method*** as much as possible. (The discuss-method requires too much time in our way of demonstrating). In the large lecture halls we question the prediction of the students before showing the demonstration. After a couple of minutes a multiple choice prediction is then presented to them. Then we show the demonstration and a short discussion follows.
-
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/yJ2Qu7IOlDs?si=bVn2oxlUtIxl3CXi
+```
## References
```{bibliography}
diff --git a/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2001 Hookes Law/1A2001.md b/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2001 Hookes Law/1A2001.md
index 81aef006..e5b16044 100644
--- a/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2001 Hookes Law/1A2001.md
+++ b/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2001 Hookes Law/1A2001.md
@@ -14,11 +14,10 @@ This demonstration shows Hooke's law. However, the focus is on taking measuremen
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: demo1A2001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: demo1A2001_figure_0
+
.
```
diff --git a/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2002 Determining g/1A2002.md b/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2002 Determining g/1A2002.md
index c4e0700d..7601761a 100644
--- a/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2002 Determining g/1A2002.md
+++ b/book/book/1 mechanics/1A measurement/1A20 Error and Accuracy/1A2002 Determining g/1A2002.md
@@ -1,9 +1,14 @@
+---
+kernelspec:
+ name: python3
+ display_name: 'Python 3'
+---
# 02 Determining g, with precision
## Aim
-This [demonstration from ShowthePhysics](https://interactivetextbooks.tudelft.nl/showthephysics/demos/demo73/demo73.html) {cite:t}`pols2024show` introduces students to the ideas of measurement uncertainty.
+This [demonstration from ShowthePhysics](https://interactivetextbooks.tudelft.nl/showthephysics/demos/demo73/demo73.html) [@https://doi.org/10.59490/tb.101] introduces students to the ideas of measurement uncertainty.
## Subjects
@@ -12,11 +17,10 @@ This [demonstration from ShowthePhysics](https://interactivetextbooks.tudelft.nl
## Diagram
-```{figure} figures/figure_1.png
----
-width: 70%
-name: demo1A2002/figure_1
----
+```{figure} figures/figure_1.jpg
+:width: 70%
+:label: demo1A2002_figure_1
+
.
```
@@ -84,7 +88,7 @@ $$
\left(\frac{\mu_g}{g}\right)^2 = \left(\frac{\mu_H}{H}\right)^2 + 4 \left(\frac{\mu_{\Delta t}}{\Delta t}\right)^2
$$
-The uncertainty is always given with only one significant figure. The final answer is presented with the same decimal digit (e.g., $9.8 \pm 0.3 \text{m}/\text{s^2}$).
+The uncertainty is always given with only one significant figure. The final answer is presented with the same decimal digit (e.g., $9.8 \pm 0.3 \text{m}/\text{s}^2$).
diff --git a/book/book/1 mechanics/1A measurement/1A40 Vectors/1A4001 Cross Product/1A4001.md b/book/book/1 mechanics/1A measurement/1A40 Vectors/1A4001 Cross Product/1A4001.md
index 1a578b67..d3a41866 100644
--- a/book/book/1 mechanics/1A measurement/1A40 Vectors/1A4001 Cross Product/1A4001.md
+++ b/book/book/1 mechanics/1A measurement/1A40 Vectors/1A4001 Cross Product/1A4001.md
@@ -14,11 +14,10 @@ To visualize the result of a cross product of two vectors.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1A4001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1A4001_figure_0
+
.
```
@@ -32,13 +31,12 @@ name: 1A4001/figure_0
## Presentation
* Rotate the screw into the direction $A \rightarrow B$. The screw moves into the direction of the result of the cross product of these two vectors. Rotating the screw in the opposite direction shows that the cross product vector points in the other direction.
-* The small white model is used in case of explaining Coriolis force in combination with a globe (see {numref}`Figure {number} <1A4001/figure_1>`).
+* The small white model is used in case of explaining Coriolis force in combination with a globe (see {numref}`Figure {number} <1A4001_figure_1>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1A4001_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1A4001/figure_1
----
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4001 Center of Mass/1D4001.md b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4001 Center of Mass/1D4001.md
index 1b72e637..879fd8e9 100644
--- a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4001 Center of Mass/1D4001.md
+++ b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4001 Center of Mass/1D4001.md
@@ -13,11 +13,10 @@ To show that the centre of mass does not change when only internal forces act.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: demo1D4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: demo1D4001_figure_0.png
+
Diagram of the experimental set-up
```
@@ -26,7 +25,7 @@ Diagram of the experimental set-up
* Track (2.2m, PASCO ME-9452), levelled.
* Two carts (PASCO ME-9454).
-* Bent rail track on frame, with "ball catcher" (plastic coffee cup) and a pointer fixed to it (see {numref}`Figure {number} `). The bent rail track is fixed firmly to the two carts. Ensure that the two carts are neatly aligned.
+* Bent rail track on frame, with "ball catcher" (plastic coffee cup) and a pointer fixed to it (see {numref}`Figure {number} `). The bent rail track is fixed firmly to the two carts. Ensure that the two carts are neatly aligned.
* Steel ball ($m=1 \mathrm{~kg}$).
* Graduated ruler, $l=1 \mathrm{~m}$.
* Small wooden beam.
@@ -40,25 +39,15 @@ Diagram of the experimental set-up
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/RtBxZOIIxUE?si=gthG5-bqSC7lWNce
+```
The Diagram is shown to the students. Then the mass of the cart-assembly is measured by the balance ($4 \mathrm{~kg}$) and also that of the steel ball ($1 \mathrm{~kg}$). Next, the centre of mass of the cart-assembly is determined by balancing this assembly on the small wooden beam. Then the assembly is set at rest in the middle of the levelled cart-track, and the pointer is fixed to the assembly in its centre of mass. Furthermore, this pointer position is marked on the table by placing a piece of chalk upright.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: demo1D4001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: demo1D4001_figure_1.png
+
Schematic representation of the experimental setup
```
@@ -69,9 +58,9 @@ When the ball is caught, the whole assembly is immediately at rest. However, the
### Explanation
-Our steel ball has a mass of $1 \mathrm{~kg}$. The cart-assembly (with carts, track, and cup, etc.) has a mass of $4 \mathrm{~kg}$. With our starting position at $33 \mathrm{~cm}$ away from the point of reference, this gives a sketch of the situation as shown in the first picture of {numref}`Figure {number} `.
+Our steel ball has a mass of $1 \mathrm{~kg}$. The cart-assembly (with carts, track, and cup, etc.) has a mass of $4 \mathrm{~kg}$. With our starting position at $33 \mathrm{~cm}$ away from the point of reference, this gives a sketch of the situation as shown in the first picture of {numref}`Figure {number} `.
-Calculating the distances $x$ and $y$ gives the displacement of the cart-assembly: With $m$ being the mass of the steel ball and $4 m$ the mass of the cart-assembly, the centre of mass is at the position indicated by the dotted line, because by definition the centre of mass is positioned at $R=\frac{m_{1} r_{1}+m_{2} r_{2}}{m_{1}+m_{2}}$, relative to some origin. When that origin is taken at the dotted line, so $R=0$, we have: $R=\frac{1(x-.33)+4(x)}{1+4}=0$, making $x=6.6 \mathrm{~cm}$. When the steel ball is released, no external forces act upon it, meaning that the centre of mass will not move. The bottom picture in {numref}`Figure {number} ` shows the situation at the end and the displacement of the steel ball and cart-assembly.
+Calculating the distances $x$ and $y$ gives the displacement of the cart-assembly: With $m$ being the mass of the steel ball and $4 m$ the mass of the cart-assembly, the centre of mass is at the position indicated by the dotted line, because by definition the centre of mass is positioned at $R=\frac{m_{1} r_{1}+m_{2} r_{2}}{m_{1}+m_{2}}$, relative to some origin. When that origin is taken at the dotted line, so $R=0$, we have: $R=\frac{1(x-.33)+4(x)}{1+4}=0$, making $x=6.6 \mathrm{~cm}$. When the steel ball is released, no external forces act upon it, meaning that the centre of mass will not move. The bottom picture in {numref}`Figure {number} ` shows the situation at the end and the displacement of the steel ball and cart-assembly.
Calculating again the position of the centre of mass in the same way
diff --git a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4002 Center of Rotation/1D4002.md b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4002 Center of Rotation/1D4002.md
index 3fbc503d..59d4f458 100644
--- a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4002 Center of Rotation/1D4002.md
+++ b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4002 Center of Rotation/1D4002.md
@@ -13,25 +13,22 @@ To show that a free rotating body rotates around its centre of mass.
## Diagram
-```{figure} figures/figure_1D40.02a.jpg
----
-width: 70%
-name: demo1D4002/figure_0
----
+```{figure} figures/figure_1D40.02a.jpg
+:width: 70%
+:label: demo1D4002_figure_0
+
.
```
-```{figure} figures/figure_1D40.02b.jpg
----
-width: 70%
-name: demo1D4002/figure_1D4002b
----
+```{figure} figures/figure_1D40.02b.jpg
+:width: 70%
+:label: demo1D4002_figure_1D4002b
+
.
```
-```{figure} figures/figure_1D40.02c.jpg
----
-width: 70%
-name: demo1D4002/figure_1D4002c
----
+```{figure} figures/figure_1D40.02c.jpg
+:width: 70%
+:label: demo1D4002_figure_1D4002c
+
.
```
@@ -46,25 +43,24 @@ name: demo1D4002/figure_1D4002c
## Presentation
-The two spheres, connected by a light stick, are balanced (see {numref}`Figure {number} `) to show where the centre of mass ($\mathrm{CM}$) is located. The location of the $\mathrm{CM}$ divides the distance ( $d$ ) between the two centres of the spheres in roughly $\frac{1}{3} d$ and $\frac{2}{3} d$.
+The two spheres, connected by a light stick, are balanced (see {numref}`Figure {number} `) to show where the centre of mass ($\mathrm{CM}$) is located. The location of the $\mathrm{CM}$ divides the distance ( $d$ ) between the two centres of the spheres in roughly $\frac{1}{3} d$ and $\frac{2}{3} d$.
-The system of two spheres connected by a twisted rubber band (see {numref}`Figure {number} ` and Remarks) is placed on the gridboard, and then left by itself. The system begins to rotate as the twisted rubber band unwinds. The system rotates around a fixed point. This can be recognized as the $\mathrm{CM}$. This can be related to the first part of the demonstration. Note that during the rotation, the distance between the spheres increases, but its centre of rotation keeps the ratio $\frac{1}{3}:\frac{2}{3}$!
+The system of two spheres connected by a twisted rubber band (see {numref}`Figure {number} ` and Remarks) is placed on the gridboard, and then left by itself. The system begins to rotate as the twisted rubber band unwinds. The system rotates around a fixed point. This can be recognized as the $\mathrm{CM}$. This can be related to the first part of the demonstration. Note that during the rotation, the distance between the spheres increases, but its centre of rotation keeps the ratio $\frac{1}{3}:\frac{2}{3}$!
## Explanation
As no external forces are acting, the $\mathrm{CM}$ has to remain at its position on the board according to Newton's first law. (Note: When the system rotates around any other point but the $\mathrm{CM}$, the $\mathrm{CM}$ performs a rotation, and an external torque should be needed for that.)
-```{figure} figures/figure_1.png
----
-width: 70%
-name: demo1D4002/figure_1
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: demo1D4002_figure_1
+
.
```
-The body rotates around an axis perpendicular to $d$. When no external forces are acting, the angular momentum vector $\vec{L}$ remains constant. The body in our demonstration consists of two masses: $m_{1}$ and $m_{2}$ (see {numref}`Figure {number} `a).
+The body rotates around an axis perpendicular to $d$. When no external forces are acting, the angular momentum vector $\vec{L}$ remains constant. The body in our demonstration consists of two masses: $m_{1}$ and $m_{2}$ (see {numref}`Figure {number} `a).
$$
\begin{aligned}
@@ -73,9 +69,9 @@ $$
\end{aligned}
$$
-The axis of rotation characterizes itself by the fact that, at any position on this axis, $\vec{L}$ will have the same magnitude and direction (at $O^{'}$ the horizontal components of $L_{1 a}$ and $L_{2 a}$ cancel, and their vertical components add up to $\vec{L}$: see Sources). This means that only one axis of rotation is possible. When, for instance, an axis of rotation is chosen passing through the centre of $\mathrm{m}_{1}$, then the total angular momentum adds up to $L_{2 b}$ (see {numref}`Figure {number} ` b). And so, being constant in magnitude, its direction constantly changes (describing a cone). Such a situation needs an external torque.
+The axis of rotation characterizes itself by the fact that, at any position on this axis, $\vec{L}$ will have the same magnitude and direction (at $O^{'}$ the horizontal components of $L_{1 a}$ and $L_{2 a}$ cancel, and their vertical components add up to $\vec{L}$: see Sources). This means that only one axis of rotation is possible. When, for instance, an axis of rotation is chosen passing through the centre of $\mathrm{m}_{1}$, then the total angular momentum adds up to $L_{2 b}$ (see {numref}`Figure {number} ` b). And so, being constant in magnitude, its direction constantly changes (describing a cone). Such a situation needs an external torque.
-In our demonstration, there is no external torque, and the sphere-system rotates around an axis somewhere between the two spheres ({numref}`Figure {number} `). At $O$, $\vec{L}=\vec{R}_{1} \times m_{1} \vec{v}_{1}+\vec{R}_{2} \times m_{2} \vec{v}_{2}$, directed along the axis of rotation. At $O^{'}$, the horizontal components of $L_{1}$ and $L_{2}$ need to cancel in order to keep $L$ along the axis of rotation.
+In our demonstration, there is no external torque, and the sphere-system rotates around an axis somewhere between the two spheres ({numref}`Figure {number} `). At $O$, $\vec{L}=\vec{R}_{1} \times m_{1} \vec{v}_{1}+\vec{R}_{2} \times m_{2} \vec{v}_{2}$, directed along the axis of rotation. At $O^{'}$, the horizontal components of $L_{1}$ and $L_{2}$ need to cancel in order to keep $L$ along the axis of rotation.
$$\left|\vec{L}_{1}\right|=\frac{R_{1} m_{1} v_{1}}{\cos \alpha}$$
@@ -91,11 +87,10 @@ $$L_{2 h}=m_{2} \omega R_{2} y L_{2 h}=m_{2} \omega R_{2} y$$
These two are equal when $m_{1} R_{1}=m_{2} R_{2}$, this holds when the axis of rotation passes through the $\mathrm{CM}$.
-```{figure} figures/figure_2.png
----
-width: 50%
-name: demo1D4002/figure_2
----
+```{figure} figures/figure_2.png
+:width: 50%
+:label: demo1D4002_figure_2
+
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4003 Students Centre of Mass/1D4003.md b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4003 Students Centre of Mass/1D4003.md
index 913445f9..f5a5bc2b 100644
--- a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4003 Students Centre of Mass/1D4003.md
+++ b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4003 Students Centre of Mass/1D4003.md
@@ -12,11 +12,10 @@ To show that the centre of mass ($CM$) will not move when only internal forces a
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: demo1D4003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: demo1D4003_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4004 Explosion/1D4004.md b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4004 Explosion/1D4004.md
index 4157fd24..a55ed57c 100644
--- a/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4004 Explosion/1D4004.md
+++ b/book/book/1 mechanics/1D 2D motion/1D40 Center of Mass/1D4004 Explosion/1D4004.md
@@ -12,22 +12,23 @@ To demonstrate that in an explosion, the centre of mass does not move.
## Diagram
-
-```{figure} figures/figure_1D40.04a.jpg
----
-width: 70%
-name: 1n2003/figure_1D40.04a.jpg
----
+
+````{figure}
+:label: 1n2003_figure_0.png
+```{figure} figures/figure_1D40.04a.jpg
+:width: 70%
+:label: 1n2003_figure_1D40.04a.jpg
+
.
```
-```{figure} figures/figure_1D40.04b.jpg
----
-width: 70%
-name: 1n2003/figure_1D40.04b.jpg
----
+```{figure} figures/figure_1D40.04b.jpg
+:width: 70%
+:label: 1n2003_figure_1D40.04b.jpg
+
.
```
+````
## Equipment
@@ -50,7 +51,7 @@ name: 1n2003/figure_1D40.04b.jpg
### Preparation
-Place the two supports of the cart track in the middle of the track, about $4 \mathrm{~cm}$ apart, to balance the track on the small table (see {numref}`Figure {number} <1n2003/figure_0.png>`). Use an air level to carefully balance the small table horizontally, then do the same for the track.
+Place the two supports of the cart track in the middle of the track, about $4 \mathrm{~cm}$ apart, to balance the track on the small table (see {numref}`Figure {number} <1n2003_figure_0.png>`). Use an air level to carefully balance the small table horizontally, then do the same for the track.
### Presentation
@@ -74,11 +75,10 @@ The centre of mass ($CM$) of a fixed number of particles is defined as the avera
$$R_{c m}=\frac{m_{1} x_{1}+m_{2} x_{2}}{m_{1}+m_{2}}$$
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2003/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2003_figure_1.png
+
.
```
@@ -88,28 +88,26 @@ Since $x=v t; m_{1} x_{1}+m_{2} x_{2}=0$, so $R_{CM}=0$ and $CM$ remains at the
***Extra.***
-When one cart hits the end stop ( $m_{2}$ in {numref}`Figure {number} <1n2003/figure_2.png>`), there is at that location a change of momentum $\Delta p=2 m v$ of the cart. The track experiences an impulse of $\left|\int_{0}^{\Delta t} F d t\right|=2 m v$. There is no external impulse imparted to the track, so this impulse must be balanced somewhere. Friction force at the support takes care for that $\left|\int_{0}^{\Delta t} F_{f} d t\right|$. And also: $F_{f}=-F$ (Newton 3).
+When one cart hits the end stop ( $m_{2}$ in {numref}`Figure {number} <1n2003_figure_2.png>`), there is at that location a change of momentum $\Delta p=2 m v$ of the cart. The track experiences an impulse of $\left|\int_{0}^{\Delta t} F d t\right|=2 m v$. There is no external impulse imparted to the track, so this impulse must be balanced somewhere. Friction force at the support takes care for that $\left|\int_{0}^{\Delta t} F_{f} d t\right|$. And also: $F_{f}=-F$ (Newton 3).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1n2003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1n2003/figure_2.png
----
.
```
-In {numref}`Figure {number} <1n2003/figure_2.png>`A this $F_{f}$ gives the whole assembly a velocity to the right, displacing $CM$ to the right. $CM$ will keep on moving to the right (Newton 1), increasing the unbalance more and more.
+In {numref}`Figure {number} <1n2003_figure_2.png>`A this $F_{f}$ gives the whole assembly a velocity to the right, displacing $CM$ to the right. $CM$ will keep on moving to the right (Newton 1), increasing the unbalance more and more.
## Remarks
-- When carts of different masses are placed on the balanced track, take care that their common centre of mass is placed right above the balanced point of the track (see {numref}`Figure {number} <1n2003/figure_3.png>`). When $m_{1}=2 m_{2}$, then $y=1 / 61$; when $m_{1}=3 m_{2}$, then $y=1 / 41$.
+- When carts of different masses are placed on the balanced track, take care that their common centre of mass is placed right above the balanced point of the track (see {numref}`Figure {number} <1n2003_figure_3.png>`). When $m_{1}=2 m_{2}$, then $y=1 / 61$; when $m_{1}=3 m_{2}$, then $y=1 / 41$.
+
+```{figure} figures/figure_3.png
+:width: 40%
+:label: 1n2003_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 40%
-name: 1n2003/figure_3.png
----
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5001 Going Round in Circles/1D5001.md b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5001 Going Round in Circles/1D5001.md
index be442da5..9584b04f 100644
--- a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5001 Going Round in Circles/1D5001.md
+++ b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5001 Going Round in Circles/1D5001.md
@@ -7,11 +7,10 @@ To see/feel the centripetal force.
* 1D50 Central Forces
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1d5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1d5001_figure_0.png
+
.
```
@@ -26,11 +25,10 @@ name: 1d5001/figure_0.png
## Presentation
The diagram shows the components and how to use them. By swinging the tube slightly, the mass $m_{1}$ begins to move in circles above your head. The demonstrator must swing $m_{1}$ at a specific frequency to balance the system.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1d5001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1d5001_figure_1.png
+
.
```
@@ -45,13 +43,12 @@ If time permits, the relationship between the variables in this demonstration ca
3. When half the rope length is used (shifting the paperclip), a higher frequency is needed to balance the system.
## Explanation
-Analysis shows that movement at a constant speed ( $v$ ) of a mass ( $m_{1}$ ) in a circle with radius $R$ can be described by $a_{c}=\frac{v^{2}}{r} \omega^{2} R$. In our demonstration the tension ( $T$ ) in the string provides the force needed for $a_{c}: T=m_{1} a_{c}$, and $m_{2} g=m_{1} a_{c} \Rightarrow a_{c}=\frac{m_{2}}{m_{1}} g$, (see {numref}`Figure {number} <1d5001/figure_2.png>`).
+Analysis shows that movement at a constant speed ( $v$ ) of a mass ( $m_{1}$ ) in a circle with radius $R$ can be described by $a_{c}=\frac{v^{2}}{r} \omega^{2} R$. In our demonstration the tension ( $T$ ) in the string provides the force needed for $a_{c}: T=m_{1} a_{c}$, and $m_{2} g=m_{1} a_{c} \Rightarrow a_{c}=\frac{m_{2}}{m_{1}} g$, (see {numref}`Figure {number} <1d5001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1d5001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1d5001/figure_2.png
----
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5002 Conical Pendulum/1D5002.md b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5002 Conical Pendulum/1D5002.md
index 8b8b2e1b..4f372f05 100644
--- a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5002 Conical Pendulum/1D5002.md
+++ b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5002 Conical Pendulum/1D5002.md
@@ -8,11 +8,10 @@ To show that the period of motion of a conical pendulum changes only noticeably
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1d5002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1d5002_figure_0.png
+
.
```
@@ -30,22 +29,21 @@ name: 1d5002/figure_0.png
2. Take the small simple pendulum by hand and make it swing conically. Gradually increase its speed. At very large angles, the increase in angular velocity becomes easily noticeable.
## Explanation
-Theory tells us that the period ( $T$ ) of a conical pendulum is given by $T=2 \pi \sqrt{\frac{l \cos \phi}{g}}$ (see {numref}`Figure {number} <1d5002/figure_1.png>`).
+Theory tells us that the period ( $T$ ) of a conical pendulum is given by $T=2 \pi \sqrt{\frac{l \cos \phi}{g}}$ (see {numref}`Figure {number} <1d5002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1d5002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1d5002/figure_1.png
----
.
```
So $T \propto \sqrt{\cos \phi}$
-The table in {numref}`Table {number} <1d5002/table1>` shows that from $0^{\circ}$ to $30^{\circ}, \sqrt{\cos \phi}$ only changes $7 \%$, while from $60^{\circ}$ to $89^{\circ}$ this change is about $82 \%$. So only at large angles $\phi$, $T$ changes noticeably.
+The table in {numref}`Table {number} <1d5002_table1>` shows that from $0^{\circ}$ to $30^{\circ}, \sqrt{\cos \phi}$ only changes $7 \%$, while from $60^{\circ}$ to $89^{\circ}$ this change is about $82 \%$. So only at large angles $\phi$, $T$ changes noticeably.
```{table} table
-:name: 1d5002/table1
+:label: 1d5002_table1
| $\varphi(\%)$ | $\sqrt{\cos \varphi}$ |
| :---: | :---: |
| 0 | 1 |
@@ -61,13 +59,12 @@ The table in {numref}`Table {number} <1d5002/table1>` shows that from $0^{\circ}
## Remarks
* When the pendulum is suspended vertically and not swinging, we have marked this central position on the table. The paper circles have a hole in their center so that it is easy to position them in the right place (hole and mark coincide).
- * Making the pendulum swing along the circumference of the paper circle needs some practice. Launch the suspended ball tangentially and give it a speed so that it just reaches a deflection equal to $R$ of the paper circle (see {numref}`Figure {number} <1d5002/figure_3.png>`).
+ * Making the pendulum swing along the circumference of the paper circle needs some practice. Launch the suspended ball tangentially and give it a speed so that it just reaches a deflection equal to $R$ of the paper circle (see {numref}`Figure {number} <1d5002_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1d5002_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1d5002/figure_3.png
----
.
```
diff --git a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5003 Centripetal Force/1D5003.md b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5003 Centripetal Force/1D5003.md
index 666f1d58..d2a04a07 100644
--- a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5003 Centripetal Force/1D5003.md
+++ b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5003 Centripetal Force/1D5003.md
@@ -8,11 +8,10 @@ To show an example of the centripetal force.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1d5003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1d5003_figure_0.png
+
.
```
@@ -27,31 +26,29 @@ name: 1d5003/figure_0.png
## Presentation
- Hold the conical beaker filled with water upside-down in your hands. The ping-pong ball floats directly above the rubber stopper. Start turning in a circle, and while turning, observe the behaviour of the ping-pong ball (see {numref}`Figure {number} <1d5003/figure_1.png>`).
+ Hold the conical beaker filled with water upside-down in your hands. The ping-pong ball floats directly above the rubber stopper. Start turning in a circle, and while turning, observe the behaviour of the ping-pong ball (see {numref}`Figure {number} <1d5003_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1d5003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1d5003/figure_1.png
----
.
```
The ping-pong ball is displaced towards you.
## Explanation
-The ping-pong ball, being completely immersed in water, experiences an upward buoyant force $F_u$ that is greater than its weight $m \cdot g$. The net force ($F_u - m \cdot g$) is directed upwards. The tension $T$ in the string prevents the ping-pong ball from floating upwards (see {numref}`Figure {number} <1d5003/figure_2.png>`a).
+The ping-pong ball, being completely immersed in water, experiences an upward buoyant force $F_u$ that is greater than its weight $m \cdot g$. The net force ($F_u - m \cdot g$) is directed upwards. The tension $T$ in the string prevents the ping-pong ball from floating upwards (see {numref}`Figure {number} <1d5003_figure_2.png>`a).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1d5003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1d5003/figure_2.png
----
.
```
-When turning around in circles, the ping-pong ball is forced to move in a circle. A centripetal force is needed for that. {numref}`Figure {number} <1d5003/figure_2.png>`b shows the new situation of equilibrium: the net upward force and tension are compensated by a centripetal force $F_{c}$. Any other position of the ping-pong ball is not a situation of equilibrium (drawing a free body diagram of the forces will show this).
+When turning around in circles, the ping-pong ball is forced to move in a circle. A centripetal force is needed for that. {numref}`Figure {number} <1d5003_figure_2.png>`b shows the new situation of equilibrium: the net upward force and tension are compensated by a centripetal force $F_{c}$. Any other position of the ping-pong ball is not a situation of equilibrium (drawing a free body diagram of the forces will show this).
## Remarks
* When an air bubble is trapped in the conical beaker filled with water, this bubble will behave in the same way as the ping-pong ball does.
diff --git a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5004 Force Field/1D5004.md b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5004 Force Field/1D5004.md
index 1a6fbf5d..e2e2c583 100644
--- a/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5004 Force Field/1D5004.md
+++ b/book/book/1 mechanics/1D 2D motion/1D50 Central Forces/1D5004 Force Field/1D5004.md
@@ -8,11 +8,10 @@ To introduce the concept of a (radial) force field.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1d5004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1d5004_figure_0.png
+
.
```
@@ -22,13 +21,12 @@ name: 1d5004/figure_0.png
* Steel ball.
## Presentation
- The steel ball is held out of the centre of the bowl and released. Then the overhead projector is switched on and the image of the steel ball is projected on the screen. The spectators see the ball move in a line from one side to the other, just like there is some spring that is continuously pulling the steel ball towards the centre. The line may rotate slowly in a plane, but all the time we can describe this movement as being caused by a force that is always directed towards a centre (see {numref}`Figure {number} <1d5004/figure_1.png>`).
+ The steel ball is held out of the centre of the bowl and released. Then the overhead projector is switched on and the image of the steel ball is projected on the screen. The spectators see the ball move in a line from one side to the other, just like there is some spring that is continuously pulling the steel ball towards the centre. The line may rotate slowly in a plane, but all the time we can describe this movement as being caused by a force that is always directed towards a centre (see {numref}`Figure {number} <1d5004_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1d5004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1d5004/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md
index 9008dd9a..efe3974e 100644
--- a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md
+++ b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md
@@ -7,36 +7,26 @@
* 1E10 (Moving Reference Frames)
* 1N20 (Conservation of Linear Momentum)
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/Oxte-YmnnHI?si=PzP00e48WqzlzpsX
+```
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e1001_figure_0.png
+
.
```
```{figure} figures/balls.jpg
----
+
figclass: margin
-width: 70%
-name: 1e1001/figure_X.png
----
+:width: 70%
+:label: 1e1001_figure_X.png
+
The Astro-superball
```
@@ -48,26 +38,16 @@ The Astro-superball
## Presentation
A superball of small mass is dropped and rebounds almost to its original height. Next, the small superball is held about $10~\mathrm{cm}$ above a larger superball. This combination is dropped simultaneously, and after striking the floor, the small ball launches upward and can reach a height up to nine times the original dropping height.
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/CwEtNIKSpgw?si=kW0gLhwYfTybhISO
+```
## Explanation
-Just before striking the floor, both balls have a velocity $v$ downward. Just after the combination hits the floor, the larger ball rebounds upward with a velocity $v$, while the smaller ball is still moving downward with a velocity $v$. This makes their relative speed $2v$ — the small ball is approaching the large ball at $2v$. If the collision between the balls is elastic, the smaller ball will rebound with a velocity of $2v$ relative to the larger ball, but in the opposite direction. Since the larger ball is moving upward at $v$, the small ball’s velocity relative to the floor becomes $v + 2v = 3v$ upward.(See {numref}`Figure {number} <1e1001/figure_1.png>`)
+Just before striking the floor, both balls have a velocity $v$ downward. Just after the combination hits the floor, the larger ball rebounds upward with a velocity $v$, while the smaller ball is still moving downward with a velocity $v$. This makes their relative speed $2v$ — the small ball is approaching the large ball at $2v$. If the collision between the balls is elastic, the smaller ball will rebound with a velocity of $2v$ relative to the larger ball, but in the opposite direction. Since the larger ball is moving upward at $v$, the small ball’s velocity relative to the floor becomes $v + 2v = 3v$ upward.(See {numref}`Figure {number} <1e1001_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e1001/figure_1.png
----
.
```
@@ -77,7 +57,7 @@ The small ball would have gone up with a velocity $v$ if it had just hit the flo
## Remarks
* Do not rest the table-tennis ball on the basketball and drop it in such a combination. When this is done, the table-tennis ball stays fixed to the basketball (aerodynamic reason), and for this demonstration, it is required that on hitting the ground, there is some distance between the two balls.
* It is recommended to practise the drop beforehand, especially to ensure that the small and large balls are released simultaneously.
-* An extension of the demonstration is to drop a stack of three or even more balls (See {numref}`Figure {number} <1e1001/figure_X.png>`). When a three-ball combination is dropped, the top ball approaches a maximum of 49 times the initial release height. In order to drop the Astroball-stack perfectly vertical, wet your fingers holding the stack and slowly let it slip away.
+* An extension of the demonstration is to drop a stack of three or even more balls (See {numref}`Figure {number} <1e1001_figure_X.png>`). When a three-ball combination is dropped, the top ball approaches a maximum of 49 times the initial release height. In order to drop the Astroball-stack perfectly vertical, wet your fingers holding the stack and slowly let it slip away.
* The experiment does not perform very well on a wooden floor.
diff --git a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1002 Galilean Cart/1E1002.md b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1002 Galilean Cart/1E1002.md
index 1a4470a1..27c56679 100644
--- a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1002 Galilean Cart/1E1002.md
+++ b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1002 Galilean Cart/1E1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e1002_figure_0.png
+
.
```
@@ -27,17 +26,16 @@ name: 1e1002/figure_0.png
## Presentation
- * One person sits on the cart, fills the funnel with salt while keeping the outlet closed with a finger, and then gives the funnel pendulum a deflection in the $x'$-direction. The demonstrator moves the cart with constant speed along the front of the lecture hall ($y$-direction). As soon as the cart moves at a constant speed, the person on the cart sets the pendulum swinging. A salt track is left on the floor of the lecture hall (see {numref}`Figure {number} <1e1002/figure_2.png>`). This track records the motion of the swinging funnel in the $x$-$y$ plane.
+ * One person sits on the cart, fills the funnel with salt while keeping the outlet closed with a finger, and then gives the funnel pendulum a deflection in the $x'$-direction. The demonstrator moves the cart with constant speed along the front of the lecture hall ($y$-direction). As soon as the cart moves at a constant speed, the person on the cart sets the pendulum swinging. A salt track is left on the floor of the lecture hall (see {numref}`Figure {number} <1e1002_figure_2.png>`). This track records the motion of the swinging funnel in the $x$-$y$ plane.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e1002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e1002_figure_1.png
+
.
```
- * The same demonstration is performed, but now with the funnel-pendulum swinging into the $y'$-direction. A second salt-track appears on the floor (see {numref}`Figure {number} <1e1002/figure_1.png>`).
+ * The same demonstration is performed, but now with the funnel-pendulum swinging into the $y'$-direction. A second salt-track appears on the floor (see {numref}`Figure {number} <1e1002_figure_1.png>`).
Again, the salt track shows the recording of the movement of the swinging funnel in the $x$-$y$ plane.
@@ -47,18 +45,17 @@ The results are discussed.
## Explanation
- The pendulum moves in the $x^{'}$-$y^{'}$-$z^{'}$-frame according to: $x^{'}=A \sin (\omega t+\phi)$; $y^{'}=0 ; z^{'}=0$. The writing on the ground in salt is in the $x-y-z$-frame. The $x^{'}-y^{'}-z^{'}-$ frame moves with a speed $\mathrm{V}$ into the $\mathrm{y}$-direction., so a point measured in the $x^{'}-$ $y^{'}-z^{'}$-frame will have an $y$-coordinate: $y=V t$. (see Figure2).
-- When the pendulum swings into the $y^{'}$-direction, the movements in the $x$-y-zframe will be: $y=V t+A \sin (\omega t+\phi) ; x=0$ and $z=0$ (see {numref}`Figure {number} <1e1002/figure_2.png>`).
+- When the pendulum swings into the $y^{'}$-direction, the movements in the $x$-y-zframe will be: $y=V t+A \sin (\omega t+\phi) ; x=0$ and $z=0$ (see {numref}`Figure {number} <1e1002_figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1e1002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1e1002_figure_2.png
+
.
```
## Remarks
- * As {numref}`Figure {number} <1e1002/figure_1.png>` makes clear, the difference between much - and little salt is more pronounced when $y=V t$ is steeper; that is at higher speeds of the cart.
+ * As {numref}`Figure {number} <1e1002_figure_1.png>` makes clear, the difference between much - and little salt is more pronounced when $y=V t$ is steeper; that is at higher speeds of the cart.
## Sources
* Mansfield, M and O'Sullivan, C., Understanding physics, pag. 173-174
diff --git a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1003 Shoot and Catch/1E1003.md b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1003 Shoot and Catch/1E1003.md
index 832589a9..e96e47a0 100644
--- a/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1003 Shoot and Catch/1E1003.md
+++ b/book/book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1003 Shoot and Catch/1E1003.md
@@ -8,11 +8,10 @@ To show that when a ball is shot vertically upward from a cart moving at a const
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e1003_figure_0.png
+
.
```
@@ -31,26 +30,24 @@ name: 1e1003/figure_0.png
4. Start the cart at the bottom of the incline. (If necessary, reposition the trip bracket.) Again, ask the students the same question. Give the cart a push uphill so that it travels past the trip bracket. The ball is launched and... caught again! It doesn't matter how fast the cart is moving or where on the track the bracket launches the ball — the launched ball is always caught again.
## Explanation
- 1. The cart and ball have the same horizontal component of velocity. The horizontal component of acceleration of both cart and ball is zero, so ball and cart remain aligned (see {numref}`Figure {number} <1e1003/figure_1.png>`).
+ 1. The cart and ball have the same horizontal component of velocity. The horizontal component of acceleration of both cart and ball is zero, so ball and cart remain aligned (see {numref}`Figure {number} <1e1003_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e1003/figure_1.png
----
.
```
2. When the cart is accelerating, it is still accelerating after the ball has been launched. But after launching, the ball is no longer accelerating in the horizontal direction, so it will lag behind the cart.
- 3. When the track is tilted, the cart and ball have the same component of acceleration parallel to the track (see {numref}`Figure {number} <1e1003/figure_2.png>`). Since they have the same initial parallel-component velocity and the same parallel-component acceleration, they will always keep the same parallel-component velocity. The ball will always be in line with the cart, perpendicular to the track, and it will be caught.
+ 3. When the track is tilted, the cart and ball have the same component of acceleration parallel to the track (see {numref}`Figure {number} <1e1003_figure_2.png>`). Since they have the same initial parallel-component velocity and the same parallel-component acceleration, they will always keep the same parallel-component velocity. The ball will always be in line with the cart, perpendicular to the track, and it will be caught.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1e1003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1e1003/figure_2.png
----
.
```
- 4. The same holds for the cart moving upward. So again see {numref}`Figure {number} <1e1003/figure_2.png>`.
+ 4. The same holds for the cart moving upward. So again see {numref}`Figure {number} <1e1003_figure_2.png>`.
## Remarks
* Catch the cart before it reaches the end stop on the track.
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2001 Coriolis/1E2001.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2001 Coriolis/1E2001.md
index 1c1e83f1..ead21b5c 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2001 Coriolis/1E2001.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2001 Coriolis/1E2001.md
@@ -9,11 +9,10 @@ To show a rather complicated rotation and how the Coriolis force and centripetal
* 1E30 (Coriolis Effect)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2001_figure_0
+
.
```
@@ -34,71 +33,65 @@ The sheet of paper is attached to the round metal plate using pieces of double-s
## Explanation
### 1. Explaining it from within the rotating frame of reference of the demonstrator:
- The demonstrator turns round, so he is in a rotating reference frame. In this rotating reference frame, every part of the sheet of paper has a specific velocity (see the four $\bar{v}$ ''s drawn in {numref}`Figure {number} <1e2001/figure_1>`).
-In a rotating reference frame every object moving with a certain velocity has to deal with Coriolis-force: $\bar{F}_{\text {cor }}=-2 m\left(\bar{\omega} \times \vec{v}^{'}\right)$ and with centrifugal force: $F_{c f}=-m \vec{\omega} \times(\bar{\omega} \times \vec{r})$, ( $r$ being the radius from the axis of the demonstrator to the piece of paper considered). We consider the four indicated parts of the rotating paper disk (see {numref}`Figure {number} <1e2001/figure_1>`):
-
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e2001/figure_1
----
+ The demonstrator turns round, so he is in a rotating reference frame. In this rotating reference frame, every part of the sheet of paper has a specific velocity (see the four $\bar{v}$ ''s drawn in {numref}`Figure {number} <1e2001_figure_1>`).
+In a rotating reference frame every object moving with a certain velocity has to deal with Coriolis-force: $\bar{F}_{\text {cor }}=-2 m\left(\bar{\omega} \times \vec{v}^{'}\right)$ and with centrifugal force: $F_{c f}=-m \vec{\omega} \times(\bar{\omega} \times \vec{r})$, ( $r$ being the radius from the axis of the demonstrator to the piece of paper considered). We consider the four indicated parts of the rotating paper disk (see {numref}`Figure {number} <1e2001_figure_1>`):
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e2001_figure_1
+
.
```
1. $v^{'}$ parallel to $\omega$, so $F_{cor}=0 ; F_{cf} \neq 0$.
-2. $v^{'}$ perpendicular to $\omega$; direction of $F_{\text {cor }}$ : see {numref}`Figure {number} <1e2001/figure_2>`A. This $F_{cor}$ adds to $F_{cf}$. In general, $F_{cor}>>F_{cf}$, so there is a large $F$ pointing outwards, in magnitude almost equal to $F_{cor}$. (See the result on point 2. in {numref}`Figure {number} <1e2001/figure_3>`).
+2. $v^{'}$ perpendicular to $\omega$; direction of $F_{\text {cor }}$ : see {numref}`Figure {number} <1e2001_figure_2>`A. This $F_{cor}$ adds to $F_{cf}$. In general, $F_{cor}>>F_{cf}$, so there is a large $F$ pointing outwards, in magnitude almost equal to $F_{cor}$. (See the result on point 2. in {numref}`Figure {number} <1e2001_figure_3>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1e2001_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1e2001/figure_2
----
.
```
3. $-v^{'}$ parallel to $\omega$, so $F_{\text {cor }}=0 ; \quad F_{c f} \neq 0$
-4. $v^{'}$ perpendicular to $\omega$; direction of $F_{c o r}$ see {numref}`Figure {number} <1e2001/figure_2>`B. $F_{c f} \neq 0 . F_{c o r}$ is opposing $F_{c f}$. In general, $F_{c o r} \gg>F_{c f}$, so there is a large $F$ pointing inward, in magnitude almost equal to $F_{\text {cor }}$. (See the result on point 4. in {numref}`Figure {number} <1e2001/figure_3>`.)
+4. $v^{'}$ perpendicular to $\omega$; direction of $F_{c o r}$ see {numref}`Figure {number} <1e2001_figure_2>`B. $F_{c f} \neq 0 . F_{c o r}$ is opposing $F_{c f}$. In general, $F_{c o r} \gg>F_{c f}$, so there is a large $F$ pointing inward, in magnitude almost equal to $F_{\text {cor }}$. (See the result on point 4. in {numref}`Figure {number} <1e2001_figure_3>`.)
+
+```{figure} figures/figure_3.png
+:width: 40%
+:label: 1e2001_figure_3
-```{figure} figures/figure_3.png
----
-width: 40%
-name: 1e2001/figure_3
----
.
```
### 2. Explaining it from the outside:
-In {numref}`Figure {number} <1e2001/figure_1>`, the entire sheet of paper rotates around the demonstrator's axis. The magnitude of $v'$ changes very little when the demonstrator starts turning with angular velocity $\omega$ around their axis (see the red arrows in {numref}`Figure {number} <1e2001/figure_4>`). We therefore consider the magnitude of $v'$ to remain constant.
+In {numref}`Figure {number} <1e2001_figure_1>`, the entire sheet of paper rotates around the demonstrator's axis. The magnitude of $v'$ changes very little when the demonstrator starts turning with angular velocity $\omega$ around their axis (see the red arrows in {numref}`Figure {number} <1e2001_figure_4>`). We therefore consider the magnitude of $v'$ to remain constant.
+
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 1e2001_figure_4
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 1e2001/figure_4
----
.
```
-However, due to the demonstrator’s angular velocity $\omega$, the direction of $v'$ at positions 2 and 4 changes appreciably. Forces are required to cause this change. {numref}`Figure {number} <1e2001/figure_5>` illustrates how $v'$ changes direction at positions 2 and 4.
+However, due to the demonstrator’s angular velocity $\omega$, the direction of $v'$ at positions 2 and 4 changes appreciably. Forces are required to cause this change. {numref}`Figure {number} <1e2001_figure_5>` illustrates how $v'$ changes direction at positions 2 and 4.
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 1e2001/figure_5
----
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 1e2001_figure_5
+
.
```
-The two $\Delta v$ vectors in {numref}`Figure {number} <1e2001/figure_5>` also indicate the directions of the forces required to cause these changes. However, no such forces are directly applied to these parts of the paper, since the paper is slack and flexible. To generate these forces within the paper, deformation is necessary. Consequently, the upper part bends outward while the lower part bends inward. These directions of deformation correspond to the distortions shown in {numref}`Figure {number}`.
+The two $\Delta v$ vectors in {numref}`Figure {number} <1e2001_figure_5>` also indicate the directions of the forces required to cause these changes. However, no such forces are directly applied to these parts of the paper, since the paper is slack and flexible. To generate these forces within the paper, deformation is necessary. Consequently, the upper part bends outward while the lower part bends inward. These directions of deformation correspond to the distortions shown in {numref}`Figure {number}`.
### 3. Explaining it with ω-vectors.
-There are two $\omega$-vectors in this demonstration: $\omega$ of the paper disk and $\omega$ of the demonstrator. In the demonstration these two add together (see {numref}`Figure {number} <1e2001/figure_6>`) to the green $\omega_{\text{TOTAL}}$. The rotating disk will orient itself to this new rotational vector.
+There are two $\omega$-vectors in this demonstration: $\omega$ of the paper disk and $\omega$ of the demonstrator. In the demonstration these two add together (see {numref}`Figure {number} <1e2001_figure_6>`) to the green $\omega_{\text{TOTAL}}$. The rotating disk will orient itself to this new rotational vector.
+
+```{figure} figures/figure_6.png
+:width: 70%
+:label: 1e2001_figure_6
-```{figure} figures/figure_6.png
----
-width: 70%
-name: 1e2001/figure_6
----
.
```
(Instead of using $\bar{\omega}$-vectors in this explanation, you can also use $\vec{L}$-vectors.)
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2002 Coriolis/1E2002.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2002 Coriolis/1E2002.md
index 1cd856e9..f0cdcc7a 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2002 Coriolis/1E2002.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2002 Coriolis/1E2002.md
@@ -9,11 +9,10 @@ To show the effect on an object moving with constant velocity in a rotating refe
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2002_figure_0.png
+
.
```
@@ -24,7 +23,7 @@ name: 1e2002/figure_0.png
- Ramp (made of a curved curtain rail).
- Steel ball, $r =3 \mathrm{~cm}$.
- Clamping material.
-- Two overhead sheets (see {numref}`Figure {number} <1e2002/figure_2.png>`A, B).
+- Two overhead sheets (see {numref}`Figure {number} <1e2002_figure_2.png>`A, B).
- Graduated arc $\left(360^{\circ}\right)$.
## Safety
@@ -39,13 +38,12 @@ name: 1e2002/figure_0.png
From the perspective of someone “living” on the rotating platform, the cause of the ball’s counterclockwise curvature is called the *Coriolis force*. (You will probably need to repeat this part of the demonstration to help your students clearly observe it.) When the board rotates counterclockwise, the ball’s curvature on the platform will be clockwise.
- Next the ramp is fixed to the rotating platform. Several directions of launching the steel ball can be shown then (see {numref}`Figure {number} <1e2002/figure_1.png>`).
+ Next the ramp is fixed to the rotating platform. Several directions of launching the steel ball can be shown then (see {numref}`Figure {number} <1e2002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e2002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e2002/figure_1.png
----
.
```
But no matter what the direction of launching will be, the curvature of the clockwise rotating board is always counterclockwise. (It will take some practice to launch the ball by hand on the rotating ramp.)
@@ -57,23 +55,21 @@ name: 1e2002/figure_1.png
## Explanation
1. Take a transparent sheet and place this on an overhead projector. One demonstrator draws a straight line on the sheet across the ohp, while the other demonstrator turns the sheet round in a clockwise direction. It clearly can be seen that on the sheet, a counterclockwise curving path is drawn.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1e2002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1e2002_figure_2.png
+
.
```
- We also show prepared overhead sheets to elucidate the curvature more exactly. (See {numref}`Figure {number} <1e2002/figure_2.png>` A, B and C. {numref}`Figure {number} <1e2002/figure_2.png>`C shows how the path on the rotating sheet/platform can be constructed: On sheet {numref}` {number} <1e2002/figure_2.png>`A the "ball" moves with a constant speed; on sheet {numref}`{number} <1e2002/figure_2.png>`C there is a rotation of $10^{\circ}$ for every $2 \mathrm{~cm}$ displacement on {numref}` {number} <1e2002/figure_2.png>`A). Also, on these sheets, the counterclockwise curvature is clear.
+ We also show prepared overhead sheets to elucidate the curvature more exactly. (See {numref}`Figure {number} <1e2002_figure_2.png>` A, B and C. {numref}`Figure {number} <1e2002_figure_2.png>`C shows how the path on the rotating sheet/platform can be constructed: On sheet {numref}` {number} <1e2002_figure_2.png>`A the "ball" moves with a constant speed; on sheet {numref}`{number} <1e2002_figure_2.png>`C there is a rotation of $10^{\circ}$ for every $2 \mathrm{~cm}$ displacement on {numref}` {number} <1e2002_figure_2.png>`A). Also, on these sheets, the counterclockwise curvature is clear.
+
+2. $\vec{F}_{\text {cor }}=2 m\left(\vec{v}^{'} \times \vec{\omega}\right)$. $\vec{v}^{'}$ and $\vec{\omega}$ are continuously perpendicular to each other. {numref}`Figure {number} <1e2002_figure_3.png>` shows the direction of the resulting $F_{\text {cor }}$. So $F_{c o r}$ points as seen from $\bar{v}^{'}$ continuously to the left, giving $m$ a counterclockwise path.
-2. $\vec{F}_{\text {cor }}=2 m\left(\vec{v}^{'} \times \vec{\omega}\right)$. $\vec{v}^{'}$ and $\vec{\omega}$ are continuously perpendicular to each other. {numref}`Figure {number} <1e2002/figure_3.png>` shows the direction of the resulting $F_{\text {cor }}$. So $F_{c o r}$ points as seen from $\bar{v}^{'}$ continuously to the left, giving $m$ a counterclockwise path.
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1e2002_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1e2002/figure_3.png
----
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2003 Coriolis/1E2003.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2003 Coriolis/1E2003.md
index fa7c4320..6d885017 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2003 Coriolis/1E2003.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2003 Coriolis/1E2003.md
@@ -8,11 +8,10 @@ To show the effect on an object moving with constant velocity in a rotating refe
* 1E30 (Coriolis Effect)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2003_figure_0.png
+
.
```
@@ -30,17 +29,8 @@ name: 1e2003/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/8Qdkv0y7fFw?si=vVCM4Kh5RulQ7HD4
+```
This demonstration is equal to [Coriolis](../1E2002%20Coriolis/1E2002.md). The difference is that now the camera presents directly to the audience what is observed on the rotating platform.
@@ -49,13 +39,12 @@ Again, show that the steel ball follows a straight line in the lecture hall's fr
Rotate the platform in both directions.
## Explanation
-$\vec{F}_{\text {cor }}=2 m\left(\bar{v}^{'} \times \bar{\omega}\right) . \vec{v}^{'}$ and $\bar{\omega}$ are continuously perpendicular to each other. {numref}`Figure {number} <1e2003/figure_1.png>` shows the direction of the resulting $F_{\text {cor }}$. So $F_{\text {cor }}$ points as seen from $\vec{v}^{'}$ continuously to the left, giving $m$ a counter clockwise path.
+$\vec{F}_{\text {cor }}=2 m\left(\bar{v}^{'} \times \bar{\omega}\right) . \vec{v}^{'}$ and $\bar{\omega}$ are continuously perpendicular to each other. {numref}`Figure {number} <1e2003_figure_1.png>` shows the direction of the resulting $F_{\text {cor }}$. So $F_{\text {cor }}$ points as seen from $\vec{v}^{'}$ continuously to the left, giving $m$ a counter clockwise path.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e2003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e2003/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2004 Coriolis Merry go Round/1E2004.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2004 Coriolis Merry go Round/1E2004.md
index 9b76a0f8..3efedd52 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2004 Coriolis Merry go Round/1E2004.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2004 Coriolis Merry go Round/1E2004.md
@@ -9,11 +9,10 @@ To have students experience forces (centrifugal and Coriolis) in a rotating fram
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2004_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2005 Coriolis/1E2005.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2005 Coriolis/1E2005.md
index 051562c7..f60fcd51 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2005 Coriolis/1E2005.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2005 Coriolis/1E2005.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2005_figure_0.png
+
.
```
@@ -28,13 +27,12 @@ name: 1e2005/figure_0.png
## Presentation
On the globe, our local position is indicated by sticking a small puppet at our coordinates (Delft, $52^{\circ}$ northern latitude; see Diagram A). On the globe, the sense of rotation is indicated by arrows stuck to the equator. This sense of rotation is also marked by the $\omega_{0}$-vector stuck into the North Pole.
-The flexible straw is used as a resource to indicate simultaneously the direction of $\omega_{0}$ and the direction in which an object is moving (velocity $v$ ). The long arm of the straw is used to indicate the direction of $\omega_{0}$, and the short arm is used to indicate the direction of $v$. Applying the corkscrew rule ( $\vec{F}_{\text {cor }}=-2 m(\vec{\omega} \times \vec{v})$ ), the direction of $F_{\text {cor }}$ is indicated by sticking the toothpick into the elbow of the flexible straw (see Diagram). The advantage of using the flexible straw is that easily the angle between $\omega_{o}$ and $v$ can be changed; the toothpick can be easily shifted in and out the elbow when the corkscrew rule indicates that the direction of $F_{\text {cor }}$ is different (see {numref}`Figure {number} <1e2005/figure_1.png>`).
+The flexible straw is used as a resource to indicate simultaneously the direction of $\omega_{0}$ and the direction in which an object is moving (velocity $v$ ). The long arm of the straw is used to indicate the direction of $\omega_{0}$, and the short arm is used to indicate the direction of $v$. Applying the corkscrew rule ( $\vec{F}_{\text {cor }}=-2 m(\vec{\omega} \times \vec{v})$ ), the direction of $F_{\text {cor }}$ is indicated by sticking the toothpick into the elbow of the flexible straw (see Diagram). The advantage of using the flexible straw is that easily the angle between $\omega_{o}$ and $v$ can be changed; the toothpick can be easily shifted in and out the elbow when the corkscrew rule indicates that the direction of $F_{\text {cor }}$ is different (see {numref}`Figure {number} <1e2005_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1e2005_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1e2005/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/1E2006.md b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/1E2006.md
index be2631ae..85826fe2 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/1E2006.md
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/1E2006.md
@@ -8,11 +8,10 @@ To show that the surface of a rotating liquid forms a paraboloid
* 2B20 (Static Pressure)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1e2006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1e2006_figure_0.png
+
.
```
@@ -22,37 +21,34 @@ name: 1e2006/figure_0.png
* Black screen
## Presentation
- The glass beaker is half-filled with water and submerged in a square reservoir. Using an electric motor, the beaker is set to rotate. Gradually, the liquid climbs the wall of the beaker until it stabilises. The resulting paraboloid shape becomes visible. A video camera and projector are used to project the image of the paraboloid onto the blackboard. Using chalk, the shape of the parabola is traced on the board. Next, it is checked whether the drawn shape is truly a paraboloid by identifying the focal point ($F$) and course line ($c$). Our experience is that the positions of this point and line are found quickly by trial and error (until the distances of focal point and course line to the drawn line are equal: see {numref}`Figure {number} <1E2006/figure_1>`).
+ The glass beaker is half-filled with water and submerged in a square reservoir. Using an electric motor, the beaker is set to rotate. Gradually, the liquid climbs the wall of the beaker until it stabilises. The resulting paraboloid shape becomes visible. A video camera and projector are used to project the image of the paraboloid onto the blackboard. Using chalk, the shape of the parabola is traced on the board. Next, it is checked whether the drawn shape is truly a paraboloid by identifying the focal point ($F$) and course line ($c$). Our experience is that the positions of this point and line are found quickly by trial and error (until the distances of focal point and course line to the drawn line are equal: see {numref}`Figure {number} <1E2006_figure_1>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1E2006_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1E2006/figure_1
----
.
```
## Explanation
-1. In a rotating reference frame, the liquid is in static equilibrium. In this reference frame, the sum of the forces acting on the particles on the surface will be perpendicular to that surface. Two forces are acting on such a particle: gravity, $F_{1}=d m g$, and the centrifugal force, $F_{2}=d m \omega^{2} r$. {numref}`Figure {number} <1E2006/figure_2>` shows: $\tan \alpha=\frac{d y}{d x}=\frac{\omega^{2} x}{g}$ and from this $y=\frac{1}{2} \frac{\omega^{2} x^{2}}{g}+c$. This is the formula of a parabola.
+1. In a rotating reference frame, the liquid is in static equilibrium. In this reference frame, the sum of the forces acting on the particles on the surface will be perpendicular to that surface. Two forces are acting on such a particle: gravity, $F_{1}=d m g$, and the centrifugal force, $F_{2}=d m \omega^{2} r$. {numref}`Figure {number} <1E2006_figure_2>` shows: $\tan \alpha=\frac{d y}{d x}=\frac{\omega^{2} x}{g}$ and from this $y=\frac{1}{2} \frac{\omega^{2} x^{2}}{g}+c$. This is the formula of a parabola.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1E2006_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1E2006/figure_2
----
.
```
-The constant $c$ indicates the position of the lowest point of the rotating liquid. If the $x$ axis in {numref}`Figure {number} <1E2006/figure_1>` is located in the surface of the liquid at $\omega=0$, then, because of the conservation of mass and the assumed incompressibility of the water, one obtains:
+The constant $c$ indicates the position of the lowest point of the rotating liquid. If the $x$ axis in {numref}`Figure {number} <1E2006_figure_1>` is located in the surface of the liquid at $\omega=0$, then, because of the conservation of mass and the assumed incompressibility of the water, one obtains:
$\int_{0}^{a} y d x=0$ After integration we find: $c=-\frac{1}{6} \frac{\omega^{2} a^{2}}{g}$
-2. Explaining can also be done from the point of view of hydrostatics (see {numref}`Figure {number} <1E2006/figure_3>`).
+2. Explaining can also be done from the point of view of hydrostatics (see {numref}`Figure {number} <1E2006_figure_3>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1E2006_figure_3
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1E2006/figure_3
----
.
```
diff --git a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/figures/source_figure_2.svg b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/figures/source_figure_2.svg
index be60a9e8..7ad0fbdf 100644
--- a/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/figures/source_figure_2.svg
+++ b/book/book/1 mechanics/1E relative motion/1E20 Rot Ref/1E2006 Rotating Liquid/figures/source_figure_2.svg
@@ -49,7 +49,7 @@
inkscape:isstock="true"
inkscape:collect="always"
preserveAspectRatio="xMidYMid">
diff --git a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/1F2001.md b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/1F2001.md
index 0f6b6b9a..321df7ed 100644
--- a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/1F2001.md
+++ b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/1F2001.md
@@ -9,11 +9,10 @@ To show an example of Newton's first law
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1f2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1f2001_figure_0.png
+
.
```
@@ -24,17 +23,8 @@ name: 1f2001/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/BSclXCB8nKc?si=tr-6ImnEZfDLtoIo
+```
Set the table as shown in Diagram (light a candle etc.). Our tablecloth is technically not a tablecloth. We use a sheet of paper (see Diagram). Take the protruding free end of the paper in both hands and give a sharp downward jerk. The sheet of paper comes out from under the glasses and they are hardly moved. (Even the water in the glasses is not disturbed!)
@@ -55,7 +45,6 @@ $d=\frac{1}{2} k_{1} g \Delta t^{2}\left(1+\frac{k_{1}}{k_{2}}\right)$, where $k
```{iframe} https://www.youtube.com/watch?v=jaxgBPQ2STk
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_BSclXCB8nKc_si_tr_6ImnEZfDLtoIo_.svg b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_BSclXCB8nKc_si_tr_6ImnEZfDLtoIo_.svg
new file mode 100644
index 00000000..31de9ebb
--- /dev/null
+++ b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_BSclXCB8nKc_si_tr_6ImnEZfDLtoIo_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_watch_v_jaxgBPQ2STk.svg b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_watch_v_jaxgBPQ2STk.svg
new file mode 100644
index 00000000..151f6675
--- /dev/null
+++ b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2001 Tablecloth Pull/qr_images/qrcode_watch_v_jaxgBPQ2STk.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2002 Newtons Hammer/1F2002.md b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2002 Newtons Hammer/1F2002.md
index cc72ef79..7d243405 100644
--- a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2002 Newtons Hammer/1F2002.md
+++ b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2002 Newtons Hammer/1F2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1f2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1f2002_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2003 Not Breaking a Wineglass/1F2003.md b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2003 Not Breaking a Wineglass/1F2003.md
index 88079f6e..84794333 100644
--- a/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2003 Not Breaking a Wineglass/1F2003.md
+++ b/book/book/1 mechanics/1F newton 1/1F20 Inertia of Rest/1F2003 Not Breaking a Wineglass/1F2003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1f2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1f2003_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3001 Galileos Thoughts/1F3001.md b/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3001 Galileos Thoughts/1F3001.md
index 94f5b7e3..eda6fb4d 100644
--- a/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3001 Galileos Thoughts/1F3001.md
+++ b/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3001 Galileos Thoughts/1F3001.md
@@ -8,11 +8,10 @@ To show the thought experiment of Galileo Galilei on the inertia of movement.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1f3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1f3001_figure_0.png
+
.
```
@@ -27,15 +26,14 @@ The right-hand side of the gutter is placed at a steep angle. The ball is releas
The right-hand support of the gutter is placed in its most right position. Now the released ball travels the whole gutter.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1f3001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1f3001_figure_1.png
+
.
```
-The right-hand side support is removed, and this part of the gutter now lies horizontally on the table. Ask the students how far the ball will travel now when released as before: "What is its final position?" (see {numref}`Figure {number} <1f3001/figure_1.png>`). After receiving their answers, the ball can be released (In our setup, the ball disappears in a sink).
+The right-hand side support is removed, and this part of the gutter now lies horizontally on the table. Ask the students how far the ball will travel now when released as before: "What is its final position?" (see {numref}`Figure {number} <1f3001_figure_1.png>`). After receiving their answers, the ball can be released (In our setup, the ball disappears in a sink).
## Explanation
Galilei reasoned that when the right-hand part of the gutter is aligned horizontally, the ball can never reach the same height again. So, it will keep rolling to the right perpetually; the ball is moving and will remain in motion! This is what we have now dubbed Newton's first law.
diff --git a/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3002 Walk and Ball/1F3002.md b/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3002 Walk and Ball/1F3002.md
index d411fec5..0bc27f5f 100644
--- a/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3002 Walk and Ball/1F3002.md
+++ b/book/book/1 mechanics/1F newton 1/1F30 Inertia of Motion/1F3002 Walk and Ball/1F3002.md
@@ -9,11 +9,10 @@ To demonstrate that vertical and horizontal motions are independent of each othe
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1f3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1f3002_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/1G1001.md b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/1G1001.md
index 3b37d72d..441c4b5a 100644
--- a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/1G1001.md
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/1G1001.md
@@ -3,27 +3,17 @@
## Aim
To show that the force on an object is low as long as the acceleration/deceleration is low.
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/tT_4qx6vL-U?si=mAmqaIo4XJbwLwF2
+```
## Subjects
* 1G10 (Force, Mass, and Acceleration)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1g1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1g1001_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/qr_images/qrcode_tT_4qx6vL_U_si_mAmqaIo4XJbwLwF2_.svg b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/qr_images/qrcode_tT_4qx6vL_U_si_mAmqaIo4XJbwLwF2_.svg
new file mode 100644
index 00000000..99035ba2
--- /dev/null
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1001 Throwing Eggs/qr_images/qrcode_tT_4qx6vL_U_si_mAmqaIo4XJbwLwF2_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1002 Bungee Jumper/1G1002.md b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1002 Bungee Jumper/1G1002.md
index 89fbad38..42cc101f 100644
--- a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1002 Bungee Jumper/1G1002.md
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1002 Bungee Jumper/1G1002.md
@@ -8,11 +8,10 @@ To show that a bungee jumper falls with an acceleration greater than $g$.
* 1D40 (Motion of the center of mass)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1g1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1g1002_figure_0.png
+
.
```
@@ -32,24 +31,22 @@ name: 1g1002/figure_0.png
## Presentation
The ladder is set up, and the chain with the yellow block is attached to it. It hangs from such a height that the yellow block just touches the ground when the chain is fully extended (see Diagram A, where the end with the yellow block is temporarily fixed to the ladder).
-- Firstly, two small blocks of wood are kept fixed, squeezed between your thumb and forefinger. When you let them go, they fall together towards the ground and touch it at the same time (see Diagram B and {numref}`Figure {number} <1g1002/figure_1.png>`).
+- Firstly, two small blocks of wood are kept fixed, squeezed between your thumb and forefinger. When you let them go, they fall together towards the ground and touch it at the same time (see Diagram B and {numref}`Figure {number} <1g1002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1g1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1g1002/figure_1.png
----
.
```
-- The red and yellow blocks, which are attached to the chain, are held between your fingers (see Diagram C). Then, release them (see Diagram D) and observe that the yellow block touches the ground before the freely falling red block does. The difference in displacement can already be seen during the fall (see {numref}Figure {number} <1g1002/figure_2.png>), but it becomes especially clear at touchdown, when two distinct bumps are heard.
+- The red and yellow blocks, which are attached to the chain, are held between your fingers (see Diagram C). Then, release them (see Diagram D) and observe that the yellow block touches the ground before the freely falling red block does. The difference in displacement can already be seen during the fall (see {numref}Figure {number} <1g1002_figure_2.png>), but it becomes especially clear at touchdown, when two distinct bumps are heard.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1g1002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1g1002_figure_2.png
+
.
```
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/1G1003.md b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/1G1003.md
index 8f75fadd..bde1a877 100644
--- a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/1G1003.md
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/1G1003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1g1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1g1003_figure_0.png
+
.
```
@@ -31,45 +30,34 @@ name: 1g1003/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/FBIW7GdcKgU?si=4jik0LCy74sTY5LB
+```
1. The mass of $5 \mathrm{~kg}$ is suspended by a strong thread. Through a thin cotton thread, it can be displaced horizontally by slowly pulling on this thread. However, when a quick jerk is given, the thin cotton thread breaks.
2. Using a thin thread, the two masses of $1 \mathrm{~kg}$ are hung on to the bar. On the bottom side of each mass, a free-hanging thread is tied. Ask the students which thread will break, the upper or the lower, when we slowly increase the pulling force on the bottom thread. Slowly pull the lower thread of one mass. This will cause the upper thread to break. Then ask the students which thread will break when we increase the pulling force on the lower thread very fast. Pull the lower thread on the second mass rapidly. This time, the lower thread will break.
## Explanation
-1. The tension ( $T$ ) in the thin thread equals the force applied to the thread: $F=T$. This force accelerates $m$ (see {numref}`Figure {number} <1g1003/figure_1.png>`). A jerk means that $a$ is high; a high $F(=m a)$ is needed for that. The tension in the thread will be high, resulting in the breaking of this thread.
+1. The tension ( $T$ ) in the thin thread equals the force applied to the thread: $F=T$. This force accelerates $m$ (see {numref}`Figure {number} <1g1003_figure_1.png>`). A jerk means that $a$ is high; a high $F(=m a)$ is needed for that. The tension in the thread will be high, resulting in the breaking of this thread.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1g1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1g1003/figure_1.png
----
.
```
2.
*a. A general explanation* When we increase the pulling force slowly, a low acceleration $a$ is imparted to the mass. The mass can follow this acceleration, causing a stretch in the upper thread. The upper thread also supports the weight of the mass, so it is the thread that eventually breaks. However, when we try to give the mass a high acceleration suddenly, the inertia of the mass prevents it from following the motion of our hand quickly; it lags. As a result, the thread between our hand and the mass experiences a large stretch and breaks. Meanwhile, the upper thread remains unaffected because the mass is no longer moving downwards; it only supports the weight of the mass, as it did before.
- *b. An analytical explanation* Using Newton's second law gives still more insight. The forces acting on $m$ are $T_{1}, T_{2}$ and $m g$ (see {numref}`Figure {number} <1g1003/figure_2.png>`). $T_{1}$ is the tension in the upper thread. The tension in the lower thread is $T_{2}$. The acceleration $a$ that $m$ obtains can be determined by: $m a=T_{2}+m g-T_{1}$
+ *b. An analytical explanation* Using Newton's second law gives still more insight. The forces acting on $m$ are $T_{1}, T_{2}$ and $m g$ (see {numref}`Figure {number} <1g1003_figure_2.png>`). $T_{1}$ is the tension in the upper thread. The tension in the lower thread is $T_{2}$. The acceleration $a$ that $m$ obtains can be determined by: $m a=T_{2}+m g-T_{1}$
It follows: $m a-m g=T_{2}-T_{1}$ or $m(a-g)=T_{2}-T_{1}$
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1g1003/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1g1003_figure_2.png
+
.
```
@@ -89,7 +77,6 @@ This last explanation shows the power of Newton's second law: now it is possible
```{iframe} https://www.youtube.com/watch?v=dNgJuHJAmnA
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_FBIW7GdcKgU_si_4jik0LCy74sTY5LB_.svg b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_FBIW7GdcKgU_si_4jik0LCy74sTY5LB_.svg
new file mode 100644
index 00000000..f37ab575
--- /dev/null
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_FBIW7GdcKgU_si_4jik0LCy74sTY5LB_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_watch_v_dNgJuHJAmnA.svg b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_watch_v_dNgJuHJAmnA.svg
new file mode 100644
index 00000000..f728ac08
--- /dev/null
+++ b/book/book/1 mechanics/1G newton 2/1G10 Fma/1G1003 Pulling a Thread/qr_images/qrcode_watch_v_dNgJuHJAmnA.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1001 Who is the Strongest in a Collision/1H1001.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1001 Who is the Strongest in a Collision/1H1001.md
index de0a6766..b49202d0 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1001 Who is the Strongest in a Collision/1H1001.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1001 Who is the Strongest in a Collision/1H1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1001_figure_0.png
+
.
```
@@ -27,24 +26,23 @@ name: 1h1001/figure_0.png
## Presentation
-Presentation: The force sensors are attached to each cart and connected to the interface (see Diagram). The software is prepared to read and graphically display both forces $(-1$ to $+12 \mathrm{~N})$ during about $10 \mathrm{~s}$. Both carts are positioned on the track at about $5 \mathrm{~m}$ away from each other. The data recording is started, and both carts are pushed towards each other manually. The recording is stopped after a collision occurs. Students can now observerve the registered force data (see {numref}`Figure {number} <1h1001/figure_1.png>` left).
+Presentation: The force sensors are attached to each cart and connected to the interface (see Diagram). The software is prepared to read and graphically display both forces $(-1$ to $+12 \mathrm{~N})$ during about $10 \mathrm{~s}$. Both carts are positioned on the track at about $5 \mathrm{~m}$ away from each other. The data recording is started, and both carts are pushed towards each other manually. The recording is stopped after a collision occurs. Students can now observerve the registered force data (see {numref}`Figure {number} <1h1001_figure_1.png>` left).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1h1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1h1001/figure_1.png
----
.
```
-The part of the data that resembles the collision is magnified (see {numref}`Figure {number} <1h1001/figure_1.png>` right). It can be seen that at any moment, the force on both carts is the same. $1 \mathrm{~kg}$ is added to one of the carts. The demonstration is repeated, again showing that the forces registered during the collision are the same at all times both carts!
+The part of the data that resembles the collision is magnified (see {numref}`Figure {number} <1h1001_figure_1.png>` right). It can be seen that at any moment, the force on both carts is the same. $1 \mathrm{~kg}$ is added to one of the carts. The demonstration is repeated, again showing that the forces registered during the collision are the same at all times both carts!
## Explanation
Newton's third law states $\vec{F}_{A \rightarrow B}=-\vec{F}_{B \rightarrow A}$, which is supported by the results of these demonstrations.
## Remarks
- The speed you give the carts by hand is, of course, not important. But when students doubt, redo a run with one cart standing still or moving at a different speed in the same direction. The data-registration will always show $\vec{F}_{A \rightarrow B}=-\vec{F}_{B \rightarrow A}$.
-- In the right graph of {numref}`Figure {number} <1h1001/figure_1.png>` can be seen which cart has the spring mounted to its force sensor: A damped vibration is seen after the collision. The force sensor itself also vibrates after the collision, as shown in the graph of the other force sensor.
+- In the right graph of {numref}`Figure {number} <1h1001_figure_1.png>` can be seen which cart has the spring mounted to its force sensor: A damped vibration is seen after the collision. The force sensor itself also vibrates after the collision, as shown in the graph of the other force sensor.
## Sources
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1002 Who is Pulling/1H1002.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1002 Who is Pulling/1H1002.md
index 4d0f8338..82b36993 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1002 Who is Pulling/1H1002.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1002 Who is Pulling/1H1002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1002_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1003 Trying Hard to Pull Differently/1H1003.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1003 Trying Hard to Pull Differently/1H1003.md
index 6ca1fbe7..0a89405c 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1003 Trying Hard to Pull Differently/1H1003.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1003 Trying Hard to Pull Differently/1H1003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1003_figure_0.png
+
.
```
@@ -28,13 +27,12 @@ name: 1h1003/figure_0.png
## Presentation
On the monitor, two graphs are presented for each force sensor. The software is set in such a way that one of the sensors presents $-F$.
-Two demonstrators take each of the sensors. They start both pulling randomly. The display shows clearly that whatever they do, both force sensors measure the same force: $-F$ and $-F$ (see {numref}`Figure {number} <1h1003/figure_1.png>`).
+Two demonstrators take each of the sensors. They start both pulling randomly. The display shows clearly that whatever they do, both force sensors measure the same force: $-F$ and $-F$ (see {numref}`Figure {number} <1h1003_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1h1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1h1003/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
index e5d35804..f134986a 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
@@ -14,11 +14,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1004_figure_0.png
+
.
```
@@ -56,7 +55,6 @@ The mechanism of movement can also be explained by Newton's third law. The cart
```{iframe} https://www.youtube.com/watch?v=mww2JDELZyE
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/qr_images/qrcode_watch_v_mww2JDELZyE.svg b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/qr_images/qrcode_watch_v_mww2JDELZyE.svg
new file mode 100644
index 00000000..7e76354a
--- /dev/null
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/qr_images/qrcode_watch_v_mww2JDELZyE.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1005 Magnet Symmetry/1H1005.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1005 Magnet Symmetry/1H1005.md
index 8f3fe9d6..22ee0256 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1005 Magnet Symmetry/1H1005.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1005 Magnet Symmetry/1H1005.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1005_figure_0.png
+
.
```
@@ -35,13 +34,12 @@ name: 1h1005/figure_0.png
## Remarks
-* Releasing the two magnets needs some practice (see {numref}`Figure {number} <1h1005/figure_1.png>`); both fingers need to move away from the magnets simultaneously.
+* Releasing the two magnets needs some practice (see {numref}`Figure {number} <1h1005_figure_1.png>`); both fingers need to move away from the magnets simultaneously.
+
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1h1005_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1h1005/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1006 Recoil of a Water Jet/1H1006.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1006 Recoil of a Water Jet/1H1006.md
index d7f4b795..d2b0ee6f 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1006 Recoil of a Water Jet/1H1006.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1006 Recoil of a Water Jet/1H1006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1006_figure_0.png
+
.
```
@@ -27,11 +26,10 @@ name: 1h1006/figure_0.png
## Presentation
The rubber hose with a T-junction hangs vertically down. Opening the faucet makes the end of the hose move away.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1h1006/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1h1006_figure_1.png
+
.
```
When a plate is held in the water-jet, nothing changes.
@@ -43,13 +41,12 @@ When the plate is fixed to the end of one side of the T-junction, the hose stays
To convert a downward water flow into a sideways water flow, the T-junction has to exert a force on the water. The reaction to this force is responsible for the recoil to the other side. When a plate is placed in the outgoing water stream, it also exerts a force on the plate. When this plate is fixed to the T-junction, these two forces cancel, so there is no recoil
## Remarks
-This demonstration can be performed by the students themselves, by giving each of them a flexible soda straw, giving it a $90^{\circ}$ bend ({numref}`Figure {number} <1h1006/figure_2.png>`).
+This demonstration can be performed by the students themselves, by giving each of them a flexible soda straw, giving it a $90^{\circ}$ bend ({numref}`Figure {number} <1h1006_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1h1006_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1h1006/figure_2.png
----
.
```
diff --git a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1007 Strong Magnet Weak Paperclip/1H1007.md b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1007 Strong Magnet Weak Paperclip/1H1007.md
index 7e96c523..22fbe1a8 100644
--- a/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1007 Strong Magnet Weak Paperclip/1H1007.md
+++ b/book/book/1 mechanics/1H newton 3/1H10 Act and React/1H1007 Strong Magnet Weak Paperclip/1H1007.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1h1007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1h1007_figure_0.png
+
.
```
@@ -27,13 +26,12 @@ name: 1h1007/figure_0.png
## Presentation
-The demonstration is presented as a tug-of-war between a heavy, strong horseshoe magnet and a light paperclip. After demonstrating the strength of our magnet, the setup is as shown in the Diagram. Using a camera, the magnet and paperclip are presented in more detail on a large monitor screen. The graphs, still blank, are projected using a projector (see {numref}`Figure {number} <1h1007/figure_1.png>`).
+The demonstration is presented as a tug-of-war between a heavy, strong horseshoe magnet and a light paperclip. After demonstrating the strength of our magnet, the setup is as shown in the Diagram. Using a camera, the magnet and paperclip are presented in more detail on a large monitor screen. The graphs, still blank, are projected using a projector (see {numref}`Figure {number} <1h1007_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1h1007_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1h1007/figure_1.png
----
.
```
@@ -41,7 +39,7 @@ First, the force sensors are set to zero. Students see this in the projected gra
Then, the data is collected as a recording and is acquired by sliding the lower force sensor upward along the aluminium bars. The paperclip is brought closer to the magnet until it touches one of the poles. Afterward, the lower force sensor is lowered again (detaching the paperclip from the magnet pole) to its point of origin. The data collection is stopped.
-The recorded data are discussed now; a region of interest can be selected (see {numref}`Figure {number} <1h1007/figure_1.png>`). It can be observed that the force-time relationship is a complicated one; nevertheless, Newton's third law is valid: at every moment in time, we see $F_{\text {paperclip }}=-F_{\text {magnet }}$.
+The recorded data are discussed now; a region of interest can be selected (see {numref}`Figure {number} <1h1007_figure_1.png>`). It can be observed that the force-time relationship is a complicated one; nevertheless, Newton's third law is valid: at every moment in time, we see $F_{\text {paperclip }}=-F_{\text {magnet }}$.
## Explanation
There is no explanation here, since Newton's laws are just a set of hypotheses which appear to agree with our everyday experience. Our demonstration is another experiment demonstrating the validity of the third law.
diff --git a/book/book/1 mechanics/1J rigid bodies/1J20 Equilibrium/1J2001 Equilibrium and Potential Energy/1J2001.md b/book/book/1 mechanics/1J rigid bodies/1J20 Equilibrium/1J2001 Equilibrium and Potential Energy/1J2001.md
index 0d74e379..687cce31 100644
--- a/book/book/1 mechanics/1J rigid bodies/1J20 Equilibrium/1J2001 Equilibrium and Potential Energy/1J2001.md
+++ b/book/book/1 mechanics/1J rigid bodies/1J20 Equilibrium/1J2001 Equilibrium and Potential Energy/1J2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1j2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1j2001_figure_0.png
+
.
```
@@ -30,13 +29,12 @@ The other Petri dish is filled with water to the rim and even a little bit more;
## Explanation
The difference between the two Petri dishes is the shape of the meniscus of the water surface. The dish that is half-filled with water has a hollow meniscus, while the other one has a spherical meniscus. The ball in the half-filled dish floats upwards when approaching the rim. This is the counterintuitive part of the demonstration. The same holds for the ball floating in the filled dish; this ball "refuses" to float downwards when approaching the downward incline.
-The key to understanding is the condition for equilibrium in a conservative force field, which reads: $d E_{p}=0$. This equilibrium is stable when $E_{p}$ (potential energy) is a minimum. Applying this to our demonstration, we have to consider not only the table tennis ball but also the water it displaces. To achieve an equilibrium, the common center of mass of these two should be positioned as low as possible, and so, the table tennis ball as high as possible. In the situation with the hollow meniscus, this is in the water at the rim. In the situation with the spherical meniscus, this is in the water away from the rim (see also {numref}`Figure {number} <1j2001/figure_1.png>`).
+The key to understanding is the condition for equilibrium in a conservative force field, which reads: $d E_{p}=0$. This equilibrium is stable when $E_{p}$ (potential energy) is a minimum. Applying this to our demonstration, we have to consider not only the table tennis ball but also the water it displaces. To achieve an equilibrium, the common center of mass of these two should be positioned as low as possible, and so, the table tennis ball as high as possible. In the situation with the hollow meniscus, this is in the water at the rim. In the situation with the spherical meniscus, this is in the water away from the rim (see also {numref}`Figure {number} <1j2001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1j2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1j2001/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1J rigid bodies/1J30 Resolution of Forces/1J3001 Strong Professor/1J3001.md b/book/book/1 mechanics/1J rigid bodies/1J30 Resolution of Forces/1J3001 Strong Professor/1J3001.md
index 938d7ec2..96c9d27d 100644
--- a/book/book/1 mechanics/1J rigid bodies/1J30 Resolution of Forces/1J3001 Strong Professor/1J3001.md
+++ b/book/book/1 mechanics/1J rigid bodies/1J30 Resolution of Forces/1J3001 Strong Professor/1J3001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1j3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1j3001_figure_0.png
+
.
```
@@ -23,31 +22,29 @@ name: 1j3001/figure_0.png
## Presentation
-1. The two students pull with force on the ends of the rope, keeping it in equilibrium. From above, the professor pushes downwards,in the middle of the rope, easily touching the ground, with almost no effort, while the students work extremely hard to prevent this. Both strong students give way to the weak professor. (see {numref}`Figure {number} <1j3001/figure_1.png>`)
+1. The two students pull with force on the ends of the rope, keeping it in equilibrium. From above, the professor pushes downwards,in the middle of the rope, easily touching the ground, with almost no effort, while the students work extremely hard to prevent this. Both strong students give way to the weak professor. (see {numref}`Figure {number} <1j3001_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1j3001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1j3001/figure_1.png
----
.
```
2. A thick nylon thread is shown and it is clear to all that by hand it cannot be broken. (The strong students can try it.) The thread is fitted between the extremities of the hinged bars (see Diagram). The professor pushes vertically downward on the joint between the bars and breaks the thread.
-3. A piece of rope, that cannot be broken by hand, is tightly knotted around the top of a table (see {numref}`Figure {number} <1j3001/figure_2.png>`B). A metal bar is stuck under it and when the bar is pulled upwards, the rope breaks easily.
+3. A piece of rope, that cannot be broken by hand, is tightly knotted around the top of a table (see {numref}`Figure {number} <1j3001_figure_2.png>`B). A metal bar is stuck under it and when the bar is pulled upwards, the rope breaks easily.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1j3001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1j3001/figure_2.png
----
.
```
## Explanation
We consider the situations as being in equilibrium.
-1. Equilibrium requires that there is resolution of force (see {numref}`Figure {number} <1j3001/figure_1.png>`). The students need a large force to cancel the small force of the professor.
-2. In equilibrium the force downward should be in the direction of the bars ( $F_{1}$ and $F_{2}$ in {numref}`Figure {number} <1j3001/figure_2.png>`). The horizontal components of these forces give the tension $T$ in the thread. $F_{1}$ and $F_{2}$ are the components of force along the bars of the professor's force $P$. The more the bars are pressed downward, the higher the components $F_{1}$ and $F_{2}$ will be and the higher the tension $T$ in the thread.
+1. Equilibrium requires that there is resolution of force (see {numref}`Figure {number} <1j3001_figure_1.png>`). The students need a large force to cancel the small force of the professor.
+2. In equilibrium the force downward should be in the direction of the bars ( $F_{1}$ and $F_{2}$ in {numref}`Figure {number} <1j3001_figure_2.png>`). The horizontal components of these forces give the tension $T$ in the thread. $F_{1}$ and $F_{2}$ are the components of force along the bars of the professor's force $P$. The more the bars are pressed downward, the higher the components $F_{1}$ and $F_{2}$ will be and the higher the tension $T$ in the thread.
3. The tension in the string due to the upward force is much higher than this upward force (construct the force-balance diagram to see this).
## Remarks
diff --git a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1001 Pulling a Spool/1K1001.md b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1001 Pulling a Spool/1K1001.md
index 1cf02d31..68cf22be 100644
--- a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1001 Pulling a Spool/1K1001.md
+++ b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1001 Pulling a Spool/1K1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k1001_figure_0.png
+
.
```
@@ -24,17 +23,8 @@ name: 1k1001/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/2lsnQpFVnKQ?si=0lnTm9o0Aaor1f_c
+```
Show the simple construction of spool and wound thread to the students. The demonstrator takes the end of the thread in his hands and wants to pull in a horizontal direction. Ask the students in which direction the spool will roll. After their answers, pull .... and the spool will roll into the same direction as the demonstrator pulls.
@@ -43,34 +33,31 @@ The thread is wound to the spool again. The demonstrator takes the end of the th
These two demonstrations induce the idea that it should be possible to pull in such a direction that the spool will not roll at all! Ask the students in which direction you need to pull the thread to get this situation. After their answers, experimentally search the right angle: the spool skids.
## Explanation
-The direction in which the spool rolls is determined by the direction of the torque on the spool about the contact point. The critical angle is defined by extending the line of the pulled thread so that this line passes through the point of contact between the spool and the table. A force directed along this line produces zero torque on the spool about the contact point. (see {numref}`Figure {number} <1k1001/figure_1.png>`)
+The direction in which the spool rolls is determined by the direction of the torque on the spool about the contact point. The critical angle is defined by extending the line of the pulled thread so that this line passes through the point of contact between the spool and the table. A force directed along this line produces zero torque on the spool about the contact point. (see {numref}`Figure {number} <1k1001_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 40%
+:label: 1k1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 40%
-name: 1k1001/figure_1.png
----
.
```
## Remarks
-- When pulling at very shallow angles, the spool orientation is not stable unless the thread comes off the spool at its center. This can be prevented by using a ribbon rather than a thread or using a large spool that is made in such a way that the thread can only be rolled in the centre of the spool ({numref}`Figure {number} <1k1001/figure_2.png>`).
+- When pulling at very shallow angles, the spool orientation is not stable unless the thread comes off the spool at its center. This can be prevented by using a ribbon rather than a thread or using a large spool that is made in such a way that the thread can only be rolled in the centre of the spool ({numref}`Figure {number} <1k1001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k1001/figure_2.png
----
.
```
-- A nice extension of this demonstration is to set the system up so that the string passes over a pulley and the force is supplied by hanging a weight from the end of the string ({numref}`Figure {number} <1k1001/figure_3.png>`).
+- A nice extension of this demonstration is to set the system up so that the string passes over a pulley and the force is supplied by hanging a weight from the end of the string ({numref}`Figure {number} <1k1001_figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1k1001/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1k1001_figure_3.png
+
.
```
diff --git a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1002 Boomerang Ball/1K1002.md b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1002 Boomerang Ball/1K1002.md
index 20aa115a..cb3d5ba5 100644
--- a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1002 Boomerang Ball/1K1002.md
+++ b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1002 Boomerang Ball/1K1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k1002_figure_0.png
+
.
```
@@ -33,27 +32,25 @@ name: 1k1002/figure_0.png
## Explanation
As an introduction to an explanation a basketball is rolled over the floor, hitting the wall and rolling back to you. But in this rolling back it is also bouncing up and down. Confronting your students with the question "where originates this vertical momentum?" will lead them (I hope) to the answer: "the impulse of the friction force while the ball touches the vertical wall".
- As a second introduction to an explanation the basketball is thrown as shown in {numref}`Figure {number} <1k1002/figure_1.png>`A.
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1k1002/figure_1.png
----
+ As a second introduction to an explanation the basketball is thrown as shown in {numref}`Figure {number} <1k1002_figure_1.png>`A.
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1k1002_figure_1.png
+
.
```
-(Also see the demonstration ["Throwing a basketball"](../1K1005 Throwing a Basketball/1K1005.md)). The ball is thrown without rotation, but after bouncing it rotates (the lines on the basketball make this rotation very well visible). The cause for this rotation is the torque $\vec{M}$, due to the friction force $\vec{F}_{r}:\left(\vec{M}=\vec{r} \times \vec{F}_{r}\right)$ (see {numref}`Figure {number} <1k1002/figure_1.png>`B). $\vec{F}_{r}$, that acts during a certain time $\Delta t$, also causes a decrease of the momentum ( $\left.\Delta p_{h}\right)$ in the horizontal direction of the moving ball ( $\Delta \stackrel{\rightharpoonup}{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$ ). The result is that, after hitting the floor, the ball not only rotates but also rises at a steeper angle than it had in its approach. (See {numref}`Figure {number} <1k1002/figure_1.png>`C; $p_{v}$ only reverses its direction and does not change its magnitude; suppose the bounce completely elastic). {numref}`Figure {number} <1k1002/figure_2.png>` shows the ball on hitting the bottom-side of the table-top. Observing the movement of the ball's surface with respect to the bottom-side of the tabletop makes clear that the friction force is (again) directed to the left.
+(Also see the demonstration ["Throwing a basketball"](../1K1005 Throwing a Basketball/1K1005.md)). The ball is thrown without rotation, but after bouncing it rotates (the lines on the basketball make this rotation very well visible). The cause for this rotation is the torque $\vec{M}$, due to the friction force $\vec{F}_{r}:\left(\vec{M}=\vec{r} \times \vec{F}_{r}\right)$ (see {numref}`Figure {number} <1k1002_figure_1.png>`B). $\vec{F}_{r}$, that acts during a certain time $\Delta t$, also causes a decrease of the momentum ( $\left.\Delta p_{h}\right)$ in the horizontal direction of the moving ball ( $\Delta \stackrel{\rightharpoonup}{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$ ). The result is that, after hitting the floor, the ball not only rotates but also rises at a steeper angle than it had in its approach. (See {numref}`Figure {number} <1k1002_figure_1.png>`C; $p_{v}$ only reverses its direction and does not change its magnitude; suppose the bounce completely elastic). {numref}`Figure {number} <1k1002_figure_2.png>` shows the ball on hitting the bottom-side of the table-top. Observing the movement of the ball's surface with respect to the bottom-side of the tabletop makes clear that the friction force is (again) directed to the left.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k1002/figure_2.png
----
.
```
Due to this horizontal impulse, $p_{h}$ even changes direction and bouncing from the bottom side, the ball even moves to the left. (The clockwise rotation will be slowed down, stopped or even reversed, because on hitting the bottom-side of the tabletop $\bar{M}$ is directed in the opposite direction.)
-Depending on the value of $p_{h}$ now, CD in {numref}`Figure {number} <1k1002/figure_2.png>` could be a possible line of movement. Explaining line DE (towards the pitcher) will be easy when you suppose a counterclockwise rotation in the path CD, because then the friction force on hitting the floor is directed again to the left increasing the horizontal component of the ball's velocity to the left! (see {numref}`Figure {number} <1k1002/figure_2.png>`B)
+Depending on the value of $p_{h}$ now, CD in {numref}`Figure {number} <1k1002_figure_2.png>` could be a possible line of movement. Explaining line DE (towards the pitcher) will be easy when you suppose a counterclockwise rotation in the path CD, because then the friction force on hitting the floor is directed again to the left increasing the horizontal component of the ball's velocity to the left! (see {numref}`Figure {number} <1k1002_figure_2.png>`B)
## Remarks
* In theory all balls will behave in this way. Yet a superball is needed to show this type of “boomerang-behavior”. That a superball performs so well is due in the first place to its high coefficient of friction and subsequently its high friction force on horizontal contact with the floor and table. And a high friction force can change the horizontal momentum dramatically.
diff --git a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1003 Boomerang Ball/1K1003.md b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1003 Boomerang Ball/1K1003.md
index 969d2df1..230808f8 100644
--- a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1003 Boomerang Ball/1K1003.md
+++ b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1003 Boomerang Ball/1K1003.md
@@ -9,11 +9,10 @@ The concept of impulse explains this very peculiar behavior of a bouncing ball.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k1003_figure_0.png
+
.
```
@@ -31,13 +30,12 @@ name: 1k1003/figure_0.png
The table is positioned as shown in Diagram. The ball is thrown as shown. The ball bounces to a fro.
## Explanation
-As a basis to explanation see the demonstration [Boomerang ball](../1K1002%20Boomerang%20Ball/1K1002.md). Using a large basketball thrown against the floor and then bouncing against a vertical wall, shows that after hitting the vertical wall the basketball still rotates clockwise. {numref}`Figure {number} <1k1003/figure_1.png>`A shows this.
+As a basis to explanation see the demonstration [Boomerang ball](../1K1002%20Boomerang%20Ball/1K1002.md). Using a large basketball thrown against the floor and then bouncing against a vertical wall, shows that after hitting the vertical wall the basketball still rotates clockwise. {numref}`Figure {number} <1k1003_figure_1.png>`A shows this.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k1003/figure_1.png
----
.
```
@@ -45,18 +43,17 @@ name: 1k1003/figure_1.png
$\vec{p}_{v}$ in P.)
-Having hit the vertical wall the ball climbs steep (see {numref}`Figure {number} <1k1003/figure_1.png>`A). A parabolic trajectory follows. On hitting the floor in $\mathrm{R}$, the friction force is directed to the right ({numref}`Figure {number} <1k1003/figure_1.png>`B). The impulse $\int F_{r} d t$ is large enough to make the component
+Having hit the vertical wall the ball climbs steep (see {numref}`Figure {number} <1k1003_figure_1.png>`A). A parabolic trajectory follows. On hitting the floor in $\mathrm{R}$, the friction force is directed to the right ({numref}`Figure {number} <1k1003_figure_1.png>`B). The impulse $\int F_{r} d t$ is large enough to make the component
$\vec{p}_{h}$ change direction and $\bar{M}=\vec{r} \times \vec{F}_{R}$ is inducing a counter clockwise rotation. It bounces towards $\mathrm{S}$ and again $F_{R}$ is directed to the inner side of the parabola, making the component $\vec{p}_{h}$ reverse direction and $\bar{M}=\vec{r} \times \vec{F}_{R}$ inducing clockwise rotation. And so on.
## Remarks
-- Practicing this demonstration against a real wall will learn that this part of the demonstration can also be appreciated on its own. Having the right speed and right angle, a very high climbing ball will be the result of your practicing. {numref}`Figure {number} <1k1003/figure_1.png>`A shows the explanation of this phenomenon: After bouncing at $\mathrm{Q}$, $\vec{p}_{v}$ has a very high value.
-- A nice variation to this demonstration is the "drunken student" (sorry, "drunken sailor"). To throw a ball that follows such a staggering trajectory, see {numref}`Figure {number} <1k1003/figure_2.png>`.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k1003/figure_2.png
----
+- Practicing this demonstration against a real wall will learn that this part of the demonstration can also be appreciated on its own. Having the right speed and right angle, a very high climbing ball will be the result of your practicing. {numref}`Figure {number} <1k1003_figure_1.png>`A shows the explanation of this phenomenon: After bouncing at $\mathrm{Q}$, $\vec{p}_{v}$ has a very high value.
+- A nice variation to this demonstration is the "drunken student" (sorry, "drunken sailor"). To throw a ball that follows such a staggering trajectory, see {numref}`Figure {number} <1k1003_figure_2.png>`.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k1003_figure_2.png
+
.
```
diff --git a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md
index 1d121ec6..e9e5d540 100644
--- a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md
+++ b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md
@@ -22,26 +22,24 @@ Let the stick go and it will hit the floor. The marked center is right in front
The demonstration is done once more but now the wheel cannot move since your foot blocks it. Let the stick go and observe that the stick falls with the center of mass on the left of yourself; it even jumps away from your right foot to the left!
## Explanation
-The behavior of the stick depends on the friction force between the tip and the floor on which it rests. When there is frictionless interaction the only forces acting on the pencil are its weight and the normal force, both of which are vertical. There are no horizontal forces on the stick. (See {numref}`Figure {number} <1k1004/figure_0.png>`.)
+The behavior of the stick depends on the friction force between the tip and the floor on which it rests. When there is frictionless interaction the only forces acting on the pencil are its weight and the normal force, both of which are vertical. There are no horizontal forces on the stick. (See {numref}`Figure {number} <1k1004_figure_0.png>`.)
+
+```{figure} figures/figure_0.png
+:width: 50%
+:label: 1k1004_figure_0.png
-```{figure} figures/figure_0.png
----
-width: 50%
-name: 1k1004/figure_0.png
----
.
```
The $20^{\circ}$ inclination is to skip the region where the wheel has too much friction to roll. In the first $20^{\circ}$ the stick receives so much impulse from friction of the wheel that the centre of mass moves.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k1004/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k1004_figure_1.png
+
.
```
-When there is friction ({numref}`Figure {number} <1k1004/figure_1.png>`), then, as the stick falls, the tip does not slip. The horizontal friction force causes a horizontal momentum, which increases during the fall.The velocity vector of the center of mass of the stick is approaching a vertical orientation as the stick nears the floor. In the beginning the velocity of the center of mass is increasing in the horizontal direction, but since this velocity is becoming more vertical, something must happen to maintain the horizontal momentum. As a result, the stick does not continue to rotate simply about its tip, but takes on a horizontal translational velocity in the direction of the fall.
+When there is friction ({numref}`Figure {number} <1k1004_figure_1.png>`), then, as the stick falls, the tip does not slip. The horizontal friction force causes a horizontal momentum, which increases during the fall.The velocity vector of the center of mass of the stick is approaching a vertical orientation as the stick nears the floor. In the beginning the velocity of the center of mass is increasing in the horizontal direction, but since this velocity is becoming more vertical, something must happen to maintain the horizontal momentum. As a result, the stick does not continue to rotate simply about its tip, but takes on a horizontal translational velocity in the direction of the fall.
## Remarks
Students can perform the demonstration themselves using a pencil. For the first demonstration, the sharpened pencil rests with its point on a glass surface. For the second demonstration, the pencil rests with its rubber top on a piece of sandpaper.
diff --git a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md
index a51c1575..e587bd0a 100644
--- a/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md
+++ b/book/book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k1005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k1005_figure_0.png
+
.
```
@@ -25,20 +24,19 @@ name: 1k1005/figure_0.png
## Presentation
The lines on the basketball make it easy to see if the ball rotates yes or no.
-Throw the basketball and observe that before hitting the ground it does not rotate, but that after rebound it rotates (see {numref}`Figure {number} <1k1005/figure_1.png>`A).
+Throw the basketball and observe that before hitting the ground it does not rotate, but that after rebound it rotates (see {numref}`Figure {number} <1k1005_figure_1.png>`A).
+
+Also can be observed that after rebound the ball moves steeper than when it was in the throw (again: see {numref}`Figure {number} <1k1005_figure_1.png>`A).
-Also can be observed that after rebound the ball moves steeper than when it was in the throw (again: see {numref}`Figure {number} <1k1005/figure_1.png>`A).
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1k1005_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1k1005/figure_1.png
----
.
```
## Explanation
-The ball has an impulse $p$, which can be looked at as consisting of a vertical component $p_{\nu}$ and a horizontal component $p_{h}$. When the ball hits the ground, $p_{\nu}$ is reversed (supposing complete elasticity). But $p_{h}$ changes because the friction force $F_{R}$, that acts during a short time ( $\Delta t$ ), reduces the horizontal impulse by an amount of $\Delta \vec{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$. The combination of unchanged $p_{v}$ and changed $p_{h}$ makes that the ball mounts steeper (Figure {numref}`Figure {number} <1k1005/figure_1.png>`C).
+The ball has an impulse $p$, which can be looked at as consisting of a vertical component $p_{\nu}$ and a horizontal component $p_{h}$. When the ball hits the ground, $p_{\nu}$ is reversed (supposing complete elasticity). But $p_{h}$ changes because the friction force $F_{R}$, that acts during a short time ( $\Delta t$ ), reduces the horizontal impulse by an amount of $\Delta \vec{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$. The combination of unchanged $p_{v}$ and changed $p_{h}$ makes that the ball mounts steeper (Figure {numref}`Figure {number} <1k1005_figure_1.png>`C).
That it rotates as well is due to the torque during contact with the ground, changing its angular momentum by an amount of: $\Delta \vec{L}=\int_{0}^{\Delta t} \vec{r} \times \vec{F} d t$.
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2001 Braking/1K2001.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2001 Braking/1K2001.md
index 79e4bbfc..9eef56f5 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2001 Braking/1K2001.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2001 Braking/1K2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2001_figure_0.png
+
.
```
@@ -26,37 +25,26 @@ name: 1k2001/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/PmLqxyRhAvI?si=1mPK_6xDiM70t476
+```
+
+Roll cart 1 down the incline (all wheels free) and ask the audience: "In case of rolling down an incline is it advisable to have braking (or better: "blocking"), on the rear wheels or on the front wheels, in order to have a controlled descent?" Most people guess: “rear wheels” or “doesn’t it matter which wheels you block”. Then place cart 2 with the blocked wheels at the rear, on the inclined board and permit it to go down. During this run the car reverses itself and slides down rear end first (skidding). See {numref}`Figure {number} <1k2001_figure_1.png>`.
-Roll cart 1 down the incline (all wheels free) and ask the audience: "In case of rolling down an incline is it advisable to have braking (or better: "blocking"), on the rear wheels or on the front wheels, in order to have a controlled descent?" Most people guess: “rear wheels” or “doesn’t it matter which wheels you block”. Then place cart 2 with the blocked wheels at the rear, on the inclined board and permit it to go down. During this run the car reverses itself and slides down rear end first (skidding). See {numref}`Figure {number} <1k2001/figure_1.png>`.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2001/figure_1.png
----
.
```
If the blocked wheels are at the front, the car slides down without skidding. It stays inline on the inclined plane. See Figure A in Diagram: The cart had its blocked wheels in front and is launched under a small angle with the direction of the inclined plane. During its run it lines up into the direction of the inclined plane.
## Explanation
-When a wheel is rolling, it is governed by static friction. When a wheel is sliding, it is governed by kinetic friction. The coefficient of static friction is higher than the coefficient of kinetic friction (see, for instance, the demonstration "Sliding towel" in this database). {numref}`Figure {number} <1k2001/figure_2.png>` shows the effect of this on the cart in case of blocked wheels at the rear: The frictional force at the rear wheels is lower than that on the front wheels (supposing equal normal forces on the wheels), and so the resultant force into the downward direction along the plane is highest on the rear wheels. This means a higher acceleration along the plane and in due time the rear wheels will overtake the front wheels.
+When a wheel is rolling, it is governed by static friction. When a wheel is sliding, it is governed by kinetic friction. The coefficient of static friction is higher than the coefficient of kinetic friction (see, for instance, the demonstration "Sliding towel" in this database). {numref}`Figure {number} <1k2001_figure_2.png>` shows the effect of this on the cart in case of blocked wheels at the rear: The frictional force at the rear wheels is lower than that on the front wheels (supposing equal normal forces on the wheels), and so the resultant force into the downward direction along the plane is highest on the rear wheels. This means a higher acceleration along the plane and in due time the rear wheels will overtake the front wheels.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k2001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k2001/figure_2.png
----
.
```
@@ -66,7 +54,7 @@ Now it will be easy to explain also the situation of blocked front wheels. In th
- Students experience the most difficulty with the fact that a rolling wheel means static friction. So stress in your explanation that the local velocity of a rolling wheel at the point of contact with the road is zero. (see Sources: The Physics Teacher)
- The demo can also be done on the ground giving the cart a push. (But then students sometimes think that you trick them in the way of pushing.)
- This demonstration also leads to the answer on questions like "Should you lock your brakes when sliding?" and "Why should you steer into a skid?".
-- Due to the geometry of the demonstration the normal forces on the front - and rear wheels are not equal: The normal force on the front wheels is higher than the normal force on the rear wheels. In case of locking the rear wheels the difference in the friction forces (see {numref}`Figure {number} <1k2001/figure_2.png>`) is still larger and so the skidding effect will be even stronger. But in the situation where we lock the front wheels, the difference between the normal forces is contra-productive (even a front wheel lock can then produce a skid). The longer the car, the smaller the difference between the normal forces: so use a relatively long car to have a successful demonstration. (Having done the demonstration with a long car it can be stimulating to do it also with a short one.)
+- Due to the geometry of the demonstration the normal forces on the front - and rear wheels are not equal: The normal force on the front wheels is higher than the normal force on the rear wheels. In case of locking the rear wheels the difference in the friction forces (see {numref}`Figure {number} <1k2001_figure_2.png>`) is still larger and so the skidding effect will be even stronger. But in the situation where we lock the front wheels, the difference between the normal forces is contra-productive (even a front wheel lock can then produce a skid). The longer the car, the smaller the difference between the normal forces: so use a relatively long car to have a successful demonstration. (Having done the demonstration with a long car it can be stimulating to do it also with a short one.)
## Sources
- Lewett Jr., John W., Physics Begins With an M... Mysteries, Magic, and Myth, pag. 40.
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2002 Phonebook Friction/1K2002.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2002 Phonebook Friction/1K2002.md
index ad26438c..ebcf0f9f 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2002 Phonebook Friction/1K2002.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2002 Phonebook Friction/1K2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2002_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2004 Falling Stick/1K2004.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2004 Falling Stick/1K2004.md
index 8a4e2cf4..71d4c5b9 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2004 Falling Stick/1K2004.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2004 Falling Stick/1K2004.md
@@ -1,3 +1,3 @@
-```{include} /book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md
+```{include} ../../1K10 Dynamic Torque/1K1004 Falling Stick/1K1004.md
```
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2005 Throwing a Basketball/1K2005.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2005 Throwing a Basketball/1K2005.md
index 4b37e358..3e52130e 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2005 Throwing a Basketball/1K2005.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2005 Throwing a Basketball/1K2005.md
@@ -1,4 +1,4 @@
-```{include} /book/1 mechanics/1K apply newton/1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md
+```{include} ../../1K10 Dynamic Torque/1K1005 Throwing a Basketball/1K1005.md
```
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2006 Chain Friction/1K2006.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2006 Chain Friction/1K2006.md
index 618be2bd..f35691d9 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2006 Chain Friction/1K2006.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2006 Chain Friction/1K2006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2006_figure_0.png
+
.
```
@@ -27,13 +26,12 @@ name: 1k2006/figure_0.png
The chain is laid out straight on a table. One end is slowly pulled over the edge until the chain just does not slip. The coefficient of friction $\left(\mu_{s}\right)$ between the table top and chain is then $\mu_{s}=\frac{l_{0}}{l-l_{0}}$, where $l$ is the total length of the chain and $l_{0}$ the length of the overhanging portion.
## Explanation
-No slipping means that forces are in equilibrium: $F_{1}=F_{2}$ (see {numref}`Figure {number} <1k2006/figure_1.png>`).
+No slipping means that forces are in equilibrium: $F_{1}=F_{2}$ (see {numref}`Figure {number} <1k2006_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2006_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2006/figure_1.png
----
.
```
The mass of the part of the chain hanging over the edge equals: $m_{1}=\frac{l_{0}}{l} m$. This makes: $l_{0} F_{1}=\frac{l_{0}}{l} m g$.
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/1K2007.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/1K2007.md
index 267ca729..8cbfe144 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/1K2007.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/1K2007.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2007_figure_0.png
+
.
```
@@ -36,13 +35,12 @@ Initially the stick exerts the same force on both fingers. When the fingers are
This is independent of the starting-point of the fingers and also independent of the type of friction.
-According to the second condition for equilibrium, the fractions of the meterstick's weight resting on your two fingers, $W_{1}$ and $W_{2}$, depend on the distances $x_{1}$ and $x_{2}$ to the centre, according to the relation $W_{1} x_{1}=W_{2} x_{2}$. Just at the point where one finger stops moving and the other starts moving, the static-friction force of the fixed finger equals the kinetic-friction force of the moving finger: $\mu_{s} W_{1}=\mu_{k} W_{2}$ (see {numref}`Figure {number} <1k2007/figure_1.png>`).
+According to the second condition for equilibrium, the fractions of the meterstick's weight resting on your two fingers, $W_{1}$ and $W_{2}$, depend on the distances $x_{1}$ and $x_{2}$ to the centre, according to the relation $W_{1} x_{1}=W_{2} x_{2}$. Just at the point where one finger stops moving and the other starts moving, the static-friction force of the fixed finger equals the kinetic-friction force of the moving finger: $\mu_{s} W_{1}=\mu_{k} W_{2}$ (see {numref}`Figure {number} <1k2007_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2007_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2007/figure_1.png
----
.
```
Combining the two preceding equations yields the condition $\mu_{k} x_{1}=\mu_{s} x_{2}$. By observing just where one finger stops sliding and the other starts, you can measure the values of $x_{1}$ and $x_{2}$, and thereby determine the ratio of the two friction coefficients using $\mu_{k} / \mu_{s}=x_{2} / x_{1}$.
@@ -54,7 +52,6 @@ You can, of course, make your fingers meet at some point other than the half-way
```{iframe} https://www.youtube.com/watch?v=-iS4XH6hcqs
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/qr_images/qrcode_watch_v__iS4XH6hcqs.svg b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/qr_images/qrcode_watch_v__iS4XH6hcqs.svg
new file mode 100644
index 00000000..a00d9e16
--- /dev/null
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2007 Moving Two Fingers under a Meterstick/qr_images/qrcode_watch_v__iS4XH6hcqs.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2008 No Tipping Allowed/1K2008.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2008 No Tipping Allowed/1K2008.md
index 8a036d15..26af9320 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2008 No Tipping Allowed/1K2008.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2008 No Tipping Allowed/1K2008.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2008/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2008_figure_0.png
+
.
```
@@ -35,42 +34,32 @@ name: 1k2008/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/pQoVApmwdNY?si=xM65rjpKTJKm_dpN
+:width: 70%
+```
The lateral standing cylinder is given a push by hand. (Push the cylinder on the bottom half, a number of times from left to right and vice versa).
Cylinder $l_{1}$ never tips, $l_{5}$ always tips, $l_{2}, l_{3}$ and $l_{4}$ tip sometimes/often ( $l_{3}$ tips roughly $50 \%$ of the times).
## Explanation
- On the verge of tipping, the upward normal force acts at the leading edge of the base ({numref}`Figure {number} <1k2008/figure_1.png>`, point A).
+ On the verge of tipping, the upward normal force acts at the leading edge of the base ({numref}`Figure {number} <1k2008_figure_0.png>`, point A).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2008_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2008/figure_1.png
----
.
```
-In the decelerating reference frame ma acts on the center of mass, along with the vertical gravitational force mg. (See {numref}`Figure {number} <1k2008/figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k2008/figure_2.png
----
+In the decelerating reference frame ma acts on the center of mass, along with the vertical gravitational force mg. (See {numref}`Figure {number} <1k2008_figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k2008_figure_2.png
+
.
```
-When the resultant of $ma$ and $mg$ is directed to point $\mathrm{A}$, the cylinder is on the verge of tipping. {numref}`Figure {number} <1k2008/figure_2.png>` shows that in that case $\mu_{k}=d / h$.
+When the resultant of $ma$ and $mg$ is directed to point $\mathrm{A}$, the cylinder is on the verge of tipping. {numref}`Figure {number} <1k2008_figure_2.png>` shows that in that case $\mu_{k}=d / h$.
## Remarks
When constructing the demonstration, you need to know the value of $\mu_{k}$ before you can cut the cylinder to the proper heights. $\mu_{k}$ can easily be determined by placing a short cylinder on an inclined board and finding the angle of incline for which the cylinder slides at constant speed after being given an initial push. $\mu_{k}=\tan (\alpha)$ ( $\alpha=$ angle of incline).
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2009 Pulling a Sliding Block/1K2009.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2009 Pulling a Sliding Block/1K2009.md
index ff6227f5..34c31494 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2009 Pulling a Sliding Block/1K2009.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2009 Pulling a Sliding Block/1K2009.md
@@ -7,11 +7,10 @@ Showing the difference between static and kinetic friction
* 1K20 (Friction)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2009/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2009_figure_0.png
+
.
```
@@ -25,13 +24,12 @@ name: 1k2009/figure_0.png
The slotted mass is made so heavy that the block just doesn’t move. Then you give a smash on the table and the block will start sliding and keep on sliding.
## Explanation
-When the block just doesn't move, it means that $F_{f}$ is almost equal to $F_{f, \max }=\mu_{\text {stat }} F_{n}$ (see {numref}`Figure {number} <1k2009/figure_1>`).
+When the block just doesn't move, it means that $F_{f}$ is almost equal to $F_{f, \max }=\mu_{\text {stat }} F_{n}$ (see {numref}`Figure {number} <1k2009_figure_1>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2009_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2009/figure_1
----
.
```
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2010 Rolling Up and Down Again and Again/1K2010.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2010 Rolling Up and Down Again and Again/1K2010.md
index d36216a4..12520a77 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2010 Rolling Up and Down Again and Again/1K2010.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2010 Rolling Up and Down Again and Again/1K2010.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2010/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2010_figure_0.png
+
.
```
@@ -30,13 +29,12 @@ Release the ball and it will roll down the track, climb the other track, and so
After $\mathrm{n}$ runs the coefficient of rolling friction can be determined by measuring the distance the ball travels upward in the $\mathrm{n}$-th run.
## Explanation
- The potential energy of the ball equals (see {numref}`Figure {number} <1k2010/figure_1.png>` and {numref}`Figure {number} <1k2010/figure_2.png>`)
+ The potential energy of the ball equals (see {numref}`Figure {number} <1k2010_figure_1.png>` and {numref}`Figure {number} <1k2010_figure_2.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2010_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2010/figure_1.png
----
.
```
$U_{p}(0)=m g s_{0} \sin (\alpha)=F s_{0}$
@@ -53,13 +51,12 @@ $s_{2}=s_{1} \cdot b=s_{0} \cdot b^{2}$
The coefficient of friction $(\mu)$ is by definition $F_{f} / F_{N}$.
-In this case (see {numref}`Figure {number} <1k2010/figure_2.png>`): $\mu=\frac{F_{f}}{F} \tan \alpha$.
+In this case (see {numref}`Figure {number} <1k2010_figure_2.png>`): $\mu=\frac{F_{f}}{F} \tan \alpha$.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1k2010_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1k2010/figure_2.png
----
.
```
So the coefficient of friction can be determined by measuring $s_{0}, s_{2}$ and $\alpha$ and using the formulas above.
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2011 Rope on a Table/1K2011.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2011 Rope on a Table/1K2011.md
index dfa32bfc..12834ac6 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2011 Rope on a Table/1K2011.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2011 Rope on a Table/1K2011.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2011/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2011_figure_0.png
+
.
```
@@ -28,13 +27,12 @@ name: 1k2011/figure_0.png
Ask the audience in what order the loops tighten to knots when pulling the ends of the rope.
- Then perform the experiment and carefully observe that the largest loop always moves first, ending in closing all together at the same moment (see {numref}`Figure {number} <1k2011/figure_1.png>`).
+ Then perform the experiment and carefully observe that the largest loop always moves first, ending in closing all together at the same moment (see {numref}`Figure {number} <1k2011_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1k2011_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1k2011/figure_1.png
----
.
```
2. The rope with loops of different sizes is hung horizontally. Again ask the audience in what order the loops will tighten to knots when pulling the ends of the rope. Then perform the experiment and observe that the small loops move first to knots and the largest loops last!
diff --git a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2012 Sliding Towel/1K2012.md b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2012 Sliding Towel/1K2012.md
index b14210a1..35ef65c7 100644
--- a/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2012 Sliding Towel/1K2012.md
+++ b/book/book/1 mechanics/1K apply newton/1K20 Friction/1K2012 Sliding Towel/1K2012.md
@@ -4,17 +4,8 @@
## Aim
Showing the difference between static and dynamic coefficient of friction.
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/8SAOsvKrJk8
+```
## Subjects
* 1K20 (Friction)
@@ -22,11 +13,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1k2012/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1k2012_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/1L1001.md b/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/1L1001.md
index e12d17c3..5c886d33 100644
--- a/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/1L1001.md
+++ b/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/1L1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1l1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1l1001_figure_0.png
+
.
```
@@ -30,13 +29,12 @@ name: 1l1001/figure_0.png
## Presentation
First a short historical survey is presented to the students:
-- **1687:** Newton's law on gravitation published in his “Philosophia Naturalis Principia". In this "Principia" he considers that the attraction of a pendulum (that hangs straight downwards) by a mountain could be used as a practical demonstration of his theory (see {numref}`Figure {number} <1l1001/figure_1.png>`), but pessimistically he thought that any real mountain would produce too small a deflection to measure.
+- **1687:** Newton's law on gravitation published in his “Philosophia Naturalis Principia". In this "Principia" he considers that the attraction of a pendulum (that hangs straight downwards) by a mountain could be used as a practical demonstration of his theory (see {numref}`Figure {number} <1l1001_figure_1.png>`), but pessimistically he thought that any real mountain would produce too small a deflection to measure.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1l1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1l1001/figure_1.png
----
.
```
@@ -45,36 +43,33 @@ name: 1l1001/figure_1.png
* **1774**: The plumb-line experiment is conducted around the Scottish mountain of Schiehallion. A deflection of 11.6 seconds of arc is measured (the sum of the north - and south deflections). Based on these measurements Hutton determined in 1778 that the earth had a mean density of about 9/5 of that of the mountain, and announced that the mean density of the Earth is $4,500 \mathrm{~kg} / \mathrm{m}^{-3}$. He also gives a density table for the other planets and the Sun.
* **1783**: John Michell, a geologist, invents the torsion balance (independent of Coulomb in France) in order to measure the force of gravity between masses in the laboratory. He dies in 1793 before he could begin the experiment. His apparatus was sent to Cavendish who performed and completed the experiment in 1798.
- Pictures of Cavendish balance are shown to the students (see {numref}`Figure {number} <1l1001/figure_1.png>`).
+ Pictures of Cavendish balance are shown to the students (see {numref}`Figure {number} <1l1001_figure_1.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1l1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1l1001/figure_2.png
----
.
```
Our instrument (see Diagram B) is explained to the students and compared with Cavendish's construction:
-It is essentially a torsion pendulum in which two small lead balls ( 15 gram each) rest on the ends of a light aluminium boom. This boom is suspended in the centre by a thin tungsten wire (diameter is 25 micron). All this is mounted inside a draft proof case. On the outside of the case two larger lead balls (1 kilogram each) can be swivelled from one side to the other (see {numref}`Figure {number} <1l1001/figure_3.png>`).
+It is essentially a torsion pendulum in which two small lead balls ( 15 gram each) rest on the ends of a light aluminium boom. This boom is suspended in the centre by a thin tungsten wire (diameter is 25 micron). All this is mounted inside a draft proof case. On the outside of the case two larger lead balls (1 kilogram each) can be swivelled from one side to the other (see {numref}`Figure {number} <1l1001_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1l1001_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1l1001/figure_3.png
----
.
```
-The position of the boom is measured in a capacitive way: the boom is suspended between capacitor plates mounted in the aluminium case. This transducer comprises two sensors to eliminate noise due to vibrations. The transducer output is proportional to the angular movement of the boom. The angular displacement appears on the monitor screen as a function of time (see {numref}`Figure {number} <1l1001/figure_4.png>`).
+The position of the boom is measured in a capacitive way: the boom is suspended between capacitor plates mounted in the aluminium case. This transducer comprises two sensors to eliminate noise due to vibrations. The transducer output is proportional to the angular movement of the boom. The angular displacement appears on the monitor screen as a function of time (see {numref}`Figure {number} <1l1001_figure_4.png>`).
+
+At the beginning of the lecture a small displacement of the boom is given (for instance by a little "shock" to the table). It takes quite a long time before the boom is at rest again (see the example in {numref}`Figure {number} <1l1001_figure_4.png>`, in which it took around 3000 seconds before the boom was damped enough to perform the demonstration). In this damping the students can clearly observe the torsional vibration of the boom.
-At the beginning of the lecture a small displacement of the boom is given (for instance by a little "shock" to the table). It takes quite a long time before the boom is at rest again (see the example in {numref}`Figure {number} <1l1001/figure_4.png>`, in which it took around 3000 seconds before the boom was damped enough to perform the demonstration). In this damping the students can clearly observe the torsional vibration of the boom.
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 1l1001_figure_4.png
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 1l1001/figure_4.png
----
.
```
(Giving the model torsion-balances a small deflection will strengthen their imagination of what is happening inside the casing of our instrument.)
@@ -83,7 +78,7 @@ In $\mathrm{P}-\mathrm{Q}$ we swivel the lead balls in the right rhythm from one
## Explanation
-***The mountain experiment (see {numref}`Figure {number} <1l1001/figure_1.png>`):***
+***The mountain experiment (see {numref}`Figure {number} <1l1001_figure_1.png>`):***
$F=G \frac{m M_{M}}{d^{2}}$ And $W=G \frac{m M_{E}}{r_{E}^{2}}$. This leads to: $\frac{F}{W}=\frac{M_{M}}{M_{E}}\left(\frac{r_{E}}{d}\right)^{2}=\frac{\rho_{M} V_{M}}{\rho_{E} V_{E}}\left(\frac{r_{E}}{d}\right)^{2}$
@@ -111,7 +106,6 @@ In this way Cavendish found that the Earth's density is 5.448 times that of wate
```{iframe} https://www.youtube.com/watch?v=4DlyZL436hE
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/qr_images/qrcode_watch_v_4DlyZL436hE.svg b/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/qr_images/qrcode_watch_v_4DlyZL436hE.svg
new file mode 100644
index 00000000..3fbf0dfa
--- /dev/null
+++ b/book/book/1 mechanics/1L gravity/1L10 Universal G/1L1001 Weighing the Earth/qr_images/qrcode_watch_v_4DlyZL436hE.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2001 Kepler 2/1L2001.md b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2001 Kepler 2/1L2001.md
index 7d03b943..e6e605c5 100644
--- a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2001 Kepler 2/1L2001.md
+++ b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2001 Kepler 2/1L2001.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1l2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1l2001_figure_0.png
+
.
```
@@ -27,13 +26,12 @@ name: 1l2001/figure_0.png
## Presentation
- By means of the software program an elliptical orbit is projected (see {numref}`Figure {number} <1l2001/figure_1.png>`A). The speed in the orbit is visualized when in the orbit points are plotted at constant time-intervals. This orbit is also plotted when the time-interval applied is 16 times larger ({numref}`Figure {number} <1l2001/figure_1.png>`B).
+ By means of the software program an elliptical orbit is projected (see {numref}`Figure {number} <1l2001_figure_1.png>`A). The speed in the orbit is visualized when in the orbit points are plotted at constant time-intervals. This orbit is also plotted when the time-interval applied is 16 times larger ({numref}`Figure {number} <1l2001_figure_1.png>`B).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1l2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1l2001/figure_1.png
----
.
```
@@ -42,15 +40,14 @@ Before, we had this figure projected on a large sheet of cardboard and the ellip
## Explanation
Kepler "found" his law while working on the astronomical data of Tycho Brahe. So in our demonstration the law should arise from watching the areas and "seeing" the equality. Since Newton we can use the law of conservation of angular momentum. Using this law we can explain the statement of Kepler's second law.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1l2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1l2001_figure_2.png
+
.
```
-Consider the area in {numref}`Figure {number} <1l2001/figure_2.png>` swept by the vector $r$ in a time $\Delta t$.
+Consider the area in {numref}`Figure {number} <1l2001_figure_2.png>` swept by the vector $r$ in a time $\Delta t$.
$$\Delta A = \frac{1}{2}\left| \vec{r} \times \Delta\vec{ r}\right|$$
$$\frac{\Delta A}{\Delta t} = \frac{1}{2}\left| \vec{r} \times \frac{\Delta \vec{r}}{\Delta t}\right|=\frac{1}{2}\left| \vec{r} \times \Delta \vec{v}\right|$$
diff --git a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L20.02 Kepler's Third Law.ipynb b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L20.02 Kepler's Third Law.ipynb
deleted file mode 100644
index 506552cb..00000000
--- a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L20.02 Kepler's Third Law.ipynb
+++ /dev/null
@@ -1,168 +0,0 @@
-{
- "cells": [
- {
- "cell_type": "markdown",
- "metadata": {},
- "source": [
- "\n",
- "```{figure} /figures/ready.png\n",
- "---\n",
- "width: 35%\n",
- "align: right\n",
- "```\n",
- "# 02 Kepler's Third Law \n",
- " \n",
- " \n",
- "## Aim \n",
- " To show empirically that Kepler’s third law is true. \n",
- " \n",
- "## Subjects \n",
- " 1L20 (Orbits) 8A10 (Solar System Mechanics) \n",
- " \n",
- "
-## Diagram \n",
- " \n",
- "```{figure} figures/figure_0.png \n",
- "--- \n",
- "width: 70% \n",
- "name: 1l2002/figure_0.png \n",
- "--- \n",
- " \n",
- "``` \n",
- " \n",
- " \n",
- "## Equipment \n",
- " \n",
- " * Graph on overhead sheet, $T=f(a)$, $T$ and a both scaled logarithmically. \n",
- " * Table with data of the planetary system (see [Sources](#sources)). \n",
- " \n",
- "## Presentation \n",
- " The graph is projected by means of an overhead sheet. The relationship with the table of planetary data is elucidated. Clearly can be observed that the data fit on a straight line in such a double logarithmic graph. The slope of this line ($p/q$) equals 1.5. This is the relationship of the powers in Kepler's third law: $T^2\\propto a^3$\n",
- " \n",
- "## Explanation \n",
- " Kepler's third law states $T^2=c \\times a^3$ with $c$ a constant. Taking logarithms on both sides, we can also write:\n",
- " $$2\\log T = \\log c + 3\\log a$$ \n",
- " and:\n",
- " $$\\log T = \\frac{1}{2}\\log c + \\frac{3}{2}\\log a$$\n",
- " So when T and a are graphed logarithmically (with $x$– and $y$-decades equally spaced), we see a line whose slope ($\\frac{3}{2}$) is the power-relationship in the original function. \n",
- "\n",
- "## Simulation.\n",
- "For the simulation we use the planets in our solar system. Additional data points can also be added."
- ]
- },
- {
- "cell_type": "code",
- "execution_count": 3,
- "metadata": {},
- "outputs": [
- {
- "data": {
- "image/png": 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",
- "text/plain": [
- "
"
- ]
- },
- "metadata": {},
- "output_type": "display_data"
- }
- ],
- "source": [
- "import numpy as np\n",
- "import matplotlib.pyplot as plt\n",
- "\n",
- "#Planetary data: name of planet, average distance to the sun(AU), Orbital period (years)\n",
- "planet_data = np.array([\n",
- " [\"Mercury\", 0.39, 0.24],\n",
- " [\"Venus\", 0.72, 0.61],\n",
- " [\"Earth\", 1.00, 1.00],\n",
- " [\"Mars\", 1.52, 1.88],\n",
- " [\"Jupiter\", 5.20, 11.86],\n",
- " [\"Saturn\", 9.58, 29.46],\n",
- " [\"Uranus\", 19.22, 84.01],\n",
- " [\"Neptune\", 30.05, 164.80]\n",
- "])\n",
- "\n",
- "# Convert the second and third columns to floats\n",
- "distances = planet_data[:, 1].astype(float)\n",
- "orbital_periods = planet_data[:, 2].astype(float)\n",
- "\n",
- "# Plot the data\n",
- "plt.plot(distances, orbital_periods, 'o')\n",
- "plt.xlabel('Average Distance to Sun $a$ (AU)')\n",
- "plt.ylabel('Orbital Period $T$ (years)')\n",
- "plt.yscale('log')\n",
- "plt.xscale('log')\n",
- "plt.title('Kepler\\'s Third Law')\n",
- "plt.show()\n"
- ]
- },
- {
- "cell_type": "markdown",
- "metadata": {},
- "source": [
- "The figure above plots both $T$ and $a$ linearly. We can now try to empirically validate Kepler's third law by fitting a straight line $\\log T= h\\times \\log a + const.$ to the data using linear regression. If Kepler's third law is correct we should find a value of 3/2 for h."
- ]
- },
- {
- "cell_type": "code",
- "execution_count": 19,
- "metadata": {},
- "outputs": [
- {
- "name": "stdout",
- "output_type": "stream",
- "text": [
- "h = 1.5011 ± 0.0013\n",
- "0.0013\n"
- ]
- }
- ],
- "source": [
- "from scipy.optimize import curve_fit\n",
- "\n",
- "def fit(a, h, const):\n",
- " return h*a+const\n",
- "\n",
- "distances_log = np.log(distances)\n",
- "orbital_periods_log = np.log(orbital_periods)\n",
- "\n",
- "popt, pcov = curve_fit(fit, distances_log, orbital_periods_log)\n",
- "print('h = ' + str(round(popt[0],4)) + ' ± ' + str(round(np.sqrt(pcov[0,0]),4)))\n"
- ]
- },
- {
- "cell_type": "markdown",
- "metadata": {},
- "source": [
- "## Sources \n",
- " \n",
- " * Mansfield, M and O'Sullivan, C., Understanding physics, edition 1998, pag. 106-107 and 741 (planetary data). \n",
- " * BINAS tabellenboek, vijfde druk, tabel 31. \n",
- " * McComb, W.D., Dynamics and Relativity, edition 1999, pag. 72-74. \n",
- " * Roest, R., Inleiding Mechanica, vijfde druk, pag. 257-258. \n",
- " * Stewart, J, Calculus, edition 1999, pag. 867."
- ]
- }
- ],
- "metadata": {
- "kernelspec": {
- "display_name": "base",
- "language": "python",
- "name": "python3"
- },
- "language_info": {
- "codemirror_mode": {
- "name": "ipython",
- "version": 3
- },
- "file_extension": ".py",
- "mimetype": "text/x-python",
- "name": "python",
- "nbconvert_exporter": "python",
- "pygments_lexer": "ipython3",
- "version": "3.11.7"
- }
- },
- "nbformat": 4,
- "nbformat_minor": 2
-}
diff --git a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L2002.md b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L2002.md
index 43363764..15a6dced 100644
--- a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L2002.md
+++ b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2002 Kepler 3/1L2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1l2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1l2002_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2003 Precessing Orbit/1L2003.md b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2003 Precessing Orbit/1L2003.md
index 0d603163..46ae2155 100644
--- a/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2003 Precessing Orbit/1L2003.md
+++ b/book/book/1 mechanics/1L gravity/1L20 Orbits/1L2003 Precessing Orbit/1L2003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1l2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1l2003_figure_0.png
+
.
```
@@ -41,21 +40,20 @@ For the concave bowl we can write for this type of potential (Maclaurin series):
$$U(r)=U(0)+\frac{U^{'}(0)}{1!} r+\frac{U^{''}(0)}{2!} r^{2}+\frac{U^{'''}(0)}{3!} r^{3}+\ldots$$
-When $U(0)=0$ and $U^{'}(0)=0$ (minimum at $r=0$, the center of the bowl) and when $r$ is relatively small, so we can neglect the higher-order terms, then: $U(r)=\frac{1}{2} U "(0) r^{2}$.
+When $U(0)=0$ and $U^{'}(0)=0$ (minimum at $r=0$, the center of the bowl) and when $r$ is relatively small, so we can neglect the higher-order terms, then: $U(r)=\frac{1}{2} U^{''}(0) r^{2}$.
This is a harmonic potential, and when moving in a line with small amplitudes, we'll see a harmonic motion. This harmonic potential $\left(r^{2}\right)$ is clearly NOT a $r^{-1}$-potential.
-```{figure} figures/figure_1.png
----
-width: 60%
-name: 1l2003/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 60%
+:label: 1l2003_figure_1.png
+
.
```
In case of an ellipse, the situation becomes even worse. Now one focus of the ellipse is off the center of the bowl (see Figure 1) and at $r=0, U(0)=0$, but $U^{'}(0)$ is not 0 ! So now:
-$$U(r)=U^{'}(0) r+\frac{1}{2} U^{' '}(0) r^{2}+\frac{1}{6} U^{' ' '}(0) r^{3} \ldots$$
+$$U(r)=U^{'}(0) r+\frac{1}{2} U^{''}(0) r^{2}+\frac{1}{6} U^{'''}(0) r^{3} \ldots$$
showing that expressing the potential with respect to a focal point, this potential is still farther away from a $r^{-1}$-potential. Conclusion is that the bowl only suggests planetary motion (but is in the same time a wrong example of such a motion). The only reason to show it, is to challenge the mind of the students with the question how the shape of the bowl ought to be for a real $r^{-1}$- potential.
diff --git a/book/book/1 mechanics/1M work and energy/1M10 Work/1M1001 How much Work to Break a Soup Tureen/1M1001.md b/book/book/1 mechanics/1M work and energy/1M10 Work/1M1001 How much Work to Break a Soup Tureen/1M1001.md
index 450ce53d..c03b44e0 100644
--- a/book/book/1 mechanics/1M work and energy/1M10 Work/1M1001 How much Work to Break a Soup Tureen/1M1001.md
+++ b/book/book/1 mechanics/1M work and energy/1M10 Work/1M1001 How much Work to Break a Soup Tureen/1M1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1m1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1m1001_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/1M4001.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/1M4001.md
index 2aa22b93..e54533ff 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/1M4001.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/1M4001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1m4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1m4001_figure_0.png
+
.
```
@@ -24,44 +23,33 @@ name: 1m4001/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/vePptER5zUc?si=UgN5kZFlR_NNiTvR
+```
***Introduction***
- Place one steel ball on the rail. A second ball slowly rolls towards it and there is a collision. The first ball stops and the second ball rolls with a speed equal to that of the starting ball (see {numref}`Figure {number} <1m4001/figure_1.png>`A). Place three steel balls on the rail, touching each other. A fourth ball rolls towards them and there is a collision. The fourth ball stops and the third ball moves away with a speed equal to that of the fourth ball (see {numref}`Figure {number} <1m4001/figure_1.png>`B).
+ Place one steel ball on the rail. A second ball slowly rolls towards it and there is a collision. The first ball stops and the second ball rolls with a speed equal to that of the starting ball (see {numref}`Figure {number} <1m4001_figure_1.png>`A). Place three steel balls on the rail, touching each other. A fourth ball rolls towards them and there is a collision. The fourth ball stops and the third ball moves away with a speed equal to that of the fourth ball (see {numref}`Figure {number} <1m4001_figure_1.png>`B).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1m4001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1m4001/figure_1.png
----
.
```
***Presentation***
-A ceramic magnet is added to the setup and firmly fixed to the rail (see {numref}`Figure {number} <1m4001/figure_1.png>`C). The fourth ball slowly rolls towards the ceramic magnet, hits and ball three rolls away with a much higher speed!
+A ceramic magnet is added to the setup and firmly fixed to the rail (see {numref}`Figure {number} <1m4001_figure_1.png>`C). The fourth ball slowly rolls towards the ceramic magnet, hits and ball three rolls away with a much higher speed!
-When in {numref}`Figure {number} <1m4001/figure_1.png>`C ball 4 is stuck to the magnet, the approaching ball 3 will not launch ball 4.
+When in {numref}`Figure {number} <1m4001_figure_1.png>`C ball 4 is stuck to the magnet, the approaching ball 3 will not launch ball 4.
The demonstration can be made more spectacular by placing more magnet-three-balls combinations, so that the speed increases more and more and more..., making a rifle!(?) (see Diagram B).
## Explanation
-The magnet exerts an attractive force on the steel balls. When a ball sticks to the magnet a force is needed to make it loose. In terms of potential energy the magnet is a well (see {numref}`Figure {number} <1m4001/figure_2.png>`).
+The magnet exerts an attractive force on the steel balls. When a ball sticks to the magnet a force is needed to make it loose. In terms of potential energy the magnet is a well (see {numref}`Figure {number} <1m4001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1m4001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1m4001/figure_2.png
----
.
```
Energy conservation enables a description of the begin- and end-situation (no matter how complicated the process in between). So we give a description of ball 4 and ball 3:
@@ -76,15 +64,15 @@ so, $K_{3}=K_{4}+U_{3}-U_{4}^{'}$
$U_{3}$ and $U_{4}^{'}$ are both negative and $\left[U_{4}\right]>\left[U_{3}\right]$, making $K_{3}^{'}>K_{4}$. Ball 3 has the same mass as ball 4 , so when $K_{3}>K_{4}$, then ball 3 moves faster than ball 4.
-{numref}`Figure {number} <1m4001/figure_2.png>` visualizes the energy conservation in such a way.
+{numref}`Figure {number} <1m4001_figure_2.png>` visualizes the energy conservation in such a way.
## Remarks
- The demonstration can also be done with 2 or 4 or more steel balls attached to the right side of the magnet. We have the most spectacular effect with three balls.
- The graph of potential energy of the magnetic field is drawn symmetrically. In reality it will be asymmetric, because when balls are attached to the magnet, the shape of the magnetic field will be changed, but it still holds that $\left|E_{\text {pot1 }}\right|>\left|E_{\text {pot } 2}\right|$ and the explanation remains the same.
- ***Extra demonstration***
- Is reversing the demonstration possible? (see {numref}`Figure {number} <1m4001/figure_1.png>`D). So, when rolling ball 3, can we launch ball 4 ?
+ Is reversing the demonstration possible? (see {numref}`Figure {number} <1m4001_figure_1.png>`D). So, when rolling ball 3, can we launch ball 4 ?
- The preceding demonstration suggests that to make that happen, ball 3 should have a high speed and 4 will be launched with a low speed (reverse the energy diagram of {numref}`Figure {number} <1m4001/figure_2.png>`). But this will not happen. No matter how high the speed of ball 3, ball 4 will never escape its potential energy well.
+ The preceding demonstration suggests that to make that happen, ball 3 should have a high speed and 4 will be launched with a low speed (reverse the energy diagram of {numref}`Figure {number} <1m4001_figure_2.png>`). But this will not happen. No matter how high the speed of ball 3, ball 4 will never escape its potential energy well.
When the high-speed ball 3 hits the magnet-combination it will easily rebound, leaving too little energy to launch ball 4. The best we can get is making ball 4 just moving a little to the left (climbing in its well), but then it accelerates quickly back to the magnet.
@@ -98,7 +86,6 @@ $U_{3}$ and $U_{4}^{'}$ are both negative and $\left[U_{4}\right]>\left[U_{3}\ri
```{iframe} https://www.youtube.com/watch?v=fiSd91sLtS4
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/qr_images/qrcode_watch_v_fiSd91sLtS4.svg b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/qr_images/qrcode_watch_v_fiSd91sLtS4.svg
new file mode 100644
index 00000000..bc9184c5
--- /dev/null
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4001 Gauss Rifle/qr_images/qrcode_watch_v_fiSd91sLtS4.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4002 Kinetic Energy in an Elastic Collision/1M4002.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4002 Kinetic Energy in an Elastic Collision/1M4002.md
index 31b80927..1dbad26d 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4002 Kinetic Energy in an Elastic Collision/1M4002.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4002 Kinetic Energy in an Elastic Collision/1M4002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1m4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1m4002_figure_0.png
+
.
```
@@ -26,13 +25,12 @@ name: 1m4002/figure_0.png
## Presentation
- Set up the equipment as shown in Diagram. Set up Scientific Workshop so that it shows four graphs: velocity of cart 1, kinetic energy of cart 1, kinetic energy of cart 2, sum of both kinetic energies (see {numref}`Figure {number} <1m4002/figure_1.png>`).
+ Set up the equipment as shown in Diagram. Set up Scientific Workshop so that it shows four graphs: velocity of cart 1, kinetic energy of cart 1, kinetic energy of cart 2, sum of both kinetic energies (see {numref}`Figure {number} <1m4002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1m4002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1m4002/figure_1.png
----
.
```
First show the elastic collision without using the data-acquisition system. Let the students observe that the velocities of cart 1 before the collision and of cart two after the collision are the same: conservation of kinetic energy. Do the demonstration again, but now collect data. On the screen the mentioned graphs appear. The results can be discussed. Observing the graph of $E_{kin,1}$ and $E_{kin,2}$ shows at first sight conservation of kinetic energy in this demonstration. But the graph of $E_{kin,1}+E_{kin,2}$ shows a remarkable dip: observe that kinetic energy disappears and comes back again. Ask the students if there is a temporarily violation of the law of conservation of mechanical energy.
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4003 Mortar/1M4003.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4003 Mortar/1M4003.md
index fa0975eb..db9719c1 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4003 Mortar/1M4003.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4003 Mortar/1M4003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1m4003/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1m4003_figure_0
+
.
```
@@ -30,13 +29,12 @@ name: 1m4003/figure_0
## Presentation
-The dimensions of the components are such that when the mortar is assembled, the top of the steel ball is just level with the top of the launching tube (see {numref}`Figure {number} <1m4003/figure_1>`).
+The dimensions of the components are such that when the mortar is assembled, the top of the steel ball is just level with the top of the launching tube (see {numref}`Figure {number} <1m4003_figure_1>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1m4003_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1m4003/figure_1
----
.
```
The launching tube has holes drilled in it at every $\mathrm{cm}$, starting from the top. The steel pin is placed at $1 \mathrm{~cm}$ from the top; the ball and spring are placed into the launching tube from the bottom side. The base is hold by hand and firmly holds the launching tube down (see Diagram). In this situation the spring is compressed $1 \mathrm{~cm}$. By means of your other hand the steel pin is pulled out and the steel ball is launched: it just climbs a couple of centimeters. By repeating the demonstration, a numerical value of the elevation can be given.
@@ -47,7 +45,7 @@ To complete the demonstration the spring is compressed $4 \mathrm{~cm}$ (this ne
## Explanation
1. When the spring is compressed it will have a potential energy of $U_{p}=1 / 2 \mathrm{k} \delta^{2}$. ( $\delta$ is the compression of the spring.) When all this potential energy is transferred to the steel ball, the velocity of the steel ball, when leaving the launching tube, can be determined by $1 / 2 m_{b(a l l)} v_{i}^{2}=1 / 2 k \delta^{2}$. The maximum height reached $\left(h_{m}\right)$ can be determined by $1 / 2 m_{b} v_{i}^{2}=m_{b} g h_{m}$. So, $h_{m}=\frac{k \delta^{2}}{2 m_{b} g}$, showing the fourfold in $h_{m}$ when $\delta$ is doubled.
-2. But also the spring is launched! At the moment of launching the top of the spring has a speed $v_{i}$ (same speed as the steel ball). At that moment the bottom of the spring is still at rest. Every part of the spring has a different speed during the launching process, so in order to determine the kinetic energy of the spring we consider a part ( $\mathrm{dm}$ ) of it (see {numref}`Figure {number} <1m4003/figure_2>`):
+2. But also the spring is launched! At the moment of launching the top of the spring has a speed $v_{i}$ (same speed as the steel ball). At that moment the bottom of the spring is still at rest. Every part of the spring has a different speed during the launching process, so in order to determine the kinetic energy of the spring we consider a part ( $\mathrm{dm}$ ) of it (see {numref}`Figure {number} <1m4003_figure_2>`):
$$d m=\frac{m_{s(\text { pring })}}{l} d y . K_{\text {spring }}=\int_{0}^{l} \frac{1}{2} \frac{m_{s}}{l} v(y)^{2} d y$$
@@ -60,10 +58,9 @@ Then:
$$K_{\text {spring }}=\frac{1}{2} \frac{m_{v}}{l} \frac{v_{i}^{2}}{l^{2}} \int_{0}^{l} y^{2} d y=\frac{1}{6} m_{s} v_{i}^{2}$$
```{figure} figures/figure_2.png
----
-width: 70%
-name: 1m4003/figure_2
----
+:width: 70%
+:label: 1m4003_figure_2
+
.
```
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4004 Galileos Pendulum/1M4004.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4004 Galileos Pendulum/1M4004.md
index 36159a43..fb664016 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4004 Galileos Pendulum/1M4004.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4004 Galileos Pendulum/1M4004.md
@@ -9,11 +9,10 @@ To show a phenomenon that can be explained using "conservation of energy".
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1m4004/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1m4004_figure_0
+
.
```
@@ -29,16 +28,15 @@ The pendulum is connected to the blackboard, hanging a couple of cm's in front o
The pendulum is pulled aside upwards to the $30 \mathrm{~cm}$ line. Before releasing the pendulum, students are asked how far the pendulum will go upward on the other side.
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1m4004/figure_1
----
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1m4004_figure_1
+
.
```
-Then it is released and almost reaches the $30 \mathrm{~cm}$ line on the other side (see {numref}`Figure {number} <1m4004/figure_1>`A). A peg is placed at $50 \mathrm{~cm}$ below the point of suspension, blocking the pendulum's thread when the pendulum is released (we use a piece of chalk holding it there by hand). Again the pendulum is pulled aside upwards to the $30 \mathrm{~cm}$ line. Students are asked how high the pendulum will climb now on the other side when the pendulum is released. After their answers the pendulum is released and climbs almost to the $30 \mathrm{~cm}$ line again (see {numref}`Figure {number} <1m4004/figure_1>`B).
+Then it is released and almost reaches the $30 \mathrm{~cm}$ line on the other side (see {numref}`Figure {number} <1m4004_figure_1>`A). A peg is placed at $50 \mathrm{~cm}$ below the point of suspension, blocking the pendulum's thread when the pendulum is released (we use a piece of chalk holding it there by hand). Again the pendulum is pulled aside upwards to the $30 \mathrm{~cm}$ line. Students are asked how high the pendulum will climb now on the other side when the pendulum is released. After their answers the pendulum is released and climbs almost to the $30 \mathrm{~cm}$ line again (see {numref}`Figure {number} <1m4004_figure_1>`B).
-Then the peg is placed at $70 \mathrm{~cm}$ (or lower). It is clear now that the pendulum released at the $30 \mathrm{~cm}$ line can never reach the same line on the other side, the thread is too short. So, ask the students to predict what will happen to the pendulum now. After their answers the pendulum is released and winds itself around the peg! (see {numref}`Figure {number} <1m4004/figure_1>`C).
+Then the peg is placed at $70 \mathrm{~cm}$ (or lower). It is clear now that the pendulum released at the $30 \mathrm{~cm}$ line can never reach the same line on the other side, the thread is too short. So, ask the students to predict what will happen to the pendulum now. After their answers the pendulum is released and winds itself around the peg! (see {numref}`Figure {number} <1m4004_figure_1>`C).
## Explanation
In this situation (conservative field), total mechanical energy is constant:
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/1M4005.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/1M4005.md
index 3a74f795..9f82020c 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/1M4005.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/1M4005.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 40%
-name: 1m4010/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 40%
+:label: 1m4010_figure_0.png
+
.
```
@@ -42,7 +41,6 @@ So the pendulum bob moves in such a way that $U+K=E=$ constant. On release the b
```{iframe} https://www.youtube.com/watch?v=pUdCmRcEljA
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/qr_images/qrcode_watch_v_pUdCmRcEljA.svg b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/qr_images/qrcode_watch_v_pUdCmRcEljA.svg
new file mode 100644
index 00000000..9d35a332
--- /dev/null
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4005 Pendulum of Death/qr_images/qrcode_watch_v_pUdCmRcEljA.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md
index c9bfd7ee..b9eff7cc 100644
--- a/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md
+++ b/book/book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q2001_figure_0.png
+
.
```
@@ -25,13 +24,12 @@ name: 1q2001/figure_0.png
Two rolls of toilet paper are dropped simultaneously from the same height ( $\approx 2 \mathrm{~m}$ ), one of them while holding on to the paper-end of the roll. This roll hits the floor later than the other.
## Explanation
-When you drop the toilet paper roll while holding on to one end, the roll is momentarily rotating about an axis at the edge of the roll. The angular acceleration $(\alpha)$ of the roll during its fall can be found from $\alpha=\frac{\tau}{I}$, where the net torque is given by $\tau=m g r_{2}$ (see {numref}`Figure {number} <1q2001/figure_1.png>`).
+When you drop the toilet paper roll while holding on to one end, the roll is momentarily rotating about an axis at the edge of the roll. The angular acceleration $(\alpha)$ of the roll during its fall can be found from $\alpha=\frac{\tau}{I}$, where the net torque is given by $\tau=m g r_{2}$ (see {numref}`Figure {number} <1q2001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 50%
+:label: 1q2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 50%
-name: 1q2001/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1001 Bottle Rocket/1N1001.md b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1001 Bottle Rocket/1N1001.md
index 3df54cc0..5b857766 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1001 Bottle Rocket/1N1001.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1001 Bottle Rocket/1N1001.md
@@ -1,3 +1,3 @@
-```{include} /book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
+```{include} ../../../1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1004 Throwing a Basketball/1N1004.md b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1004 Throwing a Basketball/1N1004.md
index 688063ee..8e64faa3 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1004 Throwing a Basketball/1N1004.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1004 Throwing a Basketball/1N1004.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n1004_figure_0.png
+
.
```
@@ -25,21 +24,20 @@ name: 1n1004/figure_0.png
## Presentation
The lines on the basketball make it easy to see if the ball rotates yes or no.
-Throw the basketball and observe that before hitting the ground it does not rotate, but that after rebound it rotates (see {numref}`Figure {number} <1n1004/figure_1.png>`A).
+Throw the basketball and observe that before hitting the ground it does not rotate, but that after rebound it rotates (see {numref}`Figure {number} <1n1004_figure_1.png>`A).
+
+Also can be observed that after rebound the ball moves steeper than when it was in the throw (again: see {numref}`Figure {number} <1n1004_figure_1.png>`A).
-Also can be observed that after rebound the ball moves steeper than when it was in the throw (again: see {numref}`Figure {number} <1n1004/figure_1.png>`A).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n1004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n1004/figure_1.png
----
.
```
## Explanation
-The ball has an impulse $p$, which can be looked at as consisting of a vertical component $p_{\nu}$ and a horizontal component $p_{h}$. When the ball hits the ground, $p_{\nu}$ is reversed (supposing complete elasticity). But $p_{h}$ changes because the friction force $F_{R}$, that acts during a short time ( $\Delta t$ ), reduces the horizontal impulse by an amount of $\Delta \vec{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$. The combination of unchanged $p_{v}$ and changed $p_{h}$ makes that the ball mounts steeper ( {numref}`Figure {number} <1n1004/figure_1.png>`C).
+The ball has an impulse $p$, which can be looked at as consisting of a vertical component $p_{\nu}$ and a horizontal component $p_{h}$. When the ball hits the ground, $p_{\nu}$ is reversed (supposing complete elasticity). But $p_{h}$ changes because the friction force $F_{R}$, that acts during a short time ( $\Delta t$ ), reduces the horizontal impulse by an amount of $\Delta \vec{p}_{h}=\int_{0}^{\Delta t} \vec{F}_{R} d t$. The combination of unchanged $p_{v}$ and changed $p_{h}$ makes that the ball mounts steeper ( {numref}`Figure {number} <1n1004_figure_1.png>`C).
That it rotates as well is due to the torque during contact with the ground, changing its angular momentum by an amount of: $\Delta \vec{L}=\int_{0}^{\Delta t} \vec{r} \times \vec{F} d t$.
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1005 Sliding Ladder/1N1005.md b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1005 Sliding Ladder/1N1005.md
index a77174a1..83937ac8 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1005 Sliding Ladder/1N1005.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N10 Impulse and Thrust/1N1005 Sliding Ladder/1N1005.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n1005/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n1005_figure_0
+
.
```
@@ -29,16 +28,15 @@ The glass of the overhead projector and the cover glass are cleaned and polished
**Presentation**
-The cover glass rests against the wooden block (see {numref}`Figure {number} <1n1005/figure_0>`A). By hand, the inclination of the cover glass is decreased by pulling the wooden block very slowly to the right (see {numref}`Figure {number} <1n1005/figure_0>`B). At a certain moment the cover glass starts sliding: It moves downwards and away from the wooden block. Pose the question to the students: "What makes the cover glass move away from the wooden block?"
+The cover glass rests against the wooden block (see {numref}`Figure {number} <1n1005_figure_0>`A). By hand, the inclination of the cover glass is decreased by pulling the wooden block very slowly to the right (see {numref}`Figure {number} <1n1005_figure_0>`B). At a certain moment the cover glass starts sliding: It moves downwards and away from the wooden block. Pose the question to the students: "What makes the cover glass move away from the wooden block?"
## Explanation
-During the sliding movement, five forces are acting: The weight $G$, the normal forces $N_A$ and $N_B$ and the friction forces in $A$ and $B$ (see {numref}`Figure {number} <1n1005/figure_1>`; the friction forces are neglected).
+During the sliding movement, five forces are acting: The weight $G$, the normal forces $N_A$ and $N_B$ and the friction forces in $A$ and $B$ (see {numref}`Figure {number} <1n1005_figure_1>`; the friction forces are neglected).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n1005_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n1005/figure_1
----
.
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/1N2001.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/1N2001.md
index 6d9242d7..9aad7216 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/1N2001.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/1N2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2001_figure_0.png
+
.
```
@@ -48,21 +47,19 @@ The cart track is carefully leveled (by setting a cart on the track to see which
## Explanation
In explaining the situations demonstrated, a rule introduced by Huygens can be used: *"If in an elastic collision the sum of the impulses equals zero, then both objects reverse and have the same speed after the collision as before the collision."* (CM coordinate system.)
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2001_figure_1.png
+
.
```
-This rule can easily be verified in applying conservation of momentum and conservation of kinetic energy. This method is shown here for situation 1 only, for the other situations the result is shown (see {numref}`Figure {number} <1n2001/figure_1.png>` and {numref}`Figure {number} <1n2001/figure_2.png>`). {numref}`Figure {number} <1n2001/figure_2.png>` shows the observed $-v_{1}$ and $v_{2}$ after the collision.
+This rule can easily be verified in applying conservation of momentum and conservation of kinetic energy. This method is shown here for situation 1 only, for the other situations the result is shown (see {numref}`Figure {number} <1n2001_figure_1.png>` and {numref}`Figure {number} <1n2001_figure_2.png>`). {numref}`Figure {number} <1n2001_figure_2.png>` shows the observed $-v_{1}$ and $v_{2}$ after the collision.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1n2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1n2001_figure_2.png
+
.
```
@@ -70,7 +67,6 @@ name: 1n2001/figure_2.png
```{iframe} https://www.youtube.com/watch?v=vobfBzjQzEo
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/qr_images/qrcode_watch_v_vobfBzjQzEo.svg b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/qr_images/qrcode_watch_v_vobfBzjQzEo.svg
new file mode 100644
index 00000000..149382fa
--- /dev/null
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2001 Elastic Collisions/qr_images/qrcode_watch_v_vobfBzjQzEo.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/1N2002.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/1N2002.md
index d06de52f..735d0605 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/1N2002.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/1N2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2002_figure_0.png
+
.
```
@@ -36,27 +35,24 @@ The cart track is carefully levelled (by setting a cart on the track to see whic
6. As 5, but now with a $3\mathrm{~m}$-cart in the middle. After collision, both carts stick together and hardly move any longer.
## Explanation
- In presentation 1, the total momentum equals zero and remains so after the collision. In presentations 2 to 6, conservation of momentum leads to the diagrams shown in {numref}`Figure {number} <1n2002/figure_1.png>` (before collision) and {numref}`Figure {number} <1n2002/figure_2.png>` (after collision).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2002/figure_1.png
----
+ In presentation 1, the total momentum equals zero and remains so after the collision. In presentations 2 to 6, conservation of momentum leads to the diagrams shown in {numref}`Figure {number} <1n2002_figure_1.png>` (before collision) and {numref}`Figure {number} <1n2002_figure_2.png>` (after collision).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2002_figure_1.png
+
.
```
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1n2002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1n2002_figure_2.png
+
.
```
## Video Rhett Allain
```{iframe} https://www.youtube.com/watch?v=eHI21Sv9z3k
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/qr_images/qrcode_watch_v_eHI21Sv9z3k.svg b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/qr_images/qrcode_watch_v_eHI21Sv9z3k.svg
new file mode 100644
index 00000000..35770f56
--- /dev/null
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2002 Inelastic Collisions/qr_images/qrcode_watch_v_eHI21Sv9z3k.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2004 Colliding Balls/1N2004.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2004 Colliding Balls/1N2004.md
index 93118c5b..ec2a96ea 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2004 Colliding Balls/1N2004.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2004 Colliding Balls/1N2004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2004_figure_0.png
+
.
```
@@ -21,67 +20,53 @@ Elastic balls hanging from a frame ("Newton's cradle")
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/URo-_ozbO18?si=RkoUfOX2rN3n9rqg
+```
The identical balls are bifilarly suspended in a straight row. In horizontal equilibrium the balls are just in contact. Speeds at the time of contact are, to a first approximation, proportional to the horizontal displacement from rest position.
1. *Two balls are suspended.*
-One ball is pulled out and released. It hits the other and this one bounces out to the other side; the first ball being at rest now. (See {numref}`Figure {number} <1n2004/figure_1.png>`.)
+One ball is pulled out and released. It hits the other and this one bounces out to the other side; the first ball being at rest now. (See {numref}`Figure {number} <1n2004_figure_1.png>`.)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2004/figure_1.png
----
.
```
- Both balls are pulled out and released. They hit and both rebounce almost to the original height. (See {numref}`Figure {number} <1n2004/figure_2.png>`.)
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1n2004/figure_2.png
----
+ Both balls are pulled out and released. They hit and both rebounce almost to the original height. (See {numref}`Figure {number} <1n2004_figure_2.png>`.)
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1n2004_figure_2.png
+
.
```
- Both balls are pulled out but one ball more than the other. In this way the two balls will have different speeds. They are released, hit, and it can be observed that after the collision the two balls have interchanged their speeds. (See {numref}`Figure {number} <1n2004/figure_3.png>`.)
+ Both balls are pulled out but one ball more than the other. In this way the two balls will have different speeds. They are released, hit, and it can be observed that after the collision the two balls have interchanged their speeds. (See {numref}`Figure {number} <1n2004_figure_3.png>`.)
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1n2004_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1n2004/figure_3.png
----
.
```
2. *More balls are suspended.*
-When 3 (or 4 , or 5 , etc.) balls are suspended the demonstrations performed with two balls can be repeated. The observed phenomena are similar. The balls between the two outer balls are not taking part in the movements. (See {numref}`Figure {number} <1n2004/figure_4.png>`.)
+When 3 (or 4 , or 5 , etc.) balls are suspended the demonstrations performed with two balls can be repeated. The observed phenomena are similar. The balls between the two outer balls are not taking part in the movements. (See {numref}`Figure {number} <1n2004_figure_4.png>`.)
+
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 1n2004_figure_4.png
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 1n2004/figure_4.png
----
.
```
-When two balls are pulled out and released, they hit the others and two balls bounce out to the other side. With three, three bounce out, etc. It is always the same number of balls. (See {numref}`Figure {number} <1n2004/figure_5.png>`.)
+When two balls are pulled out and released, they hit the others and two balls bounce out to the other side. With three, three bounce out, etc. It is always the same number of balls. (See {numref}`Figure {number} <1n2004_figure_5.png>`.)
+
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 1n2004_figure_5.png
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 1n2004/figure_5.png
----
.
```
3. Two balls of *different mass* ( $m$ and $3 m$ ).
@@ -92,13 +77,12 @@ name: 1n2004/figure_5.png
In all three demonstrations the starting position returns after two collisions.
## Explanation
-{numref}`Figure {number} <1n2004/figure_6.png>` shows the situation before and after an elastic collision. In an elastic collision, both momentum and kinetic energy are conserved. This means that $v_{\text {rel }}$ will not change: $u_{2}-u_{1}=V_{\text {rel }}$
+{numref}`Figure {number} <1n2004_figure_6.png>` shows the situation before and after an elastic collision. In an elastic collision, both momentum and kinetic energy are conserved. This means that $v_{\text {rel }}$ will not change: $u_{2}-u_{1}=V_{\text {rel }}$
+
+```{figure} figures/figure_6.png
+:width: 70%
+:label: 1n2004_figure_6.png
-```{figure} figures/figure_6.png
----
-width: 70%
-name: 1n2004/figure_6.png
----
.
```
@@ -124,9 +108,9 @@ The next table shows the results of different situations concerning our demonstr
This table explains the behavior shown in presentation 1 and 3 .
-In the demonstration of {numref}`Figure {number} <1n2004/figure_4.png>`, $a$ hits $b$. $b$ gets the speed of $a$ (see table) and immediately hits $c$. $b$ comes to rest and $c$ gets the speed of $b$ and immediately hits $d$ etc. At the end, $e$ is launched with the speed $v$ that $a$ originally had.
+In the demonstration of {numref}`Figure {number} <1n2004_figure_4.png>`, $a$ hits $b$. $b$ gets the speed of $a$ (see table) and immediately hits $c$. $b$ comes to rest and $c$ gets the speed of $b$ and immediately hits $d$ etc. At the end, $e$ is launched with the speed $v$ that $a$ originally had.
-In the demonstration of {numref}`Figure {number} <1n2004/figure_5.png>` , the first thing that happens is that $b$ hits $c$. $b$ comes to rest and finally $e$ is launched. In the meantime $a$ hits $b$ and $a$ comes to rest and finally $d$ is launched.
+In the demonstration of {numref}`Figure {number} <1n2004_figure_5.png>` , the first thing that happens is that $b$ hits $c$. $b$ comes to rest and finally $e$ is launched. In the meantime $a$ hits $b$ and $a$ comes to rest and finally $d$ is launched.
If not reasoning step by step, the question could be raised why ball $e$ is not coming out with double velocity. After all this would conserve momentum. But checking kinetic energy will show that in that case kinetic energy is not conserved.
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2005 Demonstrator and Cart/1N2005.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2005 Demonstrator and Cart/1N2005.md
index d4dc4682..e5c1d6f0 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2005 Demonstrator and Cart/1N2005.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2005 Demonstrator and Cart/1N2005.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2005_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2006 Knock Out/1N2006.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2006 Knock Out/1N2006.md
index d6ffcf95..fdbcbec5 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2006 Knock Out/1N2006.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2006 Knock Out/1N2006.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2006_figure_0.png
+
.
```
@@ -39,13 +38,12 @@ One ball is given a deflection by pressing it to the support-rod. With your othe
When the ball hits the wooden block, the block experiences a force depending on the momentum $\int Fdt$. The elastic collision imparts more momentum to the block because the ball changes its momentum from $+mv$ to $-mv$ (a change of $-2mv$), while the ball hitting the clayed block changes its momentum from $+mv$ to $0$ (a change of $-mv$). So $\int Fdt$ is twice as high in the first situation.
## Remarks
-* Sticking the piece of clay to the wooden block, we model it in a sharp way (see {numref}`Figure {number} <1n2006/figure_1.png>`).
+* Sticking the piece of clay to the wooden block, we model it in a sharp way (see {numref}`Figure {number} <1n2006_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2006_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2006/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2007 Pulling a Slackened Rope/1N2007.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2007 Pulling a Slackened Rope/1N2007.md
index c8449245..345d88b1 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2007 Pulling a Slackened Rope/1N2007.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2007 Pulling a Slackened Rope/1N2007.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2007_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2008 Spinning Bouncing Ball/1N2008.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2008 Spinning Bouncing Ball/1N2008.md
index 6940bd81..1c50524b 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2008 Spinning Bouncing Ball/1N2008.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2008 Spinning Bouncing Ball/1N2008.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1n2008/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1n2008_figure_0.png
+
.
```
@@ -27,12 +26,11 @@ name: 1n2008/figure_0.png
## Presentation
- The racquetball is dropped straight down from your hand and bounces back (see drawing A in Diagram). This is a well known phenomenon. The laws of mechanics explain the reversal of the velocity (see {numref}`Figure {number} <1n2008/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1n2008/figure_1.png
----
+ The racquetball is dropped straight down from your hand and bounces back (see drawing A in Diagram). This is a well known phenomenon. The laws of mechanics explain the reversal of the velocity (see {numref}`Figure {number} <1n2008_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1n2008_figure_1.png
+
.
```
There is a strong correspondence between the formalisms of translational and rotational mechanics. Awareness of this correspondence leads us to the prediction that when the bouncing ball is spinning in one direction when dropped, it has to spin in the opposite direction after bouncing! (see drawing B in Diagram.)
@@ -40,13 +38,12 @@ There is a strong correspondence between the formalisms of translational and rot
We try this and it really works that way! (The camera looks down on the bouncing ball and "sees" the label on the ball rotate in one direction and after bouncing in the other direction, and so on, while bouncing.)
## Explanation
-{numref}`Figure {number} <1n2008/figure_2.png>` shows the explanation from a point of view of rotational dynamics. In order to perform this demonstration you really need a racquetball.
+{numref}`Figure {number} <1n2008_figure_2.png>` shows the explanation from a point of view of rotational dynamics. In order to perform this demonstration you really need a racquetball.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1n2008_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1n2008/figure_2.png
----
.
```
When, for instance, you use a superball, the ball continues to rotate in the same direction after bouncing. In order to get a reversal of the sense of rotation it is wise to study again the correspondence between translational and rotational laws:
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2009 Super Balls Double Ball Drop/1N2009.md b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2009 Super Balls Double Ball Drop/1N2009.md
index 5aaaf74e..969c3b51 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2009 Super Balls Double Ball Drop/1N2009.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N20 Conserv/1N2009 Super Balls Double Ball Drop/1N2009.md
@@ -1,3 +1,3 @@
-```{include} /book/1 mechanics/1E relative motion/1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md
+```{include} ../../../1E10 Mov Ref/1E1001 Super Balls Double Ball Drop/1E1001.md
```
diff --git a/book/book/1 mechanics/1N lin momentum and collisions/1N22 Rockets/1N2201 Bottle Rocket/1N2201.md b/book/book/1 mechanics/1N lin momentum and collisions/1N22 Rockets/1N2201 Bottle Rocket/1N2201.md
index 3df54cc0..5b857766 100644
--- a/book/book/1 mechanics/1N lin momentum and collisions/1N22 Rockets/1N2201 Bottle Rocket/1N2201.md
+++ b/book/book/1 mechanics/1N lin momentum and collisions/1N22 Rockets/1N2201 Bottle Rocket/1N2201.md
@@ -1,3 +1,3 @@
-```{include} /book/1 mechanics/1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
+```{include} ../../../1H newton 3/1H10 Act and React/1H1004 Bottle Rocket/1H1004.md
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1001 Bicycle Wheel Pendulum/1Q1001.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1001 Bicycle Wheel Pendulum/1Q1001.md
index 1e62aad6..09db1a03 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1001 Bicycle Wheel Pendulum/1Q1001.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1001 Bicycle Wheel Pendulum/1Q1001.md
@@ -8,11 +8,10 @@ A qualitative demonstration of the parallel axis theorem.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1001_figure_0
+
.
```
@@ -22,13 +21,12 @@ name: 1q1001/figure_0
* Large frame to suspend the bracket and bicycle wheel.
## Presentation
-The wheel is free to rotate about its axis. Then the wheel is swung as a pendulum. The period of oscillation is noted. (It can also be shown that the period is independent of the speed of rotation of the wheel.) Now the wheel is fixed by turning the nuts in the bracket holding the wheel rim (see {numref}`Figure {number} <1q1001/figure_1>`).
+The wheel is free to rotate about its axis. Then the wheel is swung as a pendulum. The period of oscillation is noted. (It can also be shown that the period is independent of the speed of rotation of the wheel.) Now the wheel is fixed by turning the nuts in the bracket holding the wheel rim (see {numref}`Figure {number} <1q1001_figure_1>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q1001_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q1001/figure_1
----
.
```
Again the apparatus is swung as a pendulum. The period observed is longer than that in the previous case.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/1Q1002.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/1Q1002.md
index cde348ce..273d1b3b 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/1Q1002.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/1Q1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1002_figure_0.png
+
.
```
@@ -25,17 +24,8 @@ name: 1q1002/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/bFp8MVOZZ5U?si=tIfsC0bIuZWWaZXQ
+```
Pendulum 1 and 2 are swinging. It can be observed that they have the same period. Pendulum 1 and 3 are swinging. Again the same period is observed.
@@ -46,24 +36,22 @@ For a physical pendulum the period $T$ is given by: $T=\frac{2 \pi}{\sqrt{g}} \s
Also, $I_{A}=I_{C}+m s^{2}$ (Steiner), so $T$ is constant as long as $s$ is constant.
-The suspension of the three pendulums is chosen such that the distance $s$ is always the same because they are situated on a circle through $\mathrm{C}$ (see {numref}`Figure {number} <1q1002/figure_1.png>`). $s=50 \mathrm{~cm}$.
+The suspension of the three pendulums is chosen such that the distance $s$ is always the same because they are situated on a circle through $\mathrm{C}$ (see {numref}`Figure {number} <1q1002_figure_1.png>`). $s=50 \mathrm{~cm}$.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q1002/figure_1.png
----
.
```
## Remarks
-We also have a suspension as shown in {numref}`Figure {number} <1q1002/figure_2.png>`. Now the suspension point is $0.167 \mathrm{~m}$ away from $\mathrm{C}$ and again $\mathrm{T}$ is the same because now the pendulum swings through the point of its reduced length (see demonstration "Physical pendulum (1)").
+We also have a suspension as shown in {numref}`Figure {number} <1q1002_figure_2.png>`. Now the suspension point is $0.167 \mathrm{~m}$ away from $\mathrm{C}$ and again $\mathrm{T}$ is the same because now the pendulum swings through the point of its reduced length (see demonstration "Physical pendulum (1)").
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q1002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q1002_figure_2.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/qr_images/qrcode_bFp8MVOZZ5U_si_tIfsC0bIuZWWaZXQ_.svg b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/qr_images/qrcode_bFp8MVOZZ5U_si_tIfsC0bIuZWWaZXQ_.svg
new file mode 100644
index 00000000..132cc0fe
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1002 Physical Pendulum/qr_images/qrcode_bFp8MVOZZ5U_si_tIfsC0bIuZWWaZXQ_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1003 Maximum Rotational Inertia/1Q1003.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1003 Maximum Rotational Inertia/1Q1003.md
index 31f2cc60..01cca08a 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1003 Maximum Rotational Inertia/1Q1003.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1003 Maximum Rotational Inertia/1Q1003.md
@@ -9,11 +9,10 @@ To show that an object prefers to rotate around an axis with largest moment of i
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1003_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ A rope suspended in the drills head will climb very fast to a rotation in a hori
When a chain is used, this chain will also finally rotate in a horizontal plane, but it takes much more time to go from the vertical suspension to the horizontal rotation. (Now a study of the sequence in between is possible.)
-{numref}`Figure {number} <1q1003/figure_1.png>` shows several objects that can be used in this demonstration.
+{numref}`Figure {number} <1q1003_figure_1.png>` shows several objects that can be used in this demonstration.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q1003/figure_1.png
----
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1004 Rolling Down a Wide Gutter/1Q1004.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1004 Rolling Down a Wide Gutter/1Q1004.md
index 374d328d..33a6f487 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1004 Rolling Down a Wide Gutter/1Q1004.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1004 Rolling Down a Wide Gutter/1Q1004.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1004_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/1Q1005.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/1Q1005.md
index 2c889ec8..a4c59015 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/1Q1005.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/1Q1005.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1005_figure_0.png
+
.
```
@@ -25,17 +24,8 @@ name: 1q1005/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/TpvL20gy_bQ?si=E_omtbgGepdnpCPd
+```
The presentator sits on the swivel chair, holding in each hand a $1 \mathrm{~kg}$ mass. His hands rest in his lap. He is given angular speed by an assistant. While rotating, he extends his arms. Clearly can be observed that his angular velocity reduces. Returning his hands to his lap will increase the angular velocity again.
@@ -52,7 +42,6 @@ An extra demostration of the same principle as in the demonstration.
```{iframe} https://www.youtube.com/watch?v=jRYAl-mSibs
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/qr_images/qrcode_watch_v_jRYAl_mSibs.svg b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/qr_images/qrcode_watch_v_jRYAl_mSibs.svg
new file mode 100644
index 00000000..44d81d29
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1005 Pirouette/qr_images/qrcode_watch_v_jRYAl_mSibs.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/1Q1006.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/1Q1006.md
index 748201da..0f3e9c4c 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/1Q1006.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/1Q1006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1006/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1006_figure_0
+
.
```
@@ -40,49 +39,22 @@ The ramp has to be adjusted horizontally in its cross direction, using an air-le
### Presentation.
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/gkH8Ex7yCb0?si=QKnOiUn7372H9vz_
+```
Different races are presented to the students. Before each race, the mass of the racing objects is determined by placing each object on the balance. Then students are asked to predict the result of that race: Is there a winner/loser? When the answer is yes, which object will be the winner/loser?
- Race 1:
$m_{1}, m_{2}$ and $m_{3}$ race down the ramp together, starting at the same time. $m_{1}$ is the winner, $m_{3}$ the loser. (Most students predict the right answer. Evidently the distribution of mass is important.)
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/Sm8McbLyKos?si=2Gz-ywm19zM4dUl6
+```
- Race 2:
$m_{2}$ and $m_{4}$ race down the ramp together. There is no winner. (Most students predict the wrong answer. Evidently mass is not important in this demonstration. It makes me remember Galileo dropping objects from the tower of Pisa, in which experiment mass has also no influence on the downward acceleration.)
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/0m_dNR5KPuU?si=S715TrB2Vlc-zVdl
+```
- Race 3:
$m_{2}$, $m_{4}$ and $m_{5}$ race down the ramp together. They arrive together; there is no winner. (Many students don't dare to predict. Evidently radius $R$ is of no importance in this experiment.)
@@ -92,13 +64,12 @@ Now an overhead sheet is presented to the students that shows a table of the exp
- Race 4:
$m_{2}, m_{6}$ and $m_{7} . m_{6}$ is the winner, $m_{7}$ the loser.
-{numref}`Figure {number} <1q1006/figure_1>` shows a summary. '
+{numref}`Figure {number} <1q1006_figure_1>` shows a summary. '
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q1006_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q1006/figure_1
----
.
```
@@ -109,7 +80,7 @@ Conservation of energy tells us: $1 / 2 m v_{c}^{2}+1 / 2 I \omega^{2}+m g h=$ c
By $v_{c}=\omega R, h=s \sin \gamma$ and differentiating, we find $a_{c}=\frac{g \sin \gamma}{1+\frac{I_{c}}{m R^{2}}}$
-The moment of inertia of objects with circular symmetry can be written as: $I=C m R^{2}$, where $C$ is a constant. From tables we know (see {numref}`Figure {number} <1q1006/figure_1>`):
+The moment of inertia of objects with circular symmetry can be written as: $I=C m R^{2}$, where $C$ is a constant. From tables we know (see {numref}`Figure {number} <1q1006_figure_1>`):
- solid sphere, $C=2 / 5$
- solid cilinder, $C=1 / 2$
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/qr_images/qrcode_gkH8Ex7yCb0_si_QKnOiUn7372H9vz__.svg b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/qr_images/qrcode_gkH8Ex7yCb0_si_QKnOiUn7372H9vz__.svg
new file mode 100644
index 00000000..e6a5fb4a
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1006 Rolling Downhill/qr_images/qrcode_gkH8Ex7yCb0_si_QKnOiUn7372H9vz__.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1007 Matchbox and Wineglass/1Q1007.md b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1007 Matchbox and Wineglass/1Q1007.md
index cb936b40..4bfde3f5 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1007 Matchbox and Wineglass/1Q1007.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q10 Momentum of Inertia/1Q1007 Matchbox and Wineglass/1Q1007.md
@@ -9,11 +9,10 @@ To show an example in which conservation of angular momentum explains the trick.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q1007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q1007_figure_0.png
+
.
```
@@ -24,17 +23,8 @@ name: 1q1007/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/x24R0ZDXmJU?si=KInmmw8Qho4arsZ_
+```
See Diagram. The wineglass hangs straight down a few centimeters below the pencil, the matchbox is held so that its string is nearly horizontal. Now release the matchbox and ... the wineglass will not hit the floor!
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2001 Dropping Rolls of Toilet Paper/1Q2001.md b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2001 Dropping Rolls of Toilet Paper/1Q2001.md
index 996ef465..631e7181 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2001 Dropping Rolls of Toilet Paper/1Q2001.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2001 Dropping Rolls of Toilet Paper/1Q2001.md
@@ -1,5 +1,5 @@
-```{include} /book/1 mechanics/1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md
+```{include} ../../../1M work and energy/1M40 Conserv of Energy/1M4006 Dropping Rolls of Toilet Paper/1M4006.md
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2002 Yo-Yo/1Q2002.md b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2002 Yo-Yo/1Q2002.md
index 658d9b0b..e889cd44 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2002 Yo-Yo/1Q2002.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2002 Yo-Yo/1Q2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q2002_figure_0.png
+
.
```
@@ -28,19 +27,18 @@ name: 1q2002/figure_0.png
## Presentation
We all know the yo-yo: Two circular discs with a common shaft and a string several times wrapped around it. Hold the end of the string stationary and release the yo-yo. The string unwinds as the yo-yo drops and rotates with increasing speed. When the unwrapping is completed, the yo-yo climbs again, comes to a stop and starts over again. etc.
-Suspending the yo-yo to a force sensor, a registration of the tension in the string is made (red graph in {numref}`Figure {number} <1q2002/figure_1.png>` left). When, finally, the yo-yo has come to rest, such a registration is repeated (green line in {numref}`Figure {number} <1q2002/figure_1.png>` left).
+Suspending the yo-yo to a force sensor, a registration of the tension in the string is made (red graph in {numref}`Figure {number} <1q2002_figure_1.png>` left). When, finally, the yo-yo has come to rest, such a registration is repeated (green line in {numref}`Figure {number} <1q2002_figure_1.png>` left).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q2002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q2002/figure_1.png
----
.
```
When studying these graphs, the jerk at the turning point is clearly observed. (Also a strong vibration.) See that the jerk at the turning point is much higher than the weight of the yo-yo.
-Going from one jerk to the next, the highest position of the yo-yo is halfway between the two jerks. When a complete cycle is enlarged (see {numref}`Figure {number} <1q2002/figure_1.png>` right), it is clear that during the complete cycle the string tension is lower than the weight of the yo-yo.
+Going from one jerk to the next, the highest position of the yo-yo is halfway between the two jerks. When a complete cycle is enlarged (see {numref}`Figure {number} <1q2002_figure_1.png>` right), it is clear that during the complete cycle the string tension is lower than the weight of the yo-yo.
## Explanation
The yo-yo accelerates (a) due to a force $m a=m g-F_{s}\left(F_{s}\right.$ being the string tension and $m$ the mass of the yo-yo.)
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2003 Maxwheel/1Q2003.md b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2003 Maxwheel/1Q2003.md
index a5bdd97c..8f5ff283 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2003 Maxwheel/1Q2003.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q20 Rot Energy/1Q2003 Maxwheel/1Q2003.md
@@ -12,11 +12,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q2003_figure_0.png
+
.
```
@@ -33,15 +32,14 @@ The wheel is rolled by hand to its uppermost position. When released, the wheel
Going through its lowest position, a strong jerk can be observed.
-Using a motionsensor, placed under the wheel (see Diagram), the position of the wheel can be measured continuously using a data-acquisition system. Such a system enables to calculate velocity and acceleration and display these variables graphically while the wheel is running up and down (see {numref}`Figure {number} <1q2003/figure_1.png>`). After a couple of periods data-acquisition is stopped and the results can be discussed:
+Using a motionsensor, placed under the wheel (see Diagram), the position of the wheel can be measured continuously using a data-acquisition system. Such a system enables to calculate velocity and acceleration and display these variables graphically while the wheel is running up and down (see {numref}`Figure {number} <1q2003_figure_1.png>`). After a couple of periods data-acquisition is stopped and the results can be discussed:
+
+From the position-graph (see {numref}`Figure {number} <1q2003_figure_1.png>`) we read $\Delta h=0.7 m$, giving that $E_{\text {pot }}$ changes an amount $\Delta E_{\text {pot }}=m g \Delta h=m g \cdot 0 .7$, so around $7 \mathrm{~m}[\mathrm{~J}]$.
-From the position-graph (see {numref}`Figure {number} <1q2003/figure_1.png>`) we read $\Delta h=0.7 m$, giving that $E_{\text {pot }}$ changes an amount $\Delta E_{\text {pot }}=m g \Delta h=m g \cdot 0 .7$, so around $7 \mathrm{~m}[\mathrm{~J}]$.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q2003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q2003/figure_1.png
----
.
```
@@ -58,11 +56,10 @@ $\Delta E_{\text {pot }}=E_{\text {trans }}+E_{\text {rot }}$, so
$m g h=\frac{1}{2} m v^{2}+\frac{1}{2} I \omega^{2}$, with $\omega=\frac{v}{r_{1}}$ and $I=m\left(R^{2}+r_{1}^{2}\right)$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q2003/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q2003_figure_2.png
+
.
```
We find:
@@ -85,7 +82,7 @@ Passing through its lowest point, the wheel changes its momentum from $-m v$ to
## Remarks
-- Care must be exercised so that the two threads always have the same length and so there is no overlapping on the spindle which would change $r_{1}$. In our wheel, overlapping is prevented by giving different lengths to the spindle and suspension bar (see {numref}`Figure {number} <1q2003/figure_2.png>`B).
+- Care must be exercised so that the two threads always have the same length and so there is no overlapping on the spindle which would change $r_{1}$. In our wheel, overlapping is prevented by giving different lengths to the spindle and suspension bar (see {numref}`Figure {number} <1q2003_figure_2.png>`B).
- When measuring $r_{1}$ do not forget the thickness of the thread!
- As an introduction to this experiment see the demonstration "Yo-yo" in this database. Doing so, the measured acceleration can be related to the force of the strings holding the wheel.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4002 Colliding Magnets/1Q4002.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4002 Colliding Magnets/1Q4002.md
index 5b5a9cb1..d41f6a00 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4002 Colliding Magnets/1Q4002.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4002 Colliding Magnets/1Q4002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4002_figure_0.png
+
.
```
@@ -21,13 +20,12 @@ name: 1q4002/figure_0.png
## Presentation
- Slide across the table (or floor) one ring towards the other to make a glancing collision. The two magnets stick together and rotate about their common center of mass (see {numref}`Figure {number} <1q4002/figure_1.png>`). (No rotation is observed for head-on collisions.)
+ Slide across the table (or floor) one ring towards the other to make a glancing collision. The two magnets stick together and rotate about their common center of mass (see {numref}`Figure {number} <1q4002_figure_1.png>`). (No rotation is observed for head-on collisions.)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4002/figure_1.png
----
.
```
@@ -38,7 +36,7 @@ In the beginning there is no rotation, so the question to the students is: "From
## Remarks
* Because the magnet is fired by hand, some practice is needed to make nice glancing collisions.
- * We have taped the sides of the magnets in order to prevent damage when the magnets collide. (See {numref}`Figure {number} <1q4002/figure_1.png>`)
+ * We have taped the sides of the magnets in order to prevent damage when the magnets collide. (See {numref}`Figure {number} <1q4002_figure_1.png>`)
## Sources
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4004 Sweet Spot/1Q4004.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4004 Sweet Spot/1Q4004.md
index cac60c05..2e37e315 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4004 Sweet Spot/1Q4004.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4004 Sweet Spot/1Q4004.md
@@ -9,30 +9,28 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4004_figure_0.png
+
.
```
## Equipment
- $2.2 \mathrm{~m}$ track (PASCO-ME9452) with end stop.
-- Plunger cart (PASCO-ME9430), $m=.51 \mathrm{~kg}$. The plunger is connected to a compression spring (see {numref}`Figure {number} <1q4004/figure_2.png>`)
+- Plunger cart (PASCO-ME9430), $m=.51 \mathrm{~kg}$. The plunger is connected to a compression spring (see {numref}`Figure {number} <1q4004_figure_2.png>`)
- Meterstick, pertinax, $m=.42 \mathrm{~kg}$.
- Meterstick, aluminum, $m=1.64 \mathrm{~kg}$.
-- Clamping material to fix metersticks as pendulums and to limit its initial amplitude (see detail in {numref}`Figure {number} <1q4004/figure_1.png>`).
+- Clamping material to fix metersticks as pendulums and to limit its initial amplitude (see detail in {numref}`Figure {number} <1q4004_figure_1.png>`).
- 4 wooden markers, triangular shaped.
## Presentation
-In the demonstration [Percussionpoint](../../1Q60%20Rot%20Stability/1Q6005%20Percussionpoint/1Q6005.md) it is shown to the students that a ball hitting a baseball bat will cause no impulse to your hands when you hold the bat at the percussion point. While presenting this demonstration, students often ask if this situation is also the "best" point for hitting the ball, meaning: where do we need to hit the ball to transfer maximum kinetic energy to it. Demonstration will show that this so-called "sweet spot" is not the same as the one related to the percussion point. Set up the demonstration as shown in the Diagram. The meterstick-pendulum has a limited amplitude thanks to a little bar functioning as a stop (see {numref}`Figure {number} <1q4004/figure_1.png>`). Clamp A and B shown in this figure can be used to shift the complete pendulum-system up and down. This makes it possible to choose where the meterstick-pendulum will hit the plunger cart.
+In the demonstration [Percussionpoint](../../1Q60%20Rot%20Stability/1Q6005%20Percussionpoint/1Q6005.md) it is shown to the students that a ball hitting a baseball bat will cause no impulse to your hands when you hold the bat at the percussion point. While presenting this demonstration, students often ask if this situation is also the "best" point for hitting the ball, meaning: where do we need to hit the ball to transfer maximum kinetic energy to it. Demonstration will show that this so-called "sweet spot" is not the same as the one related to the percussion point. Set up the demonstration as shown in the Diagram. The meterstick-pendulum has a limited amplitude thanks to a little bar functioning as a stop (see {numref}`Figure {number} <1q4004_figure_1.png>`). Clamp A and B shown in this figure can be used to shift the complete pendulum-system up and down. This makes it possible to choose where the meterstick-pendulum will hit the plunger cart.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4004/figure_1.png
----
.
```
First we use the pertinax meterstick. The stick hits the plunger of the cart at around $25 \mathrm{~cm}$ distance from its point of suspension. After the collision, the cart moves along the track and stops at point 1 (see Diagram). This distance is a measure for the amount of kinetic energy the cart got initially at launching. A marker is placed at this point. The procedure is repeated for the stick hitting at 50,67 (corresponding to the percussion point) and $100 \mathrm{~cm}$. The markers 2, 3 and 4 in the Diagram show the respective distances traveled by the cart. Clearly, the second situation imparts most kinetic energy to the cart, and not the one hitting at the percussion point (marker 3 ). The sequence is repeated, but now also the movement of the meterstick after collision is observed. Students will observe that at $25 \mathrm{~cm}$, the meterstick continues swinging in the same direction after the collision, while at $100 \mathrm{~cm}$ the meterstick bounces back. Asking what will happen at around $50 \mathrm{~cm}$ will make them easily predict that the meterstick will stand still after the collision. Next this can be verified.
@@ -40,15 +38,14 @@ First we use the pertinax meterstick. The stick hits the plunger of the cart at
The whole experiment can be repeated with the heavier aluminum stick. This will show a sweet spot at the end of the stick $(100 \mathrm{~cm})$.
## Explanation
- See {numref}`Figure {number} <1q4004/figure_2.png>`.
+ See {numref}`Figure {number} <1q4004_figure_2.png>`.
Supposing that the collision is completely elastic, we apply conservation of angular momentum and conservation of energy.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4004/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4004_figure_2.png
+
.
```
Conservation of angular momentum: $\frac{1}{3} m_{l} l v_{l}=\frac{1}{3} m_{l} l v_{l}^{'}+m_{c} r v_{c}$ ( $v^{'}$ being the velocity of the meterstick after collision)
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4005 Balls on a Rotating Ramp/1Q4005.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4005 Balls on a Rotating Ramp/1Q4005.md
index 80a25c42..87c0c772 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4005 Balls on a Rotating Ramp/1Q4005.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4005 Balls on a Rotating Ramp/1Q4005.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4005_figure_0.png
+
.
```
@@ -47,17 +46,16 @@ The three balls and the track form a system. If there is no external torque on t
Since $L=/ \omega=$ constant, we see that $\omega$ depends on $/$. A change in $\omega$ is given by a change in I: $d \omega=-\frac{L}{I^{2}} d I$. This shows that the largest change in $\omega$ is obtained at low $/$-values. This is when a descending ball approaches the axis of rotation. So, the largest angular acceleration is obtained in the end of the run down the ramp. This also explains why the last ball causes the largest change in $\omega$, since / then approaches its lowest value.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4005/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4005_figure_1.png
+
.
```
### Acceleration along the ramp:
-The centrifugal force $\left(F_{C}\right.$ ) acting on the ball is given by $F_{C}=m R \omega^{2}$ ( $R$ being the perpendicular distance from the axis of rotation to the center of the ball). The force on the ball along the ramp is $F_{r}=m g \sin \theta-\cos \theta$ (see {numref}`Figure {number} <1q4005/figure_1.png>`). So:
+The centrifugal force $\left(F_{C}\right.$ ) acting on the ball is given by $F_{C}=m R \omega^{2}$ ( $R$ being the perpendicular distance from the axis of rotation to the center of the ball). The force on the ball along the ramp is $F_{r}=m g \sin \theta-\cos \theta$ (see {numref}`Figure {number} <1q4005_figure_1.png>`). So:
$F_{r}=k-m R \omega^{2} \cos \theta$. When rolling down, $R$ reduces, but at the same time $\omega$ increases: $L=I \omega=$ constant; $I=m R^{2}$, so: $m R^{2} \omega=L, \omega=\frac{L}{m R^{2}}$. This gives for $F_{r}$ :
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4006 Counter Rotating Disks/1Q4006.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4006 Counter Rotating Disks/1Q4006.md
index 55604b50..f62f61d5 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4006 Counter Rotating Disks/1Q4006.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4006 Counter Rotating Disks/1Q4006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4006_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4007 Dumb Bell/1Q4007.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4007 Dumb Bell/1Q4007.md
index 029f5843..8bc803b0 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4007 Dumb Bell/1Q4007.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4007 Dumb Bell/1Q4007.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4007_figure_0.png
+
.
```
@@ -23,27 +22,25 @@ name: 1q4007/figure_0.png
## Presentation
-The dumbbell is placed on top of the support. A thread is fixed to the center of mass and thrown over the top of the frame and hold slack, away from the dumbbell. The dumbbell is given a rotation by hand. Make the students observe that the two masses of the rotating dumbbell describe two horizontal circles ({numref}`Figure {number} <1q4007/figure_1.png>`a).
+The dumbbell is placed on top of the support. A thread is fixed to the center of mass and thrown over the top of the frame and hold slack, away from the dumbbell. The dumbbell is given a rotation by hand. Make the students observe that the two masses of the rotating dumbbell describe two horizontal circles ({numref}`Figure {number} <1q4007_figure_1.png>`a).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4007_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4007/figure_1.png
----
.
```
-Lift the dumbbell from its support. Almost immediately it can be seen that now the rotation of the dumbbell takes place in one slanting plane ({numref}`Figure {number} <1q4007/figure_1.png>`b).
+Lift the dumbbell from its support. Almost immediately it can be seen that now the rotation of the dumbbell takes place in one slanting plane ({numref}`Figure {number} <1q4007_figure_1.png>`b).
Before lift-off it can be seen that while the dumbbell rotates, the vertical support shaft oscillates/shakes/wobbles strongly and yet it is a thick and strong steel shaft!
## Explanation
-The dumbbell-shaped object rotates about a non-symmetry axis through the center of mass O. {numref}`Figure {number} <1q4007/figure_2.png>`a shows the angular momentum vector of the rotating dumbbell relative to $\mathrm{O}$ at the instant drawn and while the dumbbell rotates the angular momentum vector describes a cone. So the angular momentum changes direction continuously. To do this a torque is needed. The ballbearing support at O gives that torque: A centripetal force $F_{c}$ is needed to move $m$ around in a circle (see {numref}`Figure {number} <1q4007/figure_2.png>`b). This needs a torque $\vec{F}_{c} \times \vec{r}$. (Also $\vec{M}=\frac{d \vec{L}}{d t}$ gives this result.)
+The dumbbell-shaped object rotates about a non-symmetry axis through the center of mass O. {numref}`Figure {number} <1q4007_figure_2.png>`a shows the angular momentum vector of the rotating dumbbell relative to $\mathrm{O}$ at the instant drawn and while the dumbbell rotates the angular momentum vector describes a cone. So the angular momentum changes direction continuously. To do this a torque is needed. The ballbearing support at O gives that torque: A centripetal force $F_{c}$ is needed to move $m$ around in a circle (see {numref}`Figure {number} <1q4007_figure_2.png>`b). This needs a torque $\vec{F}_{c} \times \vec{r}$. (Also $\vec{M}=\frac{d \vec{L}}{d t}$ gives this result.)
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4007_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4007/figure_2.png
----
.
```
This torque also makes the support shaft wobble. The dumbbell needs to rotate in such a way as the direction of $\vec{L}$ dictates at the moment of lift-off.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4008 How an Astronaut can Turn Around in Free Space/1Q4008.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4008 How an Astronaut can Turn Around in Free Space/1Q4008.md
index 9061d66a..711963df 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4008 How an Astronaut can Turn Around in Free Space/1Q4008.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4008 How an Astronaut can Turn Around in Free Space/1Q4008.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4008/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4008_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4009 Playing Tennis/1Q4009.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4009 Playing Tennis/1Q4009.md
index 935edb92..029644ee 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4009 Playing Tennis/1Q4009.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4009 Playing Tennis/1Q4009.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4009/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4009_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4011 Pulling the Rug/1Q4011.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4011 Pulling the Rug/1Q4011.md
index ecf117e8..c8d262d4 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4011 Pulling the Rug/1Q4011.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4011 Pulling the Rug/1Q4011.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4011/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4011_figure_0.png
+
.
```
@@ -33,30 +32,28 @@ name: 1q4011/figure_0.png
The sheet of paper is pulled horizontally out from under the tube. The observed movement of the tube is puzzling to the students, so the demonstration has to be repeated in order to make them describe exactly what they see:
- At first the tube is at rest.
- - Pulling the sheet to the right makes the tube turn counter clockwise and there is a translation to the right (see {numref}`Figure {number} <1q4011/figure_1.png>`).
+ - Pulling the sheet to the right makes the tube turn counter clockwise and there is a translation to the right (see {numref}`Figure {number} <1q4011_figure_1.png>`).
- When the sheet leaves from under the tube, immediately the tube stops its rotation and translation!
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4011/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4011_figure_1.png
+
.
```
- When a tube and a solid cylinder are placed side by side on the sheet of paper the distances traveled in the direction of the pull will differ from each other: the tube will travel farther than the solid cylinder!
## Explanation
-- When the sheet is pulled to the right, the tube wants to stay where it is due to its inertia. But due to friction the tube will slide along with the sheet. Seen from a point on the table this means a clockwise rotation. Yet, there is no torque applied to the tube, since the sheet is very thin! The only way not to violate conservation of angular momentum (which is zero all the time during this demonstration) means that the tube itself has to turn counter clockwise (see {numref}`Figure {number} <1q4011/figure_1.png>`).
+- When the sheet is pulled to the right, the tube wants to stay where it is due to its inertia. But due to friction the tube will slide along with the sheet. Seen from a point on the table this means a clockwise rotation. Yet, there is no torque applied to the tube, since the sheet is very thin! The only way not to violate conservation of angular momentum (which is zero all the time during this demonstration) means that the tube itself has to turn counter clockwise (see {numref}`Figure {number} <1q4011_figure_1.png>`).
- The angular momentum due to the translation of the centre of mass of the object and due to the rotation of the object about its centre of mass must be equal in magnitude and opposite in direction.
- When the tube leaves the sheet the only way for the tube to continue moving would mean that the two components of angular momentum should have the same direction. Since the net angular momentum is zero, movement is not possible any longer.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4011/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4011_figure_2.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4012 Tippe Top/1Q4012.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4012 Tippe Top/1Q4012.md
index 3b2ecbe9..640c708a 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4012 Tippe Top/1Q4012.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4012 Tippe Top/1Q4012.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4012/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4012_figure_0.png
+
.
```
@@ -38,12 +37,11 @@ name: 1q4012/figure_0.png
## Explanation
-The top consists of a hollow sphere that is sliced off with a stem attached to it. This top is in stable static equilibrium when it points its stem upward, so the centre of mass (CM) is below the centre of curvature (C). This top is given a spin $\omega_{0}$ (see {numref}`Figure {number} <1q4012/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4012/figure_1.png
----
+The top consists of a hollow sphere that is sliced off with a stem attached to it. This top is in stable static equilibrium when it points its stem upward, so the centre of mass (CM) is below the centre of curvature (C). This top is given a spin $\omega_{0}$ (see {numref}`Figure {number} <1q4012_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4012_figure_1.png
+
.
```
Now the tippe top has an amount of angular momentum $\left(L_{0}\right)$. The demonstrations with tippe top nr. 2 , nr. 3 and nr. 1 on the painted board, show that this vertical angular momentum remains predominantly in that direction during the entire inversion process: $L_{0}$ keeps during this demonstration the same direction. (Thus the direction of rotation of the tippe top with respect to the coordinates fixed in its body is reversed.)
@@ -52,20 +50,18 @@ During inversion the centre of mass of the tippe top is elevated; it follows tha
A complete analysis to account for the behavior of the top is quite elaborate (see Sources). Next a simplified explanation is attempted:
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4012/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4012_figure_2.png
+
.
```
- When a disturbance moves the top away from its initial vertical orientation with its stem up, the situation as shown in {numref}`Figure {number} <1q4012/figure_2.png>` will occur. The tippe top remains spinning around its centre of mass $\mathrm{CM}$ and point A, perpendicular below $\mathrm{C}$, slips over the floor. ({numref}`Figure {number} <1q4012/figure_3.png>` shows a photograph of the circular slip track made by a tippe top on a freshly painted surface.)
+ When a disturbance moves the top away from its initial vertical orientation with its stem up, the situation as shown in {numref}`Figure {number} <1q4012_figure_2.png>` will occur. The tippe top remains spinning around its centre of mass $\mathrm{CM}$ and point A, perpendicular below $\mathrm{C}$, slips over the floor. ({numref}`Figure {number} <1q4012_figure_3.png>` shows a photograph of the circular slip track made by a tippe top on a freshly painted surface.)
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1q4012_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1q4012/figure_3.png
----
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4013 Vibrating Stopwatch/1Q4013.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4013 Vibrating Stopwatch/1Q4013.md
index a48af5c4..1e41216c 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4013 Vibrating Stopwatch/1Q4013.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4013 Vibrating Stopwatch/1Q4013.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4013/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4013_figure_0.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/1Q4014.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/1Q4014.md
index aede0fb2..255eb09a 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/1Q4014.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/1Q4014.md
@@ -8,11 +8,10 @@ Direction of rolling is determined by direction of torque.
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4014/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4014_figure_0.png
+
.
```
@@ -24,17 +23,8 @@ name: 1q4014/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/2lsnQpFVnKQ?si=0lnTm9o0Aaor1f_c
+```
Show the simple construction of spool and wound thread to the students. The demonstrator takes the end of the thread in his hands and wants to pull in a horizontal direction. Ask the students in which direction the spool will roll. After their answers, pull .... and the spool will roll into the same direction as the demonstrator pulls.
@@ -43,34 +33,31 @@ The thread is wound to the spool again. The demonstrator takes the end of the th
These two demonstrations induce the idea that it should be possible to pull in such a direction that the spool will not roll at all! Ask the students in which direction you need to pull the thread to get this situation. After their answers, experimentally search the right angle: the spool skids.
## Explanation
-The direction in which the spool rolls is determined by the direction of the torque on the spool about the contact point. The critical angle is defined by extending the line of the pulled thread so that this line passes through the point of contact between the spool and the table. A force directed along this line produces zero torque on the spool about the contact point. (see {numref}`Figure {number} <1q4014/figure_1.png>`)
+The direction in which the spool rolls is determined by the direction of the torque on the spool about the contact point. The critical angle is defined by extending the line of the pulled thread so that this line passes through the point of contact between the spool and the table. A force directed along this line produces zero torque on the spool about the contact point. (see {numref}`Figure {number} <1q4014_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4014_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4014/figure_1.png
----
.
```
## Remarks
-- When pulling at very shallow angles, the spool orientation is not stable unless the thread comes off the spool at its center. This can be prevented by using a ribbon rather than a thread or using a large spool that is made in such a way that the thread can only be rolled in the centre of the spool ({numref}`Figure {number} <1q4014/figure_2.png>`).
+- When pulling at very shallow angles, the spool orientation is not stable unless the thread comes off the spool at its center. This can be prevented by using a ribbon rather than a thread or using a large spool that is made in such a way that the thread can only be rolled in the centre of the spool ({numref}`Figure {number} <1q4014_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4014_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4014/figure_2.png
----
.
```
-- A nice extension of this demonstration is to set the system up so that the string passes over a pulley and the force is supplied by hanging a weight from the end of the string ({numref}`Figure {number} <1q4014/figure_3.png>`).
+- A nice extension of this demonstration is to set the system up so that the string passes over a pulley and the force is supplied by hanging a weight from the end of the string ({numref}`Figure {number} <1q4014_figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1q4014/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1q4014_figure_3.png
+
.
```
If the spool is moved away from its critical angle, the spool will always roll back to the position of the critical angle! It will oscillate back and forth around this equilibrium position.
@@ -79,7 +66,6 @@ If the spool is moved away from its critical angle, the spool will always roll b
```{iframe} https://www.youtube.com/watch?v=tFHd8__h1QU
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/qr_images/qrcode_watch_v_tFHd8__h1QU.svg b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/qr_images/qrcode_watch_v_tFHd8__h1QU.svg
new file mode 100644
index 00000000..13556afb
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4014 Pulling a Spool/qr_images/qrcode_watch_v_tFHd8__h1QU.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/1Q4016.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/1Q4016.md
index 874f9a58..3e979c1b 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/1Q4016.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/1Q4016.md
@@ -14,11 +14,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4016/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4016_figure_0.png
+
.
```
@@ -35,17 +34,8 @@ name: 1q4016/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/enrU1xcXB8o?si=FoEwhBydM4p1t-oD
+```
1. The demonstrator sits on the swivel-chair and holds the bicycle wheel in front of him. The wheel is held with its axis vertical. The demonstrator spins the wheel and immediately he starts rotating in the opposite sense. When by hand he stops the wheel, also the swivel chair stops.
2. The demonstrator sits on the swivel chair. An assistant hands him the bicycle wheel that is spinning already around the vertical axis. Before doing so, ask the audience what will happen? Answer: nothing! But when the demonstrator slows down the bicycle wheel by braking it, the swivel-chair with demonstrator will start turning round in the same direction as the bicycle wheel did.
@@ -63,45 +53,41 @@ name: 1q4016/figure_0.png
## Explanation
1. Making the wheel turn, it obtains an angular velocity $\omega$ and an angular momentum $L=/ \omega$.
- Then the swivel chair has to turn in the opposite sense with an angular velocity $\omega^{'}$, whose angular momentum equals -/ $\omega$ (see {numref}`Figure {number} <1q4016/figure_1.png>`b), because the total angular momentum of the system has to remain zero as it is in the beginning of the demonstration ({numref}`Figure {number} <1q4016/figure_1.png>`a).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q4016/figure_1.png
----
+ Then the swivel chair has to turn in the opposite sense with an angular velocity $\omega^{'}$, whose angular momentum equals -/ $\omega$ (see {numref}`Figure {number} <1q4016_figure_1.png>`b), because the total angular momentum of the system has to remain zero as it is in the beginning of the demonstration ({numref}`Figure {number} <1q4016_figure_1.png>`a).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q4016_figure_1.png
+
.
```
-2. The wheel has an angular momentum of $L=/ \omega$ (see {numref}`Figure {number} <1q4016/figure_2.png>`a). This angular momentum is conserved, so when the wheel stops, the swivel chair with demonstrator will start to rotate (see $\omega^{'}$ in {numref}`Figure {number} <1q4016/figure_2.png>`b) in the same direction as $\omega$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q4016/figure_2.png
----
+2. The wheel has an angular momentum of $L=/ \omega$ (see {numref}`Figure {number} <1q4016_figure_2.png>`a). This angular momentum is conserved, so when the wheel stops, the swivel chair with demonstrator will start to rotate (see $\omega^{'}$ in {numref}`Figure {number} <1q4016_figure_2.png>`b) in the same direction as $\omega$.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q4016_figure_2.png
+
.
```
-3. When the rotating wheel has its axis in horizontal position ({numref}`Figure {number} <1q4016/figure_3.png>`a), then there is no angular momentum in the vertical direction. The swivel chair is not rotating.
+3. When the rotating wheel has its axis in horizontal position ({numref}`Figure {number} <1q4016_figure_3.png>`a), then there is no angular momentum in the vertical direction. The swivel chair is not rotating.
- Turning the wheel 90 upwards ({numref}`Figure {number} <1q4016/figure_3.png>`b), then an angular momentum is introduced in the vertical direction (/ $/ \omega$ ). This has to be compensated by another angular momentum of the same amount (-/ $/ \omega$ ) in order to keep the total angular momentum in the vertical direction zero: the swivel chair and demonstrator will rotate ( $\omega^{'}$ in {numref}`Figure {number} <1q4016/figure_3.png>`b).
+ Turning the wheel 90 upwards ({numref}`Figure {number} <1q4016_figure_3.png>`b), then an angular momentum is introduced in the vertical direction (/ $/ \omega$ ). This has to be compensated by another angular momentum of the same amount (-/ $/ \omega$ ) in order to keep the total angular momentum in the vertical direction zero: the swivel chair and demonstrator will rotate ( $\omega^{'}$ in {numref}`Figure {number} <1q4016_figure_3.png>`b).
- Bringing the wheel down (see {numref}`Figure {number} <1q4016/figure_3.png>`c) will make the swivel chair turn into the other direction.
+ Bringing the wheel down (see {numref}`Figure {number} <1q4016_figure_3.png>`c) will make the swivel chair turn into the other direction.
(The disappearance of $I \omega$ in the horizontal direction has no rotating effect, because the set up cannot rotate around a horizontal axis. The only effect is a torque felt by the demonstrator.)
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1q4016/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1q4016_figure_3.png
+
.
```
-4. In the beginning the wheel is turning, so there is an amount of angular momentum: $L=/ \omega$, and the swivel chair is standing still (see {numref}`Figure {number} <1q4016/figure_4.png>`a). Bringing the rotating wheel to a horizontal position removes that angular momentum from the system, but since angular momentum needs to be conserved, the whole system starts rotating ( $\omega^{'}$ ) in the same direction as $\omega$. When the wheel is lowered once more ({numref}`Figure {number} <1q4016/figure_4.png>`c), the figure makes clear that the swivel chair has to speed op to $2 \omega$.
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 1q4016/figure_4.png
----
+4. In the beginning the wheel is turning, so there is an amount of angular momentum: $L=/ \omega$, and the swivel chair is standing still (see {numref}`Figure {number} <1q4016_figure_4.png>`a). Bringing the rotating wheel to a horizontal position removes that angular momentum from the system, but since angular momentum needs to be conserved, the whole system starts rotating ( $\omega^{'}$ ) in the same direction as $\omega$. When the wheel is lowered once more ({numref}`Figure {number} <1q4016_figure_4.png>`c), the figure makes clear that the swivel chair has to speed op to $2 \omega$.
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 1q4016_figure_4.png
+
.
```
5. This is repeating the procedure of situation 4 a number of times. In the beginning the swivel chair is not rotating. At the end of the first round it rotates with $2 \omega$. Then after the second run it rotates with $4 \omega$, after the third run with $6 \omega$, and so on.
@@ -113,7 +99,6 @@ name: 1q4016/figure_4.png
```{iframe} https://www.youtube.com/watch?v=r0mFhT-rV1w
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/qr_images/qrcode_watch_v_r0mFhT_rV1w.svg b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/qr_images/qrcode_watch_v_r0mFhT_rV1w.svg
new file mode 100644
index 00000000..64434d68
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4016 Bicycle Wheel and Swivel Chair/qr_images/qrcode_watch_v_r0mFhT_rV1w.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4017 Train and Track/1Q4017.md b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4017 Train and Track/1Q4017.md
index 6e73e153..cc48f994 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4017 Train and Track/1Q4017.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q40 Cons of Angular Momentum/1Q4017 Train and Track/1Q4017.md
@@ -11,11 +11,10 @@ To show: Action and Reaction, or: Stable equilibrium, or: Conservation of Angula
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q4017/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q4017_figure_0.png
+
.
```
@@ -30,17 +29,8 @@ name: 1q4017/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/e6Vwg-fTCdk?si=KkNqwyGsiIvkP3sq
+```
### Preparation
The track and toy train are mounted as shown in the Diagram. The track is levelled carefully. To do this, first the complete frame is mounted and fixed to the table as level as possible. When the complete set is brought into the lecture-hall, further levelling is performed by means of the adjustable tabletop only.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5001 Precession/1Q5001.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5001 Precession/1Q5001.md
index e4ac85db..85470bf6 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5001 Precession/1Q5001.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5001 Precession/1Q5001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5001_figure_0.png
+
.
```
@@ -33,24 +32,22 @@ name: 1q5001/figure_0.png
## Explanation
Since angular momentum is a vector quantity that may be represented by a vector parallel to the axis of spin, the combination of two angular moments may be treated by the parallelogram law.
-The spinning gyroscope has an angular momentum of $I\omega_0$. This is represented by a vector parallel to the axis of spin (see {numref}`Figure {number} <1q5001/figure_1.png>`a).
+The spinning gyroscope has an angular momentum of $I\omega_0$. This is represented by a vector parallel to the axis of spin (see {numref}`Figure {number} <1q5001_figure_1.png>`a).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5001/figure_1.png
----
.
```
-When the centre of mass ($\mathrm{~CM}$) is above the point of support, then there is a gravitational torque mgs (see {numref}`Figure {number} <1q5001/figure_1.png>`b), pointing away from you.
+When the centre of mass ($\mathrm{~CM}$) is above the point of support, then there is a gravitational torque mgs (see {numref}`Figure {number} <1q5001_figure_1.png>`b), pointing away from you.
+
+This torque tends to change $I\omega_0$, so $I\omega_0$ moves into the direction of $mgs$ (see {numref}`Figure {number} <1q5001_figure_2.png>`),
-This torque tends to change $I\omega_0$, so $I\omega_0$ moves into the direction of $mgs$ (see {numref}`Figure {number} <1q5001/figure_2.png>`),
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q5001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q5001/figure_2.png
----
.
```
and in that way changes the axis of rotation of the wheel (precession).
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5002 Precessing Orbit/1Q5002.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5002 Precessing Orbit/1Q5002.md
index b7780f13..3fe93a31 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5002 Precessing Orbit/1Q5002.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5002 Precessing Orbit/1Q5002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5002_figure_0.png
+
.
```
@@ -50,11 +49,10 @@ When $U(0)=0$ and $U^{'}(0)=0$ (minimum at $r=0$, the center of the bowl) and wh
This is a harmonic potential, and when moving in a line with small amplitudes, we'll see a harmonic motion. This harmonic potential $\left(r^{2}\right)$ is clearly NOT a $r^{-1}$-potential.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5002_figure_1.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5003 Precession AND Nutation/1Q5003.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5003 Precession AND Nutation/1Q5003.md
index 08222e8f..65f0f6d6 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5003 Precession AND Nutation/1Q5003.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5003 Precession AND Nutation/1Q5003.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5003_figure_0.png
+
.
```
@@ -28,22 +27,21 @@ name: 1q5003/figure_0.png
## Presentation
The gyroscope has its base levelled and its counterweights adjusted until the gyroscope is balanced. The loop of thread is put around the pulley and pulled, to give the disk a high speed of rotation. Observe the direction of rotation and place the gyroscope-axis horizontal. The gyroscope is balanced in this situation.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5003/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5003_figure_1.png
+
.
```
-1. Give by hand a sharp downward blow at the end of the gyroscope-axis. Now the axis moves conically around a fixed center (nutation). This center is a little to the right or to the left (depending on the direction of the disk's rotation) of the initial starting position of the gyroscope-axis (see {numref}`Figure {number} <1q5003/figure_1.png>`-1; looking at the axes makes that the red figure is in reality a circle).
+1. Give by hand a sharp downward blow at the end of the gyroscope-axis. Now the axis moves conically around a fixed center (nutation). This center is a little to the right or to the left (depending on the direction of the disk's rotation) of the initial starting position of the gyroscope-axis (see {numref}`Figure {number} <1q5003_figure_1.png>`-1; looking at the axes makes that the red figure is in reality a circle).
When this demonstration is repeated with a slower rotating gyroscope-disk, then it will be observed that the resulting nutation frequency is lower.
-2. Restart the original horizontally balanced gyroscope rotation at a not too fast speed. While holding the rotation-axis in the horizontal position, the slotted mass is placed on the end of the axis. The gyroscope is released and shows now nutation and precession at the same time. The axis of rotation shows a cycloidic displacement (see {numref}`Figure {number} <1q5003/figure_1.png>`-2).
-3. Restart the original horizontally balanced gyroscope at a not too fast speed. Place again the slotted mass and hold the axis in the horizontal position. Release the gyroscope and on releasing give it a slight push in the direction opposite to the precession. The cycloidic nutation-pattern will have loops now (see {numref}`Figure {number} <1q5003/figure_1.png>`-3).
-4. Restart the original horizontally balanced gyroscope at a not too fast speed. Place again the slotted mass and hold the axis in the horizontal position. Release the gyroscope and on releasing give it a slight push in the direction of the precession. The sharply-pointed cycloidic pattern becomes more wave-like now (see {numref}`Figure {number} <1q5003/figure_1.png>`-4a).
+2. Restart the original horizontally balanced gyroscope rotation at a not too fast speed. While holding the rotation-axis in the horizontal position, the slotted mass is placed on the end of the axis. The gyroscope is released and shows now nutation and precession at the same time. The axis of rotation shows a cycloidic displacement (see {numref}`Figure {number} <1q5003_figure_1.png>`-2).
+3. Restart the original horizontally balanced gyroscope at a not too fast speed. Place again the slotted mass and hold the axis in the horizontal position. Release the gyroscope and on releasing give it a slight push in the direction opposite to the precession. The cycloidic nutation-pattern will have loops now (see {numref}`Figure {number} <1q5003_figure_1.png>`-3).
+4. Restart the original horizontally balanced gyroscope at a not too fast speed. Place again the slotted mass and hold the axis in the horizontal position. Release the gyroscope and on releasing give it a slight push in the direction of the precession. The sharply-pointed cycloidic pattern becomes more wave-like now (see {numref}`Figure {number} <1q5003_figure_1.png>`-4a).
-5. The slight push in the direction of precession can be made that strong that the nutation (almost) disappears (see {numref}`Figure {number} <1q5003/figure_1.png>`-4b). This situation is called "regular precession".
+5. The slight push in the direction of precession can be made that strong that the nutation (almost) disappears (see {numref}`Figure {number} <1q5003_figure_1.png>`-4b). This situation is called "regular precession".
## Explanation
@@ -56,7 +54,7 @@ name: 1q5003/figure_1.png
- Adding a weight simulates (in an extreme way) the general situation of unbalanced massdistribution. For this reason all rotating real objects show nutation (for instance, the Earth).
## Remarks
- * {numref}`Figure {number} <1q5003/figure_1.png>` contains data registered on the demonstration gyroscope by using two Rotary Motion sensors (PASCO CI-6538) in combination with PASCO-software (Science Workshop).
+ * {numref}`Figure {number} <1q5003_figure_1.png>` contains data registered on the demonstration gyroscope by using two Rotary Motion sensors (PASCO CI-6538) in combination with PASCO-software (Science Workshop).
* When you are experienced, step 2 - 5 in the Presentation can be performed in one run of the gyroscope, provided the gyroscope is not slowing down too much. But remenber that the audience is not experienced and needs time to digest four different demonstrations! So
, no need to hurry.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/1Q5004.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/1Q5004.md
index 1f0de0d9..1dcd5a9c 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/1Q5004.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/1Q5004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5004_figure_0.png
+
.
```
@@ -24,31 +23,21 @@ name: 1q5004/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/EutntrR6P5E?si=VnCF6d6sR37rEBOn
+```
The wheel is supported by strings tied to both handles. The wheel is given a fast spin by hand. Now one of the supporting strings is cut. The wheel starts to precess about a vertical axis (while its own horizontal axis of spin slowly descends toward the vertical). As the spin of the wheel diminishes, the wheel precesses more rapidly.
## Explanation
Since angular momentum is a vector quantity that may be conveniently represented by a vector parallel to the axis of spin, the combination of two angular momenta may be treated by the parallelogram law. Thus, whenever a gyroscope is acted upon by a torque tending to produce rotation about an axis perpendicular to the axis of spin, the gyroscope will precess about a third axis perpendicular to the other two.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5004/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5004_figure_1.png
+
.
```
-The spinning wheel has an angular momentum of $I \omega_{0}$. This is represented by a vector parallel to the axis of spin (see {numref}`Figure {number} <1q5004/figure_1.png>` a). When one of the strings is cut, then gravitational torque ( $\mathrm{mgs}$ ) is added to the system (see {numref}`Figure {number} <1q5004/figure_1.png>` b ). This torque tends to change $I \omega_{0}$, so $I \omega_{b}$ moves into the direction of $m g s$ (see {numref}`Figure {number} <1q5004/figure_1.png>` c).
+The spinning wheel has an angular momentum of $I \omega_{0}$. This is represented by a vector parallel to the axis of spin (see {numref}`Figure {number} <1q5004_figure_1.png>` a). When one of the strings is cut, then gravitational torque ( $\mathrm{mgs}$ ) is added to the system (see {numref}`Figure {number} <1q5004_figure_1.png>` b ). This torque tends to change $I \omega_{0}$, so $I \omega_{b}$ moves into the direction of $m g s$ (see {numref}`Figure {number} <1q5004_figure_1.png>` c).
It can be shown that the speed of precession $\left(\omega_{p}\right)$ is given by $\omega_{p}=\frac{m g s}{I \omega_{f}}$, so slowing down of $\omega_{0}$ increases $\omega_{0}$. The precession will also be more rapid by adding a weight to the unsupported handle.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/qr_images/qrcode_EutntrR6P5E_si_VnCF6d6sR37rEBOn_.svg b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/qr_images/qrcode_EutntrR6P5E_si_VnCF6d6sR37rEBOn_.svg
new file mode 100644
index 00000000..b847df0a
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5004 Precession/qr_images/qrcode_EutntrR6P5E_si_VnCF6d6sR37rEBOn_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5006 Nutation/1Q5006.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5006 Nutation/1Q5006.md
index 602321d5..36d6b4ab 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5006 Nutation/1Q5006.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5006 Nutation/1Q5006.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5006_figure_0.png
+
.
```
@@ -29,23 +28,21 @@ The pointed support is shifted so that the gyroscope is supported at its centre
Now a short blow is given to the axis of the spinning gyroscope. It now performs an additional rotary motion; the axis moves conically. This movement is called nutation. If the colored segment is fixed on the top-side of the ball bearing, the instantaneous axis of spin is made visible. (Individual colors will be seen, but everywhere else they will merge to a uniform 'grey'.)
## Explanation
-When the gyroscope is spinning, it has an angular momentum of $I_{0} \omega_{0}$ (see {numref}`Figure {number} <1q5006/figure_1.png>`a). When a short blow is given, an extra angular momentum ( $\triangle L$ ) is added to the spinning wheel (see {numref}`Figure {number} <1q5006/figure_1.png>`b; the short blow is given to the upper part of the axis in the direction of the observer). This leads to a total angular momentum $L$, which is constant from then on.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5006/figure_1.png
----
+When the gyroscope is spinning, it has an angular momentum of $I_{0} \omega_{0}$ (see {numref}`Figure {number} <1q5006_figure_1.png>`a). When a short blow is given, an extra angular momentum ( $\triangle L$ ) is added to the spinning wheel (see {numref}`Figure {number} <1q5006_figure_1.png>`b; the short blow is given to the upper part of the axis in the direction of the observer). This leads to a total angular momentum $L$, which is constant from then on.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5006_figure_1.png
+
.
```
-$\Delta L$ corresponds with a rotation $\omega^{'}=\frac{\Delta L}{I^{'}}$. The resultant of $\omega_{0}$ and $\omega^{'}$ is the momentary angular velocity $\omega$ (see {numref}`Figure {number} <1q5006/figure_2.png>`a). This resultant $\omega$ does not have the same direction as $L$, since $I^{'}`b, the axis of momentary angular velocity moves in a cone around the fixed axis of $L$. Then also the symmetry-axis of the gyroscope moves in a cone around the axis of $L$. This cone is called the cone of nutation.
+$\Delta L$ corresponds with a rotation $\omega^{'}=\frac{\Delta L}{I^{'}}$. The resultant of $\omega_{0}$ and $\omega^{'}$ is the momentary angular velocity $\omega$ (see {numref}`Figure {number} <1q5006_figure_2.png>`a). This resultant $\omega$ does not have the same direction as $L$, since $I^{'}`b, the axis of momentary angular velocity moves in a cone around the fixed axis of $L$. Then also the symmetry-axis of the gyroscope moves in a cone around the axis of $L$. This cone is called the cone of nutation.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q5006_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q5006/figure_2.png
----
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5007 Nutation/1Q5007.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5007 Nutation/1Q5007.md
index 2c444ff0..2c28becf 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5007 Nutation/1Q5007.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5007 Nutation/1Q5007.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5007_figure_0.png
+
.
```
@@ -22,11 +21,10 @@ name: 1q5007/figure_0.png
## Presentation
Watching a nutating object we observe that the body-axis makes a conical movement (see [Nutation](../1Q5006%20Nutation/1Q5006.md). This movement of the body-axis is visualized in our model by rotating the $L$-axis by hand (see Figures).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5007/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5007_figure_1.png
+
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/1Q5008.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/1Q5008.md
index fe1a12be..a5319bf1 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/1Q5008.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/1Q5008.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5008/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5008_figure_0.png
+
.
```
@@ -26,23 +25,21 @@ name: 1q5008/figure_0.png
The wheel is rotating and held by a string. The rotating wheel has an angle of about $45^{\circ}-60^{\circ}$ with the vertical. The wheel will precess about a vertical axis. When the instructor pushes with the side of his hands or a stick against one of the handles of the wheel in the direction of precession, then the rotating wheel will rise to a more vertical position. This can be continued, even passing the vertical.
## Explanation
-The rotating wheel will precess due to gravitational torque, $m g s$ ( $I \omega_{0}$ moves in the direction of this gravitational torque; precession) (see {numref}`Figure {number} <1q5008/figure_1.png>`a).
+The rotating wheel will precess due to gravitational torque, $m g s$ ( $I \omega_{0}$ moves in the direction of this gravitational torque; precession) (see {numref}`Figure {number} <1q5008_figure_1.png>`a).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5008/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5008_figure_1.png
+
.
```
-$F$ is the applied force in the direction of precession (see {numref}`Figure {number} <1q5008/figure_1.png>`b). The applied torque is pointing vertically upward, so now $I \omega_{0}$ moves also upward.
+$F$ is the applied force in the direction of precession (see {numref}`Figure {number} <1q5008_figure_1.png>`b). The applied torque is pointing vertically upward, so now $I \omega_{0}$ moves also upward.
## Video Rhett Allain
```{iframe} https://www.youtube.com/watch?v=r__nGqGpTD8
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/qr_images/qrcode_watch_v_r__nGqGpTD8.svg b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/qr_images/qrcode_watch_v_r__nGqGpTD8.svg
new file mode 100644
index 00000000..3c326ca3
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5008 Precession/qr_images/qrcode_watch_v_r__nGqGpTD8.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5009 Precession/1Q5009.md b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5009 Precession/1Q5009.md
index ac63f620..637ec80a 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5009 Precession/1Q5009.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q50 Gyros/1Q5009 Precession/1Q5009.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q5009/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q5009_figure_0.png
+
.
```
@@ -33,15 +32,14 @@ As soon as you stop speeding up the rotating platform, the lifting of the spinni
Leaving the spinning bicycle wheel to itself now, it slowly comes down, and the rotating platform speeds up.
## Explanation
-The spinning bicycle wheel has an angular momentum of $I_{1} \omega_{0}$. Rotating the platform, introduces a torque $T$. This torque tends to change $I_{1} \omega_{0}$, so $I_{1} \omega_{b}$ moves into the direction of $T$. So, when $T$ is pointing upward, $I_{1} \omega_{0}$ moves upward: the bicycle wheel handle lifts itself from the support. (See {numref}`Figure {number} <1q5009/figure_1.png>`a.)
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q5009/figure_1.png
----
+The spinning bicycle wheel has an angular momentum of $I_{1} \omega_{0}$. Rotating the platform, introduces a torque $T$. This torque tends to change $I_{1} \omega_{0}$, so $I_{1} \omega_{b}$ moves into the direction of $T$. So, when $T$ is pointing upward, $I_{1} \omega_{0}$ moves upward: the bicycle wheel handle lifts itself from the support. (See {numref}`Figure {number} <1q5009_figure_1.png>`a.)
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q5009_figure_1.png
+
.
```
-While the platform is freely rotating, gravitational torque $m g s$ is acting (see {numref}`Figure {number} <1q5009/figure_1.png>`b). In {numref}`Figure {number} <1q5009/figure_1.png>`b this torque is pointing out to the reader. $I_{1} \omega_{0}$ moves into the direction of $m g s$, keeping the platform rotating (precession). In this process, increases because the bicyclewheel is coming down. Since $\omega_{p}=\frac{m g s}{I_{0} \omega_{0}}, \omega_{p}$ increases due to $s$ becoming larger (and also a little due to $\omega_{0}$ becoming smaller).
+While the platform is freely rotating, gravitational torque $m g s$ is acting (see {numref}`Figure {number} <1q5009_figure_1.png>`b). In {numref}`Figure {number} <1q5009_figure_1.png>`b this torque is pointing out to the reader. $I_{1} \omega_{0}$ moves into the direction of $m g s$, keeping the platform rotating (precession). In this process, increases because the bicyclewheel is coming down. Since $\omega_{p}=\frac{m g s}{I_{0} \omega_{0}}, \omega_{p}$ increases due to $s$ becoming larger (and also a little due to $\omega_{0}$ becoming smaller).
## Remarks
- Our setup is in such a way that $s$ changes substantially when the wheel comes down. When our wheel is at about $45^{\circ}, s=0$.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6003 Stable Wheel/1Q6003.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6003 Stable Wheel/1Q6003.md
index e948ec44..9cde7f23 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6003 Stable Wheel/1Q6003.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6003 Stable Wheel/1Q6003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6003_figure_0.png
+
.
```
@@ -26,26 +25,24 @@ name: 1q6003/figure_0.png
- Then the wheel is released while turning. It rolls over the floor and remains upright for a much longer time.
- The second observation made is that it will follow a curve when it starts falling down. Also notice that the curve it makes, is into the direction of the "falling down" (see {numref}`Figure {number} <1q6003/figure_1.png>`).
+ The second observation made is that it will follow a curve when it starts falling down. Also notice that the curve it makes, is into the direction of the "falling down" (see {numref}`Figure {number} <1q6003_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6003/figure_1.png
----
.
```
## Explanation
-{numref}`Figure {number} <1q6003/figure_2.png>`A shows the wheel turning. The rotation is indicated by means of the vector $\underline{\omega}$. Due to some disturbance, the wheel inclines due to gravity: a torque ( $\tau$ ) is acting on the wheel (see {numref}`Figure {number} <1q6003/figure_2.png>`).
+{numref}`Figure {number} <1q6003_figure_2.png>`A shows the wheel turning. The rotation is indicated by means of the vector $\underline{\omega}$. Due to some disturbance, the wheel inclines due to gravity: a torque ( $\tau$ ) is acting on the wheel (see {numref}`Figure {number} <1q6003_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q6003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q6003/figure_2.png
----
.
```
-Due to this torque the direction of the vector $\underline{\omega}$ is changed: $\underline{\omega}$ is changed into the direction of $\tau$ (see {numref}`Figure {number} <1q6003/figure_2.png>`C), so the wheel will make a curve while rolling. This continues because the vectors $\underline{\omega}$ and $\tau$ remain perpendicular to each other.
+Due to this torque the direction of the vector $\underline{\omega}$ is changed: $\underline{\omega}$ is changed into the direction of $\tau$ (see {numref}`Figure {number} <1q6003_figure_2.png>`C), so the wheel will make a curve while rolling. This continues because the vectors $\underline{\omega}$ and $\tau$ remain perpendicular to each other.
Also can be seen now that the larger the inclination, the sharper the curve it will make since vector $\vec{r}$ increases, making $\vec{tau}$ larger.
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6004 Percussionpoint/1Q6004.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6004 Percussionpoint/1Q6004.md
index 661e1c62..e08866e5 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6004 Percussionpoint/1Q6004.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6004 Percussionpoint/1Q6004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6004_figure_0.png
+
.
```
@@ -32,24 +31,22 @@ name: 1q6004/figure_0.png
The point, around which the stick rotates is called "percussion point". In point 3 and -4 , this point is on the stick; in point 2 it is outside the stick.
## Explanation
-Due to the short blow, the ruler performs a movement that can be considered as consisting of two movements: a translation and rotation around its center of mass $\mathrm{~CM}$ (see {numref}`Figure {number} <1q6004/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6004/figure_1.png
----
+Due to the short blow, the ruler performs a movement that can be considered as consisting of two movements: a translation and rotation around its center of mass $\mathrm{~CM}$ (see {numref}`Figure {number} <1q6004_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6004_figure_1.png
+
.
```
During the short blow force acts on the ruler. The total momentum of this force is $\int F dt=p$. The ruler gets a speed $v_{c}$, so the momentum of the ruler is $m v_{c}$. This makes $v_{c}=p / m$.
-Relative to $\mathrm{CM}$ the ruler has also an angular momentum $I_{c} \omega_{c}=b p$ (see {numref}`Figure {number} <1q6004/figure_2.png>`). So $\omega_{c}=b p / I_{c}$ On one side of $\mathrm{CM}, v_{c}$ and $\omega_{c}$ have the same direction; on the other side $v_{c}$ and $\omega_{c}$ are opposite to each other. Looking at point A: $v_{A}=v_{c}-\omega_{c} x$. When point A remains at rest after the blow (A is then the so-called percussion point) then $0=v_{c}-\omega_{c} x$. This happens at $x=\frac{v_{c}}{\omega_{c}}=\frac{p / m}{b p / I_{c}}=\frac{I_{c}}{m b}$. For this ruler: $I_{c}=1 / 12 m l^{2}$, making $x=\frac{1}{12} \frac{l^{2}}{b}$.
+Relative to $\mathrm{CM}$ the ruler has also an angular momentum $I_{c} \omega_{c}=b p$ (see {numref}`Figure {number} <1q6004_figure_2.png>`). So $\omega_{c}=b p / I_{c}$ On one side of $\mathrm{CM}, v_{c}$ and $\omega_{c}$ have the same direction; on the other side $v_{c}$ and $\omega_{c}$ are opposite to each other. Looking at point A: $v_{A}=v_{c}-\omega_{c} x$. When point A remains at rest after the blow (A is then the so-called percussion point) then $0=v_{c}-\omega_{c} x$. This happens at $x=\frac{v_{c}}{\omega_{c}}=\frac{p / m}{b p / I_{c}}=\frac{I_{c}}{m b}$. For this ruler: $I_{c}=1 / 12 m l^{2}$, making $x=\frac{1}{12} \frac{l^{2}}{b}$.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q6004_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q6004/figure_2.png
----
.
```
Applying this to the different situations of the Presentation shows the observed percussion points: in PresentationXX point 1 $(b=0)$, point 3 $(b=.5 \mathrm{~m})$ and point 4 $(b=.17 \mathrm{~m})$. In PresentationXX $(b=.1 \mathrm{~m})$, the percussion point is outside the ruler $(x=.83 \mathrm{~m})$.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6005 Percussionpoint/1Q6005.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6005 Percussionpoint/1Q6005.md
index 0feb7d96..c1feb421 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6005 Percussionpoint/1Q6005.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6005 Percussionpoint/1Q6005.md
@@ -8,16 +8,15 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6005_figure_0.png
+
.
```
## Equipment
-- Baseball bat and "cradle" (see {numref}`Figure {number} <1q6005/figure_1.png>`A).
+- Baseball bat and "cradle" (see {numref}`Figure {number} <1q6005_figure_1.png>`A).
- Meter stick.
- Mathematical pendulum.
- Rubber hammer.
@@ -25,20 +24,19 @@ name: 1q6005/figure_0.png
## Presentation
1. The meterstick is suspended as a physical pendulum. The point of suspension is the percussion point when the stick is hit at about $67 \mathrm{~cm}$ (see demonstration [Percussion point](../1Q6004%20Percussionpoint/1Q6004.md). The distance of $67 \mathrm{~cm}$ is also the reduced length of this pendulum (see demonstration [Physical pendulum (1)](/book/3%20oscillations%20and%20waves/3A%20osc/3A15%20Physical%20Pendula/3A1501%20Physical%20Pendulum/3A1501.md). This is quickly shown by suspending a "mathematical" pendulum close to the suspended stick (see the arrangement on the left side of Diagram) and making both swing: when the "mathematical" pendulum has a length of $67 \mathrm{~cm}$, they will have the same period; swinging together, they stay together. The conclusion can be that when you hit the stick at the point of reduced length, the point of suspension will be the percussion point.
-2. The baseballbat has a hole drilled in its shaft at the point between the two hands that would grasp the bat. In this hole a bar is stuck, extending on both sides. These ends rest on the flat surfaces of the "cradle" (see {numref}`Figure {number} <1q6005/figure_1.png>`A), so the bat can rock to and fro.
+2. The baseballbat has a hole drilled in its shaft at the point between the two hands that would grasp the bat. In this hole a bar is stuck, extending on both sides. These ends rest on the flat surfaces of the "cradle" (see {numref}`Figure {number} <1q6005_figure_1.png>`A), so the bat can rock to and fro.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6005_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6005/figure_1.png
----
.
```
Using the rubber hammer, the bat is hit close to its point of suspension: The bat swings and on its horizontal surfaces of suspension it also displaces itself into the direction the hammer was hitting.
Then the hammer hits the bat at its lowest point. Again the bat swings, but now the displacement on the surface of suspension is into a direction opposite to the hitting hammer.
-Conclusion will be that somewhere in between, the bat can be hit causing only a rotation at the suspension point. (By trial and error this point can be located.) We mount the mathematical pendulum close to the bat (see {numref}`Figure {number} <1q6005/figure_1.png>` B) and increase its length until it swings with the same period as the free suspended bat does. Then we hit the bat at the point indicated by the bob of the mathematical pendulum, and the bat only rotates at the suspension point; there is no translation.
+Conclusion will be that somewhere in between, the bat can be hit causing only a rotation at the suspension point. (By trial and error this point can be located.) We mount the mathematical pendulum close to the bat (see {numref}`Figure {number} <1q6005_figure_1.png>` B) and increase its length until it swings with the same period as the free suspended bat does. Then we hit the bat at the point indicated by the bob of the mathematical pendulum, and the bat only rotates at the suspension point; there is no translation.
## Explanation
In the Explanation of the demonstration [Physical pendulum (1)](/book/3%20oscillations%20and%20waves/3A%20osc/3A15%20Physical%20Pendula/3A1501%20Physical%20Pendulum/3A1501.md), it is shown that the reduced length of a physical pendulum equals $\frac{I_{c}}{\mathrm{~ms}}+c$. In the Explanation of the demonstration [Percussion point](../1Q6004%20Percussionpoint/1Q6004.md) it is shown that $x=\frac{I_{c}}{m b}$, while the percussion point is $\mathrm{b}+\mathrm{x}$ away from the point of hitting. Comparing both explanations, it is easy to see that $\frac{I_{c}}{m c}+s=\frac{I_{c}}{m b}+b$ :
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6006 Sleeper/1Q6006.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6006 Sleeper/1Q6006.md
index 8255c40f..0d383ec9 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6006 Sleeper/1Q6006.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6006 Sleeper/1Q6006.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6006/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6006_figure_0.png
+
.
```
@@ -22,7 +21,7 @@ name: 1q6006/figure_0.png
* Top with felt-pen
* Bicycle wheel with handles, the handles fixed
* Hard surface to spin the tops on
- * White standard hardboard (about $50 \times 50 \mathrm{~cm2^}$)
+ * White standard hardboard (about $50 \times 50 \mathrm{~cm}^2$)
## Presentation
- Spin the small top with a quick snap of your fingers, in such a way that the top starts spinning having its spinning axis make a quite large angle with the vertical. The top runs in an arc and very soon stands vertically upright. When disturbing this upright position the vertical position returns very quickly; the vertical position appears to be very stable.
@@ -37,16 +36,15 @@ When the top slows down, it increases its angle with the vertical and finally to
## Explanation
The top, being almost a free body, moves around its centre of mass (CM), which remains stationary.
-Due to its tilted position, the spinning top will precess ( $I_{0} \omega_{0}$ moves into the direction of gravitational torque $T_{p}$, see {numref}`Figure {number} <1q6006/figure_1.png>`a.).
+Due to its tilted position, the spinning top will precess ( $I_{0} \omega_{0}$ moves into the direction of gravitational torque $T_{p}$, see {numref}`Figure {number} <1q6006_figure_1.png>`a.).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6006_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6006/figure_1.png
----
.
```
-As a result the rounded stem of the top is attempting to roll over the floor in two ways: one due to the spin of the top around its body-axis and the other due to precession driving the stem over the floor. The first way is much faster than the second and so the rounded stem slips: it slips into the direction of spin. The friction force on the stem in point $\mathrm{C}$ is opposite to the slip, so friction is directed backwards (see {numref}`Figure {number} <1q6006/figure_1.png>`b). The torque of this friction force ( $T_{f}$ ) is almost perpendicular to $I_{0} \omega_{0}$, so $I_{0} \omega_{0}$ continues to rise until the top is positioned vertical ( $T_{f}$ will tend to align $I_{o} \omega_{0}$ ). The orientation of the top follows that of $I_{0} \omega_{0}$, and the top rights itself.
+As a result the rounded stem of the top is attempting to roll over the floor in two ways: one due to the spin of the top around its body-axis and the other due to precession driving the stem over the floor. The first way is much faster than the second and so the rounded stem slips: it slips into the direction of spin. The friction force on the stem in point $\mathrm{C}$ is opposite to the slip, so friction is directed backwards (see {numref}`Figure {number} <1q6006_figure_1.png>`b). The torque of this friction force ( $T_{f}$ ) is almost perpendicular to $I_{0} \omega_{0}$, so $I_{0} \omega_{0}$ continues to rise until the top is positioned vertical ( $T_{f}$ will tend to align $I_{o} \omega_{0}$ ). The orientation of the top follows that of $I_{0} \omega_{0}$, and the top rights itself.
Once perfectly vertical the friction force is no longer present, but any disturbance moving the top away from the vertical immediately introduces a raising torque again, restoring its vertical position.
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/1Q6007.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/1Q6007.md
index af451905..b8a51cd1 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/1Q6007.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/1Q6007.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6007/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6007_figure_0.png
+
.
```
@@ -27,17 +26,8 @@ name: 1q6007/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/-HP7HtscYoc?si=lxGWa56vZrWg9Uf1
+```
- Spin the tippe top (nr.1) with a quick snap of your fingers. It will spin with its hemispherical bottom downwards. After a short time the top turns over and spins on the stem. It continues to rotate on its stem, slows down and finally falls, resuming its position with stem up.
- Take tippe top nr.2, with the arrows painted on it. Repeat what seems to be the motion of the top without actually releasing it, that is: hold the stem of the top in the normal starting position (stem up) and twist the stem between thumb and forefinger, in the direction of the arrows painted on it. At the same time rotate the hand slowly to invert the top. The audience can clearly see that the inverted top continues to rotate in the direction of the arrow, but seen from the outside the sense of rotation is in the opposite direction. When you show this to a large audience you can use the transparent disc with the arrow painted on it to show this.
@@ -49,12 +39,11 @@ name: 1q6007/figure_0.png
## Explanation
-The top consists of a hollow sphere that is sliced off with a stem attached to it. This top is in stable static equilibrium when it points its stem upward, so the centre of mass (CM) is below the centre of curvature (C). This top is given a spin $\omega_{0}$ (see {numref}`Figure {number} <1q6007/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6007/figure_1.png
----
+The top consists of a hollow sphere that is sliced off with a stem attached to it. This top is in stable static equilibrium when it points its stem upward, so the centre of mass (CM) is below the centre of curvature (C). This top is given a spin $\omega_{0}$ (see {numref}`Figure {number} <1q6007_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6007_figure_1.png
+
.
```
Now the tippe top has an amount of angular momentum $\left(L_{0}\right)$. The demonstrations with tippe top nr. 2 , nr. 3 and nr. 1 on the painted board, show that this vertical angular momentum remains predominantly in that direction during the entire inversion process: $L_{0}$ keeps during this demonstration the same direction. (Thus the direction of rotation of the tippe top with respect to the coordinates fixed in its body is reversed.)
@@ -63,20 +52,18 @@ During inversion the centre of mass of the tippe top is elevated; it follows tha
A complete analysis to account for the behavior of the top is quite elaborate (see SourcesXX). Next a simplified explanation is attempted:
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q6007/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q6007_figure_2.png
+
.
```
- When a disturbance moves the top away from its initial vertical orientation with its stem up, the situation as shown in {numref}`Figure {number} <1q6007/figure_2.png>` will occur. The tippe top remains spinning around its centre of mass $\mathrm{CM}$ and point A, perpendicular below $\mathrm{C}$, slips over the floor. ({numref}`Figure {number} <1q6007/figure_3.png>` shows a photograph of the circular slip track made by a tippe top on a freshly painted surface.)
+ When a disturbance moves the top away from its initial vertical orientation with its stem up, the situation as shown in {numref}`Figure {number} <1q6007_figure_2.png>` will occur. The tippe top remains spinning around its centre of mass $\mathrm{CM}$ and point A, perpendicular below $\mathrm{C}$, slips over the floor. ({numref}`Figure {number} <1q6007_figure_3.png>` shows a photograph of the circular slip track made by a tippe top on a freshly painted surface.)
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 1q6007_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 1q6007/figure_3.png
----
.
```
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/qr_images/qrcode__HP7HtscYoc_si_lxGWa56vZrWg9Uf1_.svg b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/qr_images/qrcode__HP7HtscYoc_si_lxGWa56vZrWg9Uf1_.svg
new file mode 100644
index 00000000..02d7cc67
--- /dev/null
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6007 Tippe Top/qr_images/qrcode__HP7HtscYoc_si_lxGWa56vZrWg9Uf1_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6008 Rugbyball/1Q6008.md b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6008 Rugbyball/1Q6008.md
index 35bc3e3c..2d2c07c8 100644
--- a/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6008 Rugbyball/1Q6008.md
+++ b/book/book/1 mechanics/1Q rot dyn/1Q60 Rot Stability/1Q6008 Rugbyball/1Q6008.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 1q6008/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 1q6008_figure_0.png
+
.
```
@@ -21,26 +20,24 @@ name: 1q6008/figure_0.png
* Rugby ball
## Presentation
-The rugby ball lies on the floor. By hand it is given a fast spin around its short axis (see {numref}`Figure {number} <1q6008/figure_1.png>`).
+The rugby ball lies on the floor. By hand it is given a fast spin around its short axis (see {numref}`Figure {number} <1q6008_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 1q6008_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 1q6008/figure_1.png
----
.
```
When the ball has made some turns it lifts itself, finally standing on its nose (tail) and rotating around its long axis.
## Explanation
-- When the ball turns around its short axis ( $\omega_{s}$ ) it will tilt its long axis a little due to unbalanced mass distribution. Then spinning around its long axis $\left(\omega_{/}\right)$ will start (see {numref}`Figure {number} <1q6008/figure_2.png>`) and at the same time, the long axis starts a precession ( $I_{2} \omega_{1}$ moves into the direction of $T_{p}$ ).
+- When the ball turns around its short axis ( $\omega_{s}$ ) it will tilt its long axis a little due to unbalanced mass distribution. Then spinning around its long axis $\left(\omega_{/}\right)$ will start (see {numref}`Figure {number} <1q6008_figure_2.png>`) and at the same time, the long axis starts a precession ( $I_{2} \omega_{1}$ moves into the direction of $T_{p}$ ).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 1q6008_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 1q6008/figure_2.png
----
.
```
- The point of contact slips on the floor (see Diagram). The friction force $\left(F_{f}\right)$ on the ball is pointing in the same direction as its direction of precession. The torque ( $T_{f}$ ) of this friction force is pointing upward (see Diagram), almost perpendicular to $I_{2} \omega_{\nu}$. So the friction force gives a torque that erects the ball ( $I_{2} \omega /$ moves into the direction of $T_{f}$ ).
diff --git a/book/book/2 fluid mechanics/2B statics/2B20 Static Pressure/2B2001 Rotating Liquid/2B2001.md b/book/book/2 fluid mechanics/2B statics/2B20 Static Pressure/2B2001 Rotating Liquid/2B2001.md
index 5da928db..c25494f9 100644
--- a/book/book/2 fluid mechanics/2B statics/2B20 Static Pressure/2B2001 Rotating Liquid/2B2001.md
+++ b/book/book/2 fluid mechanics/2B statics/2B20 Static Pressure/2B2001 Rotating Liquid/2B2001.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 2b2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 2b2001_figure_0.png
+
.
```
@@ -25,35 +24,32 @@ name: 2b2001/figure_0.png
## Presentation
- The glass beaker is half filled with water. The beaker is submerged in a square reservoir (see Diagram). By means of the electric motor the glass is made rotating. Gradually the liquid climbs the wall of the beaker until it settles itself. The paraboloidic shape can be seen clearly. By means of a videocamera and projector, the paraboloid is projected on the blackboard. Chalk is used to draw the shape of the parabola on the blackboard. Now it is checked that the drawn shape is really paraboloidic by looking for the focal point (F) and course line(c). Our experience is that the positions of this point and line are found quickly by trial and error (until the distances of focal point and course line to the drawn line are equal: see {numref}`Figure {number} <2b2001/figure_1.png>`).
+ The glass beaker is half filled with water. The beaker is submerged in a square reservoir (see Diagram). By means of the electric motor the glass is made rotating. Gradually the liquid climbs the wall of the beaker until it settles itself. The paraboloidic shape can be seen clearly. By means of a videocamera and projector, the paraboloid is projected on the blackboard. Chalk is used to draw the shape of the parabola on the blackboard. Now it is checked that the drawn shape is really paraboloidic by looking for the focal point (F) and course line(c). Our experience is that the positions of this point and line are found quickly by trial and error (until the distances of focal point and course line to the drawn line are equal: see {numref}`Figure {number} <2b2001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 2b2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 2b2001/figure_1.png
----
.
```
## Explanation
- 1. In a rotating reference frame the liquid is in static equilibrium. In this reference frame the sum of the forces acting on the particles in the surface will be perpendicular to that surface. Two forces are acting on such a particle dm: gravity, $F_{1}=d m g$ and the centrifugal force, $F_{2}=d m \omega^{2}$ r. {numref}`Figure {number} <2b2001/figure_2.png>` shows: $\tan \alpha=\frac{d y}{d x}=\frac{\omega^{2} x}{g}$ and from this $y=\frac{1}{2} \frac{\omega^{2} x^{2}}{g}+c$. This is the formula of a parabola.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 2b2001/figure_2.png
----
+ 1. In a rotating reference frame the liquid is in static equilibrium. In this reference frame the sum of the forces acting on the particles in the surface will be perpendicular to that surface. Two forces are acting on such a particle dm: gravity, $F_{1}=d m g$ and the centrifugal force, $F_{2}=d m \omega^{2}$ r. {numref}`Figure {number} <2b2001_figure_2.png>` shows: $\tan \alpha=\frac{d y}{d x}=\frac{\omega^{2} x}{g}$ and from this $y=\frac{1}{2} \frac{\omega^{2} x^{2}}{g}+c$. This is the formula of a parabola.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 2b2001_figure_2.png
+
.
```
-The constant $c$ indicates the position of the lowest point of the rotating liquid. If the $x$ axis in {numref}`Figure {number} <2b2001/figure_1.png>` is located in the surface of the liquid at $\omega=0$, then because of the conservation of mass and the assumed incompressibility of the water, one obtains:
+The constant $c$ indicates the position of the lowest point of the rotating liquid. If the $x$ axis in {numref}`Figure {number} <2b2001_figure_1.png>` is located in the surface of the liquid at $\omega=0$, then because of the conservation of mass and the assumed incompressibility of the water, one obtains:
$\int_{0}^{a} y d x=0$ After integration we find: $c=-\frac{1}{6} \frac{\omega^{2} a^{2}}{g}$
-2. Explaining can also be done from the point of view of hydrostatics (see {numref}`Figure {number} <2b2001/figure_3.png>`).
+2. Explaining can also be done from the point of view of hydrostatics (see {numref}`Figure {number} <2b2001_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 2b2001_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 2b2001/figure_3.png
----
.
```
Pressure in the liquid is a function of $r$ and $z$. When rotating, the forcefield has two components: gravity, $\frac{\partial p}{\partial z}=-\rho g$ and centrifugal, $\frac{\partial p}{\partial r}=\rho \omega^{2} r$. So $d p=-\rho g d z+\rho \omega^{2} r d r$. After integration: $p=-\rho g z+\frac{1}{2} \rho \omega^{2} r^{2}+c$. So surfaces with equal pressure are determined by $z=\frac{\omega^{2}}{2 g} r^{2}+const.$, showing the parabolic relationship.
diff --git a/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2001 Magnus Effect/2C2001.md b/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2001 Magnus Effect/2C2001.md
index d7b59dd4..3dfe5339 100644
--- a/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2001 Magnus Effect/2C2001.md
+++ b/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2001 Magnus Effect/2C2001.md
@@ -7,11 +7,10 @@
* 2C20 (Bernoulli Force)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 2c2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 2c2001_figure_0.png
+
.
```
@@ -26,26 +25,24 @@ name: 2c2001/figure_0.png
## Presentation
The first cylinder is placed on the inclined U-profile that is outside the water basin (see Diagram B). It rolls downwards in a way everybody expects. Mark the place where it hits the table.
-The second cylinder will roll down the inclined U-profile that ends in the water basin. Before doing it, ask the students where this second cylinder will end. (Same way as first cylinder? Or somewhere else?) After their answers this second cylinder is rolled down the incline (see Diagram C) and drops into the water. Instead of following the trajectory of the first cylinder, it moves in a opposite direction (see {numref}`Figure {number} <2c2001/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 2c2001/figure_1.png
----
+The second cylinder will roll down the inclined U-profile that ends in the water basin. Before doing it, ask the students where this second cylinder will end. (Same way as first cylinder? Or somewhere else?) After their answers this second cylinder is rolled down the incline (see Diagram C) and drops into the water. Instead of following the trajectory of the first cylinder, it moves in a opposite direction (see {numref}`Figure {number} <2c2001_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 2c2001_figure_1.png
+
.
```
## Presentation
- The first cylinder is placed on the inclined U-profile that is outside the water basin (see Diagram B). It rolls downwards in a way everybody expects. Mark the place where it hits the table. The second cylinder will roll down the inclined U-profile that ends in the water basin. Before doing it, ask the students where this second cylinder will end. (Same way as first cylinder? Or somewhere else?) After their answers this second cylinder is rolled down the incline (see Diagram C) and drops into the water. Instead of following the trajectory of the first cylinder, it moves in a opposite direction (see {numref}`Figure {number} <2c2001/figure_1.png>`).
+ The first cylinder is placed on the inclined U-profile that is outside the water basin (see Diagram B). It rolls downwards in a way everybody expects. Mark the place where it hits the table. The second cylinder will roll down the inclined U-profile that ends in the water basin. Before doing it, ask the students where this second cylinder will end. (Same way as first cylinder? Or somewhere else?) After their answers this second cylinder is rolled down the incline (see Diagram C) and drops into the water. Instead of following the trajectory of the first cylinder, it moves in a opposite direction (see {numref}`Figure {number} <2c2001_figure_1.png>`).
## Explanation
-A rotating cylinder, moving in a medium (e.g. water) drags that medium round with it. The medium flows in the opposite direction of translation of the cylinder (see {numref}`Figure {number} <2c2001/figure_2.png>`).
+A rotating cylinder, moving in a medium (e.g. water) drags that medium round with it. The medium flows in the opposite direction of translation of the cylinder (see {numref}`Figure {number} <2c2001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 2c2001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 2c2001/figure_2.png
----
.
```
On the right side of the cylinder, the rotation causes the medium to flow slower, while on the other side the medium flows faster. This difference in speed causes a pressure difference; according to Bernoulli's equation: $\Delta p=\frac{1}{2} \rho\left(V_{\text {left }}^{2}-V_{\text {right }}^{2}\right.$. Since $v_{\text {left }}>V_{\text {right }}$, the net lift-force due to $\Delta p$ is pointing to the left and proportional to $\rho\left(v_{\text {left }}^{2}-v_{\text {right }}^{2}\right)$. Also since $v_{\text {left }}=v+\omega r$ and $v_{\text {riaht }}=\nu-\omega r$, $\mathrm{F}_{\text {lift }}$ is proportional to $2 \rho \omega v_{\text {tr }}$. Because the density of water equals $10^{3} \mathrm{~kg} / \mathrm{m}^{3}$, the lift-force is considerable. Therefore the effect of this force is clearly visible as a deviation of a trajectory without rotation.
diff --git a/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2002 Magnus Effect/2C2002.md b/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2002 Magnus Effect/2C2002.md
index e78c95bc..e2caf896 100644
--- a/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2002 Magnus Effect/2C2002.md
+++ b/book/book/2 fluid mechanics/2C dynamics/2C20 Bernoulli Force/2C2002 Magnus Effect/2C2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 2c2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 2c2002_figure_0.png
+
.
```
@@ -22,12 +21,11 @@ name: 2c2002/figure_0.png
## Presentation
-The cloth tape is wrapped around the middle of the cylinder. The cylinder is laid on a table or on the ground, so that the tape will unwind from the bottom. The stick is pulled giving the cylinder linear and spin velocity. The cylinder lifts itself and describes a loop (see {numref}`Figure {number} <2c2002/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 2c2002/figure_1.png
----
+The cloth tape is wrapped around the middle of the cylinder. The cylinder is laid on a table or on the ground, so that the tape will unwind from the bottom. The stick is pulled giving the cylinder linear and spin velocity. The cylinder lifts itself and describes a loop (see {numref}`Figure {number} <2c2002_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 2c2002_figure_1.png
+
.
```
@@ -36,13 +34,12 @@ The rotating cylinder drags the air round with it. The air flows in the opposite
## Remarks
-- In the middle of the cylinder a light piece of wood is stuck to it. Under this piece of wood the cloth tape can be fixed when wrapping it around the cylinder (see {numref}`Figure {number} <2c2002/figure_2.png>`). When the tape is pulled, the end loosens itself easily from the cylinder.
+- In the middle of the cylinder a light piece of wood is stuck to it. Under this piece of wood the cloth tape can be fixed when wrapping it around the cylinder (see {numref}`Figure {number} <2c2002_figure_2.png>`). When the tape is pulled, the end loosens itself easily from the cylinder.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 2c2002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 2c2002/figure_2.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1001 Mathematical Pendulum/3A1001.md b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1001 Mathematical Pendulum/3A1001.md
index e8f71715..3693e375 100644
--- a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1001 Mathematical Pendulum/3A1001.md
+++ b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1001 Mathematical Pendulum/3A1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1001_figure_0.png
+
.
```
@@ -25,11 +24,10 @@ name: 3a1001/figure_0.png
## Presentation
Set up the software to display graphically angular position, angular velocity and angular acceleration of the pendulum. When the pendulum is in its vertical position at rest, we start data collection. We give the pendulum a small amplitude and let it swing. When we have collected about four complete cycles, the data-acquisition is stopped.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1001_figure_1.png
+
.
```
Already at first glance this registered graph shows its sine-shaped appearance. To have a more convincing conclusion the software can apply a mathematical curve-fit to the registered position-graph, to show that a sinusoidal equation "covers" the position-graph very good. So a sine-function describes the behavior (position-time) of this pendulum very good. A second run of the oscillations is registered, but now with a higher amplitude. Clearly can be observed now that the motion is no longer sinusoidal Trying a sine-fit will confirm this (read the chi2-value). Make a third run again with small amplitude and check the differential relationships between 'position', 'velocity' and 'acceleration': e.g.
diff --git a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1002 Mathematical Pendulum/3A1002.md b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1002 Mathematical Pendulum/3A1002.md
index 1fbbe739..fa6464fa 100644
--- a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1002 Mathematical Pendulum/3A1002.md
+++ b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1002 Mathematical Pendulum/3A1002.md
@@ -8,11 +8,10 @@ To show that the period of motion of a simple pendulum depends on the angle the
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1002_figure_0.png
+
.
```
@@ -26,13 +25,12 @@ name: 3a1002/figure_0.png
## Presentation
-The photogate is placed just offset the rest-position of the pendulum. The data-acquisition system is set up in such a way that a graph of periodtimes can be presented. The data-acquisition is started, and by hand the pendulum is given a deflection of almost $180^{\circ}$ and released. When $\theta$ has reached angles smaller than $90^{\circ}$, the data-acquisition is stopped. During the data-acquisition the students observe the graph displayed (see red line in {numref}`Figure {number} <3a1002/figure_1.png>`).
+The photogate is placed just offset the rest-position of the pendulum. The data-acquisition system is set up in such a way that a graph of periodtimes can be presented. The data-acquisition is started, and by hand the pendulum is given a deflection of almost $180^{\circ}$ and released. When $\theta$ has reached angles smaller than $90^{\circ}$, the data-acquisition is stopped. During the data-acquisition the students observe the graph displayed (see red line in {numref}`Figure {number} <3a1002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1002/figure_1.png
----
.
```
@@ -41,7 +39,7 @@ name: 3a1002/figure_1.png
A second run is made, giving the pendulum the smallest deflection possible. After about $10-20$ registrations of $T$ the data-acquisition is stopped. The complete graph can be observed and discussed now.
## Explanation
-The equation that describes the motion of the mass $m$ is given by $a_{x}=\frac{d^{2 s}}{d t^{2}}=-g \sin \theta$ (x-direction along the tangent of the circle; see {numref}`Figure {number} <3a1002/figure_2.png>`A). This is not a simple harmonic motion since $\sin \theta$ is not proportional to $s$.
+The equation that describes the motion of the mass $m$ is given by $a_{x}=\frac{d^{2 s}}{d t^{2}}=-g \sin \theta$ (x-direction along the tangent of the circle; see {numref}`Figure {number} <3a1002_figure_2.png>`A). This is not a simple harmonic motion since $\sin \theta$ is not proportional to $s$.
Only for small amplitude oscillations $\sin \theta \approx \theta=\frac{S}{l}$ and the equation of motion reduces to $\frac{d^{2} s}{d t^{2}}=-\frac{g}{l} s$ This is the differential equation for simple harmonic motion. Then the period is given by $T=2 \pi \sqrt{\frac{l}{g}}$
@@ -52,13 +50,12 @@ For large amplitudes we need $a_{x}=-g \sin \theta$ in stead of $a_{x}=-g \theta
## Remarks
* Also see the demonstration ["Mathematical pendulum (1) - Simple harmonic motion"](../3A1001%20Mathematical%20Pendulum/3A1001.md). With that demonstration the effect on the acceleration a can be observed very well.
* When you observe the pendulum directly by eye it can be seen directly that the period of oscillation is larger at larger angles.
- * The software is setup in such a way that the period is presented after the pendulum has passed three times through the photogate. Every next period is presented after every second passage (see {numref}`Figure {number} <3a1002/figure_2.png>`B).
+ * The software is setup in such a way that the period is presented after the pendulum has passed three times through the photogate. Every next period is presented after every second passage (see {numref}`Figure {number} <3a1002_figure_2.png>`B).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a1002/figure_2.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1003 Mathematical Pendulum/3A1003.md b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1003 Mathematical Pendulum/3A1003.md
index 4063fb08..aea0db5a 100644
--- a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1003 Mathematical Pendulum/3A1003.md
+++ b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1003 Mathematical Pendulum/3A1003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1003_figure_0.png
+
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1004 Chaotic Pendulum/3A1004.md b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1004 Chaotic Pendulum/3A1004.md
index 39f94d1a..91853274 100644
--- a/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1004 Chaotic Pendulum/3A1004.md
+++ b/book/book/3 oscillations and waves/3A osc/3A10 Pendula/3A1004 Chaotic Pendulum/3A1004.md
@@ -9,11 +9,10 @@
* 3A95 (Non-Linear Systems)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1004_figure_0.png
+
.
```
@@ -27,22 +26,20 @@ name: 3a1004/figure_0.png
## Presentation
-The Pendulum is fixed on the shaft of the rotary motion sensor. The rotary motion sensor is fixed to the slide that is driven up and down by a crank mechanism (See Diagram and {numref}`Figure {number} <3a1004/figure_2.png>` 1).
-
-The driven pendulum, see {numref}`Figure {number} <3a1004/figure_1.png>`, is placed on a spot that can be observed by all the students but which can be closed off during the lecture i self. Place it for example just outside the lecture room, so the door can be shut during the lecture, while keeping the monitor image visible to the students
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1004/figure_1.png
----
+The Pendulum is fixed on the shaft of the rotary motion sensor. The rotary motion sensor is fixed to the slide that is driven up and down by a crank mechanism (See Diagram and {numref}`Figure {number} <3a1004_figure_2.png>` 1).
+
+The driven pendulum, see {numref}`Figure {number} <3a1004_figure_1.png>`, is placed on a spot that can be observed by all the students but which can be closed off during the lecture i self. Place it for example just outside the lecture room, so the door can be shut during the lecture, while keeping the monitor image visible to the students
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1004_figure_1.png
+
.
```
-The software is set up to make a Poincaré plot of the angular position and angular velocity, and will be projected in the lecture room with use of the projector. The Poincaré plot will grow during the lecture and after a while the strange chaotic attractor will be displayed. In about 1 hour you will be able to see the contours of the attractor; after an other hour you will have a plot like in {numref}`Figure {number} <3a1004/figure_2.png>`.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a1004/figure_2.png
----
+The software is set up to make a Poincaré plot of the angular position and angular velocity, and will be projected in the lecture room with use of the projector. The Poincaré plot will grow during the lecture and after a while the strange chaotic attractor will be displayed. In about 1 hour you will be able to see the contours of the attractor; after an other hour you will have a plot like in {numref}`Figure {number} <3a1004_figure_2.png>`.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a1004_figure_2.png
+
.
```
@@ -88,22 +85,20 @@ $$
The Parametrically driven pendulum is based on the article, *Unstable periodic orbits in the parametrically excited pendulum, of W. van der Water.*In this article some more friction terms have been added to the equation of motion of the chaotic pendulum, so that result of the simulation and the actual experiment are more like each other.
## Remarks
-- The pendulum is mounted on the Rotary motion sensor which is mounted on the slide and while provide use with the both the angular position and angular velocity (see {numref}`Figure {number} <3a1004/figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3a1004/figure_3.png
----
+- The pendulum is mounted on the Rotary motion sensor which is mounted on the slide and while provide use with the both the angular position and angular velocity (see {numref}`Figure {number} <3a1004_figure_3.png>`).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3a1004_figure_3.png
+
.
```
-- The Photogate is placed on driving wheel and will give use the moment at which we will plot both the angular position and angular velocity of that moment in the Poincaré plot (see {numref}`Figure {number} <3a1004/figure_4.png>`).
+- The Photogate is placed on driving wheel and will give use the moment at which we will plot both the angular position and angular velocity of that moment in the Poincaré plot (see {numref}`Figure {number} <3a1004_figure_4.png>`).
+
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 3a1004_figure_4.png
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 3a1004/figure_4.png
----
.
```
- Test if the driven pendulum keeps his chaotic movement for the period you want to use it, it sometimes ends in a harmonic movement after a while. When this happens try to adjust the driving frequency of the pendulum
diff --git a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1501 Physical Pendulum/3A1501.md b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1501 Physical Pendulum/3A1501.md
index 2cb8eeeb..460ad8b8 100644
--- a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1501 Physical Pendulum/3A1501.md
+++ b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1501 Physical Pendulum/3A1501.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1501/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1501_figure_0.png
+
.
```
@@ -32,7 +31,7 @@ name: 3a1501/figure_0.png
This can be demonstrated when both pendulums are suspended: one at $D$ and the other in one of the extra holes on either side of $D$ (between $A$ and B). When both pendulums start together, after only a few oscillations it is clear that $D$ is the faster pendulum.
## Explanation
-1. For a physical pendulum with mass $m$, oscillating around its suspension in point A, we can write for the period: $T=2 \pi \sqrt{\frac{I_{A}}{m g S}}$ (see {numref}`Figure {number} <3a1501/figure_1.png>` $I_{A}$ being the moment of inertia, and $s$ being the distance between the centre $l_{M}$ of mass and the axis of rotation).
+1. For a physical pendulum with mass $m$, oscillating around its suspension in point A, we can write for the period: $T=2 \pi \sqrt{\frac{I_{A}}{m g S}}$ (see {numref}`Figure {number} <3a1501_figure_1.png>` $I_{A}$ being the moment of inertia, and $s$ being the distance between the centre $l_{M}$ of mass and the axis of rotation).
When the physical pendulum is a long uniform stick of length $l_{F}$ its moment of inertia is $I_{c}=\frac{1}{12} m l_{F}^{2}$ and when it oscillates around a point A a distance $s=\frac{1}{2} l_{f}$ away from $C$, then $I_{A}=\frac{1}{12} m l^{2}+m\left(\frac{1}{2} l\right)^{2}$, so: $I_{A}=\frac{1}{3} m l_{F}^{2}$. The period of the pendulum becomes:
$$T_{F}=2 \pi \sqrt{\frac{\frac{1}{3} m l_{F}^{2}}{\frac{1}{2} m g l_{F}}}=2 \pi \sqrt{\frac{2}{3} \frac{l_{F}}{g}}$$
@@ -43,15 +42,14 @@ name: 3a1501/figure_0.png
$$T_{M}=2 \pi \sqrt{\frac{m l_{M}^{2}}{m g l_{M}}}=2 \pi \sqrt{\frac{l_{M}}{g}}$$
When we want $T_{F}=T_{M}$, then we need that $l_{M}=\frac{2}{3} l_{F}$. This $l_{M}$ is called the reduced length of the physical pendulum.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1501/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1501_figure_1.png
+
.
```
-2. When the physical pendulum is suspended in a point $B$, such that its remaining length is $l_{M}$, then again the period is the same! (See {numref}`Figure {number} <3a1501/figure_2.png>`)
+2. When the physical pendulum is suspended in a point $B$, such that its remaining length is $l_{M}$, then again the period is the same! (See {numref}`Figure {number} <3a1501_figure_2.png>`)
$T=2 \pi \sqrt{\frac{I_{B}}{m g s}}$
@@ -64,11 +62,10 @@ name: 3a1501/figure_1.png
So this pendulum has the same reduced length and the same period as the physical pendulum shown in the first presentation.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a1501/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a1501_figure_2.png
+
.
```
@@ -86,12 +83,11 @@ name: 3a1501/figure_2.png
The length of the stick ( $l_{F}$ ) is 1 meter, so $s$ equals $\frac{1}{\sqrt{12}}=0.289$ meters.
## Remarks
- * In order to give the physical pendulum a length of 1 meter and yet have a hole at the ends of this stick, we have triangularly shaped the ends (see {numref}`Figure {number} <3a1501/figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3a1501/figure_3.png
----
+ * In order to give the physical pendulum a length of 1 meter and yet have a hole at the ends of this stick, we have triangularly shaped the ends (see {numref}`Figure {number} <3a1501_figure_3.png>`).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3a1501_figure_3.png
+
.
```
- The differences in $T$ are small. With $I_{F}=1$ meter, we find: $T_{A}\left(=T_{B}\right)=1.64$ sec. And $T_{D}=1.52 \mathrm{sec}$.
diff --git a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1502 Physical Pendulum/3A1502.md b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1502 Physical Pendulum/3A1502.md
index 5a5d7c1b..2ff73812 100644
--- a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1502 Physical Pendulum/3A1502.md
+++ b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1502 Physical Pendulum/3A1502.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1502/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1502_figure_0.png
+
.
```
@@ -35,25 +34,23 @@ For a physical pendulum the period $T$ is given by: $T=\frac{2 \pi}{\sqrt{g}} \s
Also, $I_{A}=I_{C}+m s^{2}$ (Steiner), so $T$ is constant as long as $s$ is constant.
-The suspension of the three pendulums is chosen such that the distance $s$ is always the same because they are situated on a circle through $\mathrm{C}$ (see {numref}`Figure {number} <3a1502/figure_1.png>`). $s=50 \mathrm{~cm}$.
+The suspension of the three pendulums is chosen such that the distance $s$ is always the same because they are situated on a circle through $\mathrm{C}$ (see {numref}`Figure {number} <3a1502_figure_1.png>`). $s=50 \mathrm{~cm}$.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1502_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1502/figure_1.png
----
.
```
## Remarks
-We also have a suspension as shown in {numref}`Figure {number} <3a1502/figure_2.png>`. Now the suspension point is $0.167 \mathrm{~m}$ away from $\mathrm{C}$ and again $\mathrm{T}$ is the same because now the pendulum swings through the point of its reduced length (see demonstration "Physical pendulum (1)").
+We also have a suspension as shown in {numref}`Figure {number} <3a1502_figure_2.png>`. Now the suspension point is $0.167 \mathrm{~m}$ away from $\mathrm{C}$ and again $\mathrm{T}$ is the same because now the pendulum swings through the point of its reduced length (see demonstration "Physical pendulum (1)").
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a1502/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a1502_figure_2.png
+
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1503 Physical Pendulum/3A1503.md b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1503 Physical Pendulum/3A1503.md
index 05fbe24c..d8923ca4 100644
--- a/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1503 Physical Pendulum/3A1503.md
+++ b/book/book/3 oscillations and waves/3A osc/3A15 Physical Pendula/3A1503 Physical Pendulum/3A1503.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a1503/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a1503_figure_0.png
+
.
```
@@ -33,25 +32,23 @@ Again the same period is measured when $1 / 3$-ring is swinging
## Explanation
- For a physical pendulum, the period $T$ is given by $T=\frac{2 \pi}{\sqrt{g}} \sqrt{\frac{I_{A}}{m s}}$.
- If the pendulum is a complete ring, then $s=R$ (see {numref}`Figure {number} <3a1503/figure_1.png>`), $I_{A}=I_{C}+m R^{2}$ and $I_{c}=m R^{2}$. Then $T=\frac{2 \pi}{\sqrt{g}} \sqrt{2 R}$, so $I_{r}=2 R$.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a1503/figure_1.png
----
+ If the pendulum is a complete ring, then $s=R$ (see {numref}`Figure {number} <3a1503_figure_1.png>`), $I_{A}=I_{C}+m R^{2}$ and $I_{c}=m R^{2}$. Then $T=\frac{2 \pi}{\sqrt{g}} \sqrt{2 R}$, so $I_{r}=2 R$.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a1503_figure_1.png
+
.
```
So a complete ring has the same period as a mathematical pendulum of length 2R.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a1503/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a1503_figure_2.png
+
.
```
-- If the pendulum is part of a complete ring, $I_{O}=m R^{2}$ ({numref}`Figure {number} <3a1503/figure_2.png>`). Also $I_{O}=I_{C}+m(R-$ $s)^{2}$ (C is the center of mass) and $I_{A}=I_{C}+m s^{2}$. It follows that $I_{A}=2 m R s$ and $T=\frac{2 \pi}{\sqrt{g}} \sqrt{2 R}$. So again $I_{r}=2 R$.
+- If the pendulum is part of a complete ring, $I_{O}=m R^{2}$ ({numref}`Figure {number} <3a1503_figure_2.png>`). Also $I_{O}=I_{C}+m(R-$ $s)^{2}$ (C is the center of mass) and $I_{A}=I_{C}+m s^{2}$. It follows that $I_{A}=2 m R s$ and $T=\frac{2 \pi}{\sqrt{g}} \sqrt{2 R}$. So again $I_{r}=2 R$.
## Sources
- Ehrlich, R., Why Toast Lands Jelly-Side Down: Zen and the Art of Physics Demonstrations, pag. 126-127
diff --git a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4001 Mathematical Pendulum/3A4001.md b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4001 Mathematical Pendulum/3A4001.md
index 974353c2..912a7426 100644
--- a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4001 Mathematical Pendulum/3A4001.md
+++ b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4001 Mathematical Pendulum/3A4001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a4001_figure_0.png
+
.
```
@@ -25,11 +24,10 @@ name: 3a4001/figure_0.png
## Presentation
Set up the software to display graphically angular position, angular velocity and angular acceleration of the pendulum. When the pendulum is in its vertical position at rest, we start data collection. We give the pendulum a small amplitude and let it swing. When we have collected about four complete cycles, the data-acquisition is stopped.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a4001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a4001_figure_1.png
+
.
```
Already at first glance this registered graph shows its sine-shaped appearance. To have a more convincing conclusion the software can apply a mathematical curve-fit to the registered position-graph, to show that a sinusoidal equation "covers" the position-graph very good. So a sine-function describes the behavior (position-time) of this pendulum very good. A second run of the oscillations is registered, but now with a higher amplitude. Clearly can be observed now that the motion is no longer sinusoidal Trying a sine-fit will confirm this (read the chi2-value). Make a third run again with small amplitude and check the differential relationships between 'position', 'velocity' and 'acceleration': e.g.
diff --git a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/3A4003.md b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/3A4003.md
index 4526f018..97745a34 100644
--- a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/3A4003.md
+++ b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/3A4003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a4003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a4003_figure_0.png
+
.
```
@@ -27,36 +26,26 @@ name: 3a4003/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/exaFE_NZqcE?si=Qv0CtuOgX3GKw8e7
+```
The spring is hung to a hook and loaded with a mass of $1 \mathrm{~kg}$. When the mass is at rest the sliding marker is positioned at the centre of mass (CM) of the $1 \mathrm{~kg}$ mass (see Diagram). Then the mass is set in oscillatory motion and it can be observed that the mass oscillates around the original position of the CM. Finally, it will end at this position (due to damping). When the system still oscillates, it is brought to a stop. Taking the mass in your hand and positioing it above its rest position, makes it clear to the students that the force on the mass is directed towards the marker. The same is done by positioning the mass below the marker.
he data-acquisition system shows a (still empty) graph of position versus time. Shortly, the functioning of the data-acquisition system is explained to the students (For instance, when moving your hand above the position sensor, the distance to the sensor is monitored on the presented position graph).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a4003/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a4003_figure_1.png
+
.
```
-Data-recording is started and the spring-mass system is set in motion again. When about 5 cycles are registered, the data-recording is stopped and the resulting position graph can be studied (see {numref}`Figure {number} <3a4003/figure_1.png>`A)
+Data-recording is started and the spring-mass system is set in motion again. When about 5 cycles are registered, the data-recording is stopped and the resulting position graph can be studied (see {numref}`Figure {number} <3a4003_figure_1.png>`A)
1. When the mass rises above the marked rest position the first part ($AB$) of the curve shows that it slows down (because $A B$ becomes more and more level). So during $A B$ the force is downwardly directed. From $B$ to $C$ the graph shows that the mass accelerates (because BC becomes steeper all the time). So also during
BC the force is directed downward. CDE can be described in a similar way:
always the force is directed towards the rest-position.
2. The graph suggests very strongly that it has a sine-shape. So by means of the
-software we try a sine-fit (see {numref}`Figure {number} <3a4003/figure_1.png>`B). This fits very well (very low CHI2-
+software we try a sine-fit (see {numref}`Figure {number} <3a4003_figure_1.png>`B). This fits very well (very low CHI2-
value), confirming our "guess".
3. Applying the software we add the graphs of velocity and acceleration. The
differential relationship between these three quantities can be verified now:
diff --git a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/qr_images/qrcode_exaFE_NZqcE_si_Qv0CtuOgX3GKw8e7_.svg b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/qr_images/qrcode_exaFE_NZqcE_si_Qv0CtuOgX3GKw8e7_.svg
new file mode 100644
index 00000000..23f77b2a
--- /dev/null
+++ b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4003 Simple Harmonic/qr_images/qrcode_exaFE_NZqcE_si_Qv0CtuOgX3GKw8e7_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4004 Simple Harmonic/3A4004.md b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4004 Simple Harmonic/3A4004.md
index 8412e88b..14027cc2 100644
--- a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4004 Simple Harmonic/3A4004.md
+++ b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4004 Simple Harmonic/3A4004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a4004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a4004_figure_0.png
+
.
```
@@ -30,15 +29,14 @@ name: 3a4004/figure_0.png
## Presentation
-1. Set up the equipment as shown in the Diagram. On the monitorscreen four graphs are prepared: The springforces $F_{1}$ and $F_{2}$ and the resultant force on the cart $\left(F_{1}-F_{2}\right)$ and the acceleration $a$ of the cart (see {numref}`Figure {number} <3a4004/figure_1.png>`1.
+1. Set up the equipment as shown in the Diagram. On the monitorscreen four graphs are prepared: The springforces $F_{1}$ and $F_{2}$ and the resultant force on the cart $\left(F_{1}-F_{2}\right)$ and the acceleration $a$ of the cart (see {numref}`Figure {number} <3a4004_figure_1.png>`1.
+
+ Collect data while the system is at rest. In the graphs $F_{1}$ and $F_{2}$ show a negative value and $\left(F_{1}-F_{2}\right)$ and $a$ are zero (see the green lines in {numref}`Figure {number} <3a4004_figure_1.png>`). Displace the cart from equilibrium and let it go. Collect data during about 4 complete swings of the system (the red curves in {numref}`Figure {number} <3a4004_figure_1.png>`). Make a sine curve-fit for the graph that displays the acceleration, to show that the motion is really harmonic.
- Collect data while the system is at rest. In the graphs $F_{1}$ and $F_{2}$ show a negative value and $\left(F_{1}-F_{2}\right)$ and $a$ are zero (see the green lines in {numref}`Figure {number} <3a4004/figure_1.png>`). Displace the cart from equilibrium and let it go. Collect data during about 4 complete swings of the system (the red curves in {numref}`Figure {number} <3a4004/figure_1.png>`). Make a sine curve-fit for the graph that displays the acceleration, to show that the motion is really harmonic.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a4004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a4004/figure_1.png
----
.
```
@@ -51,7 +49,7 @@ name: 3a4004/figure_1.png
2. Analysis shows that for SHM of a spring-mass system $\omega=\sqrt{\frac{k}{m}}$. So increasing the mass fourfold means a reduction of $\omega$ by a factor 2.
## Remarks
-- The graphs of $F_{1}-F_{2}$ and acceleration show directly the linear relationship between $F$ and $a$. So in this demonstration Newton's second law is visible directly. The values of maximum $\left(F_{1}-F_{2}\right)$ and maximum $a$, shown in the "statistics box" of the display (see {numref}`Figure {number} <3a4004/figure_1.png>`) give directly the value of $m$ : $m=\frac{F_{1}-F_{2}}{a}$.
+- The graphs of $F_{1}-F_{2}$ and acceleration show directly the linear relationship between $F$ and $a$. So in this demonstration Newton's second law is visible directly. The values of maximum $\left(F_{1}-F_{2}\right)$ and maximum $a$, shown in the "statistics box" of the display (see {numref}`Figure {number} <3a4004_figure_1.png>`) give directly the value of $m$ : $m=\frac{F_{1}-F_{2}}{a}$.
## Sources
diff --git a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4005 Simple Harmonic/3A4005.md b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4005 Simple Harmonic/3A4005.md
index 349e565e..cf6ac4e4 100644
--- a/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4005 Simple Harmonic/3A4005.md
+++ b/book/book/3 oscillations and waves/3A osc/3A40 Simple/3A4005 Simple Harmonic/3A4005.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a4005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a4005_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ name: 3a4005/figure_0.png
- One spring is hung to a hook and loaded with $1 \mathrm{~kg}$. The extension is observed and the spring constant $k$ can be determined.
-- The software is set up to display a graph of position-time. By hand the mass is displaced more vertically and released. Now the mass oscillates: a linear translational motion confined to the vertical direction. After some time data collection is started. We collect data during around 10 seconds. It can be observed that the position-time graph has a sinusoidal shape. To verify this, we select a little more than one cycle displayed on the screen and then have the software make a sine-fit. A black-lined sine is drawn in the red-colored collected data and the fit is unmistakable correct (within certain limits, see {numref}`Figure {number} <3a4005/figure_1.png>`: $\mathrm{CHI}^{2}=0.002254$, the smaller this number, the better the agreement between collected data and the mathematical sine).
+- The software is set up to display a graph of position-time. By hand the mass is displaced more vertically and released. Now the mass oscillates: a linear translational motion confined to the vertical direction. After some time data collection is started. We collect data during around 10 seconds. It can be observed that the position-time graph has a sinusoidal shape. To verify this, we select a little more than one cycle displayed on the screen and then have the software make a sine-fit. A black-lined sine is drawn in the red-colored collected data and the fit is unmistakable correct (within certain limits, see {numref}`Figure {number} <3a4005_figure_1.png>`: $\mathrm{CHI}^{2}=0.002254$, the smaller this number, the better the agreement between collected data and the mathematical sine).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a4005_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a4005/figure_1.png
----
.
```
@@ -51,24 +49,22 @@ name: 3a4005/figure_1.png
## Explanation
1. A simple mass-spring system oscillates with a frequency $\omega=\sqrt{\frac{k}{m}}$. So doubling the mass will lower the frequency by a factor $\frac{1}{\sqrt{2}}$.
-2. When two springs are connected in series, this combined spring will have a "new" spring constant of $k_{3}=\frac{F}{x_{1}+x_{2}}$ (see {numref}`Figure {number} <3a4005/figure_2.png>`). F acts everywhere in the combined system, so $x_{1}=F / k_{1}$ and $x_{2}=F / k_{2}$. This yields $k_{3}=\frac{k_{1} k_{2}}{k_{1}+k_{2}}$.
+2. When two springs are connected in series, this combined spring will have a "new" spring constant of $k_{3}=\frac{F}{x_{1}+x_{2}}$ (see {numref}`Figure {number} <3a4005_figure_2.png>`). F acts everywhere in the combined system, so $x_{1}=F / k_{1}$ and $x_{2}=F / k_{2}$. This yields $k_{3}=\frac{k_{1} k_{2}}{k_{1}+k_{2}}$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a4005/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a4005_figure_2.png
+
.
```
In our demonstration $k_{1}=k_{2}(=k)$, so $k_{3}=1 / 2 k$. The frequency will change according to $\omega=\sqrt{\frac{k}{m}}$. So a system with two springs in series and two masses added to it will have half the frequency of one mass suspended to one spring.
-3. When two springs are connected parallel: $k_{1} x_{1}+k_{2} x_{2}=F=k_{3} x$. $k_{3}=F / x$ (see {numref}`Figure {number} <3a4005/figure_3.png>`), so $k_{3}=\frac{k_{1} x_{1}+k_{2} x_{2}}{x}$.
+3. When two springs are connected parallel: $k_{1} x_{1}+k_{2} x_{2}=F=k_{3} x$. $k_{3}=F / x$ (see {numref}`Figure {number} <3a4005_figure_3.png>`), so $k_{3}=\frac{k_{1} x_{1}+k_{2} x_{2}}{x}$.
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3a4005_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3a4005/figure_3.png
----
.
```
When the system is made in such a way that $x_{1}=x_{2}$, then $x_{1}=x_{2}=x$ and $k_{3}=k_{1}+k_{2}$. So in our demonstration $k_{3}=2 k$. So a system with two springs in parallel and two masses added to it will oscillate with the same frequency as when one mass is suspended to one spring. The measured $\omega$ s can be verified now.
diff --git a/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5001 Damped Harmonic/3A5001.md b/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5001 Damped Harmonic/3A5001.md
index fbd34507..618d92b7 100644
--- a/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5001 Damped Harmonic/3A5001.md
+++ b/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5001 Damped Harmonic/3A5001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a5001_figure_0.png
+
.
```
@@ -34,13 +33,12 @@ name: 3a5001/figure_0.png
## Presentation
-Mount the cart with motion sensor and the mass of $.5 \mathrm{~kg}$ between the two springs that are attached to the end-stops of the track. Position the reflecting screen, needed for the motion sensor, at the end of the track. Place the photo-gate in such a position that the laser-beam just not touches the cart. The data-acquisition system is set so that collection of data starts as soon as the cart crosses the laser-beam. (See Diagram.) Prepare a graph to display position versus time (see {numref}`Figure {number} <3a5001/figure_1.png>`)
+Mount the cart with motion sensor and the mass of $.5 \mathrm{~kg}$ between the two springs that are attached to the end-stops of the track. Position the reflecting screen, needed for the motion sensor, at the end of the track. Place the photo-gate in such a position that the laser-beam just not touches the cart. The data-acquisition system is set so that collection of data starts as soon as the cart crosses the laser-beam. (See Diagram.) Prepare a graph to display position versus time (see {numref}`Figure {number} <3a5001_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a5001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a5001/figure_1.png
----
.
```
@@ -48,14 +46,14 @@ Give the cart a deflection, start the data-acquisition system and let the cart g
Remove the mass of $.5 \mathrm{~kg}$. Show by means of a pair of scales that the $50 \times 50 \mathrm{~cm}^{2}$ screen has also a mass of $.5 \mathrm{~kg}$. Mount the screen on the cart. Give the cart the same deflection as in the foregoing run, start the data-acquisition system and let the cart go. Again collect data during 20 sec.
-The two graphs of position can be studied and discussed now (see {numref}`Figure {number} <3a5001/figure_1.png>`). Clearly can be observed that the screen on the cart introduces more damping to the oscillating system. Also can be seen that damping reduces the frequency of the oscillation.
+The two graphs of position can be studied and discussed now (see {numref}`Figure {number} <3a5001_figure_1.png>`). Clearly can be observed that the screen on the cart introduces more damping to the oscillating system. Also can be seen that damping reduces the frequency of the oscillation.
## Explanation
Damping happens due to resistance forces dissipating energy. Such forces can be described assuming that the magnitude of the resistance force is related to the speed of the body as $F=-b v^{n}$ ( $n$ is a number between 1 and 2; $b$ is the damping coefficient).
For many situations $n$ is given the extreme value of $n=1$, making the resistance force equal to $F=-b v$. Then for such a damped oscillator the position of mass $m$ can be expressed by $x=e^{-\alpha t} A \sin (\omega t+\varphi), \alpha=\frac{b}{2 m}$. Increasing $b$ (mounting the $50 \times 50 \mathrm{~cm}^{2}$-screen on the cart) means increasing $\alpha$ and so $e^{-\alpha t}$ decreases faster with time.
-The angular frequency of a damped system equals $\omega=\sqrt{\omega_{0}^{2}-\frac{b^{2}}{4 m^{2}}}, \omega_{o}$ being the frequency in the absence of damping. So increasing $b$ means decreasing $\omega$. Comparing the period of the oscillations of the green line in {numref}`Figure {number} <3a5001/figure_1.png>` with those of the red line, shows this clearly.
+The angular frequency of a damped system equals $\omega=\sqrt{\omega_{0}^{2}-\frac{b^{2}}{4 m^{2}}}, \omega_{o}$ being the frequency in the absence of damping. So increasing $b$ means decreasing $\omega$. Comparing the period of the oscillations of the green line in {numref}`Figure {number} <3a5001_figure_1.png>` with those of the red line, shows this clearly.
## Sources
* Alonso, M/Finn, E. J., Fundamentele Natuurkunde, part 1, Mechanica, pag. 297-299
diff --git a/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5002 Damped Galvanometer/3A5002.md b/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5002 Damped Galvanometer/3A5002.md
index 5993f174..7b23ed20 100644
--- a/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5002 Damped Galvanometer/3A5002.md
+++ b/book/book/3 oscillations and waves/3A osc/3A50 Damped/3A5002 Damped Galvanometer/3A5002.md
@@ -9,11 +9,10 @@
* 5K10 (Induced Currents and Forces)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a5002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a5002_figure_0.png
+
.
```
@@ -23,16 +22,15 @@ name: 3a5002/figure_0.png
* Resistance-box ($10\mathrm{~k\Omega}$)
* Laser
* Stopwatch
- * (Torsionwire model, see {numref}`Figure {number} <3a5002/figure_2.png>`).
+ * (Torsionwire model, see {numref}`Figure {number} <3a5002_figure_2.png>`).
## Presentation
-Galvanometer and laser are positioned in such a way that, in the neutral position of the galvanometer, the reflected laser beam is projected on the blackboard behind the laser (see {numref}`Figure {number} <3a5002/figure_1.png>`). This neutral position is chalk-marked on the blackboard.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a5002/figure_1.png
----
+Galvanometer and laser are positioned in such a way that, in the neutral position of the galvanometer, the reflected laser beam is projected on the blackboard behind the laser (see {numref}`Figure {number} <3a5002_figure_1.png>`). This neutral position is chalk-marked on the blackboard.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a5002_figure_1.png
+
.
```
@@ -80,13 +78,12 @@ Critical damping when $r^{2}=4 I \kappa$. Then equilibrium is reached in the sho
$\omega^{2}=\frac{\kappa}{I}-\left(\frac{r}{2 I}\right)^{2}$ shows that $\omega$ has a lower value than in the undamped situation. $\omega$
## Remarks
-- When the students have not seen a torsionwire system before, such a system is shortly explained to them using a large scale model (a piece of rope, having a rectangular sheet of metal and a small coil, taped to it. See {numref}`Figure {number} <3a5002/figure_2.png>`.)
+- When the students have not seen a torsionwire system before, such a system is shortly explained to them using a large scale model (a piece of rope, having a rectangular sheet of metal and a small coil, taped to it. See {numref}`Figure {number} <3a5002_figure_2.png>`.)
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a5002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a5002/figure_2.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9501 Fakir/3A9501.md b/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9501 Fakir/3A9501.md
index 550ebdc2..e0566fda 100644
--- a/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9501 Fakir/3A9501.md
+++ b/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9501 Fakir/3A9501.md
@@ -12,11 +12,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a9501/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a9501_figure_0.png
+
.
```
diff --git a/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9502 Chaotic Pendulum/3A9502.md b/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9502 Chaotic Pendulum/3A9502.md
index ab7e437d..878e529e 100644
--- a/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9502 Chaotic Pendulum/3A9502.md
+++ b/book/book/3 oscillations and waves/3A osc/3A95 Non Linear/3A9502 Chaotic Pendulum/3A9502.md
@@ -8,11 +8,10 @@
* 3A10 (Pendula) 3A95 (Non-Linear Systems)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3a9502/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3a9502_figure_0.png
+
.
```
@@ -26,23 +25,21 @@ name: 3a9502/figure_0.png
## Presentation
-The Pendulum is fixed on the shaft of the rotary motion sensor. The rotary motion sensor is fixed to the slide that is driven up and down by a crank mechanism (See Diagram and {numref}`Figure {number} <3a9502/figure_2.png>` 1).
-
-The driven pendulum, see {numref}`Figure {number} <3a9502/figure_1.png>`, is placed on a spot that can be observed by all the students but which can be closed off during the lecture i self. Place it for example just outside the lecture room, so the door can be shut during the lecture, while keeping the monitor image visible to the students
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3a9502/figure_1.png
----
+The Pendulum is fixed on the shaft of the rotary motion sensor. The rotary motion sensor is fixed to the slide that is driven up and down by a crank mechanism (See Diagram and {numref}`Figure {number} <3a9502_figure_2.png>` 1).
+
+The driven pendulum, see {numref}`Figure {number} <3a9502_figure_1.png>`, is placed on a spot that can be observed by all the students but which can be closed off during the lecture i self. Place it for example just outside the lecture room, so the door can be shut during the lecture, while keeping the monitor image visible to the students
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3a9502_figure_1.png
+
.
```
-The software is set up to make a Poincaré plot of the angular position and angular velocity, and will be projected in the lecture room with use of the projector. The Poincaré plot will grow during the lecture and after a while the strange chaotic attractor will be displayed. In about 1 hour you will be able to see the contours of the attractor; after an other hour you will have a plot like in {numref}`Figure {number} <3a9502/figure_2.png>`.
+The software is set up to make a Poincaré plot of the angular position and angular velocity, and will be projected in the lecture room with use of the projector. The Poincaré plot will grow during the lecture and after a while the strange chaotic attractor will be displayed. In about 1 hour you will be able to see the contours of the attractor; after an other hour you will have a plot like in {numref}`Figure {number} <3a9502_figure_2.png>`.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3a9502_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3a9502/figure_2.png
----
.
```
@@ -88,22 +85,20 @@ $$
The Parametrically driven pendulum is based on the article, *Unstable periodic orbits in the parametrically excited pendulum, of W. van der Water.*In this article some more friction terms have been added to the equation of motion of the chaotic pendulum, so that result of the simulation and the actual experiment are more like each other.
## Remarks
-- The pendulum is mounted on the Rotary motion sensor which is mounted on the slide and while provide use with the both the angular position and angular velocity (see {numref}`Figure {number} <3a9502/figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3a9502/figure_3.png
----
+- The pendulum is mounted on the Rotary motion sensor which is mounted on the slide and while provide use with the both the angular position and angular velocity (see {numref}`Figure {number} <3a9502_figure_3.png>`).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3a9502_figure_3.png
+
.
```
-- The Photogate is placed on driving wheel and will give use the moment at which we will plot both the angular position and angular velocity of that moment in the Poincaré plot (see {numref}`Figure {number} <3a9502/figure_4.png>`).
+- The Photogate is placed on driving wheel and will give use the moment at which we will plot both the angular position and angular velocity of that moment in the Poincaré plot (see {numref}`Figure {number} <3a9502_figure_4.png>`).
+
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 3a9502_figure_4.png
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 3a9502/figure_4.png
----
.
```
- Test if the driven pendulum keeps his chaotic movement for the period you want to use it, it sometimes ends in a harmonic movement after a while. When this happens try to adjust the driving frequency of the pendulum
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1001 Reflections of Transverse Pulses/3B1001.md b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1001 Reflections of Transverse Pulses/3B1001.md
index 8835e311..e015b3ba 100644
--- a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1001 Reflections of Transverse Pulses/3B1001.md
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1001 Reflections of Transverse Pulses/3B1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b1001_figure_0.png
+
.
```
@@ -36,13 +35,12 @@ Also applying the energy-concept can strengthen the insight in the shown phenome
When the end of the wave demonstrator is fixed, a convenient model to explain the phase change by $180^\circ$ is that the end must be a node, so at any moment the sum of the arriving pulse and the reflected one must add to zero.
## Remarks
-- Before showing the demonstration it is advised to practice with it, because it needs some 'skill' to produce a sharp disturbance in the upward direction without overshoot in the downward direction. And such a disturbance is needed for a good demonstration. A good way to do this is that with one hand you produce the disturbance and the other hand you hold in the zero-deflection position as a reference you should not pass (see {numref}`Figure {number} <3b1001/figure_1.png>`).
+- Before showing the demonstration it is advised to practice with it, because it needs some 'skill' to produce a sharp disturbance in the upward direction without overshoot in the downward direction. And such a disturbance is needed for a good demonstration. A good way to do this is that with one hand you produce the disturbance and the other hand you hold in the zero-deflection position as a reference you should not pass (see {numref}`Figure {number} <3b1001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b1001/figure_1.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/3B1002.md b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/3B1002.md
index e4ffa55d..6e85b680 100644
--- a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/3B1002.md
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/3B1002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b1002_figure_0.png
+
.
```
@@ -32,17 +31,8 @@ name: 3b1002/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/YQAKQVE3gqk?si=MBSepn730SyqXOce
+```
The piece of rope is knotted to the rubber hose. The loose ends of rubber hose and rope are blocked by the L-section and heavy weight (see Diagram). The demonstration is set up in such a way that the instructor holds the rubber hose: One leg of the assembly is completely a rubber hose, the other leg: rubber hose tied to rope (piece of rope about $70 \%$ of the total length of the leg).
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/qr_images/qrcode_YQAKQVE3gqk_si_MBSepn730SyqXOce_.svg b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/qr_images/qrcode_YQAKQVE3gqk_si_MBSepn730SyqXOce_.svg
new file mode 100644
index 00000000..7119f269
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1002 Speed of a Single Pulse on Different Strings/qr_images/qrcode_YQAKQVE3gqk_si_MBSepn730SyqXOce_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1003 Reflections of Transverse Pulses/3B1003.md b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1003 Reflections of Transverse Pulses/3B1003.md
index 6fe36059..389a28c7 100644
--- a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1003 Reflections of Transverse Pulses/3B1003.md
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1003 Reflections of Transverse Pulses/3B1003.md
@@ -7,18 +7,17 @@
* 3B10 (Transverse Pulses and Waves)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b1003_figure_0.png
+
.
```
## Equipment
- Heavy rubber hose ( $l=10 \mathrm{~m}$ ).
-- Heavy weight ( $m=25 \mathrm{~kg}$; see the construction in {numref}`Figure {number} <3b1003/figure_1.png>` and {numref}`Figure {number} <3b1003/figure_2.png>`).
+- Heavy weight ( $m=25 \mathrm{~kg}$; see the construction in {numref}`Figure {number} <3b1003_figure_1.png>` and {numref}`Figure {number} <3b1003_figure_2.png>`).
- Tape
- Oil.
- Camera
@@ -26,25 +25,23 @@ name: 3b1003/figure_0.png
## Presentation
-Lay the long piece of hose in a straight line on the floor in front of the lecture room. On the floor, this straight line is marked by tape (see Diagram). -At one end the hose is fixed (see {numref}`Figure {number} <3b1003/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b1003/figure_1.png
----
+Lay the long piece of hose in a straight line on the floor in front of the lecture room. On the floor, this straight line is marked by tape (see Diagram). -At one end the hose is fixed (see {numref}`Figure {number} <3b1003_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b1003_figure_1.png
+
.
```
Reflections of transverse pulses (1)
Give, by hand, the free end of the hose a sharp horizontal displacement. A crest travels along the hose (see the pictures of Diagram A) and reflects at the fixed end as a trough.
--Next the hose is fixed as a loose end (see {numref}`Figure {number} <3b1003/figure_2.png>`).
+-Next the hose is fixed as a loose end (see {numref}`Figure {number} <3b1003_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3b1003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3b1003/figure_2.png
----
.
```
The end of the hose can now freely move sideways; it is a so-called "free end". (We apply some oil on the metal shaft to reduce friction.) The demonstration is repeated and it can be observed that a crest traveling along the hose now returns as a crest (see the pictures of Diagram B).
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1004 Speed of a Single Pulse on Different Strings/3B1004.md b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1004 Speed of a Single Pulse on Different Strings/3B1004.md
index 4442b638..f7f89b17 100644
--- a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1004 Speed of a Single Pulse on Different Strings/3B1004.md
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1004 Speed of a Single Pulse on Different Strings/3B1004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b1004_figure_0.png
+
.
```
@@ -29,12 +28,11 @@ name: 3b1004/figure_0.png
## Presentation
-The demonstration is set up as shown in Diagram and {numref}`Figure {number} <3b1004/figure_1.png>`.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b1004/figure_1.png
----
+The demonstration is set up as shown in Diagram and {numref}`Figure {number} <3b1004_figure_1.png>`.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b1004_figure_1.png
+
.
```
@@ -46,7 +44,7 @@ When demonstrating the four-folded rope, you can use your voice as a stable time
The velocity of a wave along a rope is $v=\sqrt{\frac{T}{\mu}}, T$ being the tension in the rope and $\mu$ its mass per unit length. Both parts have the same tension (both are loaded with $1 \mathrm{~kg}$ ), so the difference in the velocity of propagation is explained by the difference in $\mu$. $\mu$ being four times higher in the fourfolded rope makes $\nu$ two times lower.
## Remarks
-- As presented in the picture of the Diagram, to the audience it is hard for them to see the crest traveling along the rope. Observation along the rope presents a much better view. We use the camera in such a position to make the traveling crest clearly visible (see {numref}`Figure {number} <3b1004/figure_1.png>` and Diagram).
+- As presented in the picture of the Diagram, to the audience it is hard for them to see the crest traveling along the rope. Observation along the rope presents a much better view. We use the camera in such a position to make the traveling crest clearly visible (see {numref}`Figure {number} <3b1004_figure_1.png>` and Diagram).
- The "sharp blow" should be given horizontally.
diff --git a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1005 Transverse Traveling Wave/3B1005.md b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1005 Transverse Traveling Wave/3B1005.md
index 02fb0026..24a067e0 100644
--- a/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1005 Transverse Traveling Wave/3B1005.md
+++ b/book/book/3 oscillations and waves/3B wave/3B10 Transverse/3B1005 Transverse Traveling Wave/3B1005.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b1005/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b1005_figure_0.png
+
.
```
diff --git a/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/3B2001.md b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/3B2001.md
index d577035d..ed21611b 100644
--- a/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/3B2001.md
+++ b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/3B2001.md
@@ -7,11 +7,10 @@
* 3B20 (Longitudinal Pulses and Waves)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2001_figure_0.png
+
.
```
@@ -33,26 +32,16 @@ The equipment is set up as shown in Diagram. The power supply is set at around $
### Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/5k6pqTMEdKg?si=oNCvgrScaGwPgZxO
+```
Just to explain the operation of the set-up, the pipe is hit by hand and the oscilloscope displays the noise registered by the microphone and oscilloscope. Also the pulsing of the speaker is made audible to the students by switching the power supply to the speaker on and off a couple of times.
-Next, the speaker is placed in front of the pipe and the cap is placed on the end of the pipe. The switch to the speaker is operated and after the pulse, the oscilloscope shows what is happening (see {numref}`Figure {number} <3b2001/figure_1.png>`). 'A' occurs after the sound pulse has left the speaker and has travelled halfway down the pipe. The second pulse (B) is the microphone's registration of the sound pulse after reflection at the end cap. This reflection mirrors the original pulse quite well.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2001/figure_1.png
----
+Next, the speaker is placed in front of the pipe and the cap is placed on the end of the pipe. The switch to the speaker is operated and after the pulse, the oscilloscope shows what is happening (see {numref}`Figure {number} <3b2001_figure_1.png>`). 'A' occurs after the sound pulse has left the speaker and has travelled halfway down the pipe. The second pulse (B) is the microphone's registration of the sound pulse after reflection at the end cap. This reflection mirrors the original pulse quite well.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2001_figure_1.png
+
.
```
@@ -61,24 +50,14 @@ Two observations are made:
- The pulse travels 4 meters between pulse $A$ and $B$. We observe around 6 divisions between pulse $\mathrm{A}$ and $\mathrm{B}$; with $2 \mathrm{msec} / \mathrm{DIV}$ at the horizontal time base, we get a pulse speed of: $v=4 \mathrm{~m} / 6 \times 2 \mathrm{msec}=333 \mathrm{~m} / \mathrm{sec}$.
- The reflected pulse B has the same phase as pulse A.
-
-
-
-
-
-
-The cap at the end of the pipe is removed and by operating the switch again a sound pulse is made traveling down the tube. The scope image registers what is happening now (see {numref}`Figure {number} <3b2001/figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3b2001/figure_2.png
----
+```{iframe} https://www.youtube.com/embed/LF3kxiy4UBI?si=oX-Pm0N3wQh7UDjX
+```
+
+The cap at the end of the pipe is removed and by operating the switch again a sound pulse is made traveling down the tube. The scope image registers what is happening now (see {numref}`Figure {number} <3b2001_figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3b2001_figure_2.png
+
.
```
Again the reflected pulse mirrors the first pulse, but, as can be seen, its phase is inverted now!
@@ -86,15 +65,14 @@ Again the reflected pulse mirrors the first pulse, but, as can be seen, its phas
A reference is made to the demonstrations [Reflections of transverse pulses](/book/3%20oscillations%20and%20waves/3B%20wave/3B10%20Transverse/3B1001%20Reflections%20of%20Transverse%20Pulses/3B1001.md) and [Reflections of transverse pulses](/book/3%20oscillations%20and%20waves/3B%20wave/3B10%20Transverse/3B1003%20Reflections%20of%20Transverse%20Pulses/3B1003.md).
## Explanation
- One way to explain the mechanism of reflection is by means of a very simplified 1D-billiard ball model of the air column (see {numref}`Figure {number} <3b2001/figure_3.png>` A and B): Five balls in a row represent the air column in the pipe; the separation between the balls indicates the pressure (the microphone has an output proportional to pressure-increase/decrease).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3b2001/figure_3.png
----
+ One way to explain the mechanism of reflection is by means of a very simplified 1D-billiard ball model of the air column (see {numref}`Figure {number} <3b2001_figure_3.png>` A and B): Five balls in a row represent the air column in the pipe; the separation between the balls indicates the pressure (the microphone has an output proportional to pressure-increase/decrease).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3b2001_figure_3.png
+
.
```
-{numref}`Figure {number} <3b2001/figure_3.png>`A shows how a pulse fed to the speaker drives its cone to the right and the subsequent "frames" show how in the air column an increased pressure region (red) is followed by a decreasing pressure region (blue). The frames make also clear that after reflection the sequence of higher - and lower pressure remains the same. When the end cap is removed, the opening of the pipe is a free end (see {numref}`Figure {number} <3b2001/figure_3.png>`B). When the original pulse arrives at the last billiard ball, it will swing outward and a pressure drop is created at the end of the pipe, pulling billiard balls inside the pipe also outward (see frame 7,8,9 and 10). A pressure through displaces itself to the left and the lower pressure region is now ahead of the higher pressure region.
+{numref}`Figure {number} <3b2001_figure_3.png>`A shows how a pulse fed to the speaker drives its cone to the right and the subsequent "frames" show how in the air column an increased pressure region (red) is followed by a decreasing pressure region (blue). The frames make also clear that after reflection the sequence of higher - and lower pressure remains the same. When the end cap is removed, the opening of the pipe is a free end (see {numref}`Figure {number} <3b2001_figure_3.png>`B). When the original pulse arrives at the last billiard ball, it will swing outward and a pressure drop is created at the end of the pipe, pulling billiard balls inside the pipe also outward (see frame 7,8,9 and 10). A pressure through displaces itself to the left and the lower pressure region is now ahead of the higher pressure region.
When comparing this demonstration of reflecting sound pulses with reflections of pulses on ropes (see the demonstrations [Reflections of transverse pulses](/book/3%20oscillations%20and%20waves/3B%20wave/3B10%20Transverse/3B1001%20Reflections%20of%20Transverse%20Pulses/3B1001.md) and [Reflections of transverse pulses](/book/3%20oscillations%20and%20waves/3B%20wave/3B10%20Transverse/3B1003%20Reflections%20of%20Transverse%20Pulses/3B1003.md)), confusion may rise. Most students will see the cap as a fixed end. But it should be realized that in this sound demonstration the microphone reacts to pressure! That is what we see on the display of the oscilloscope, and not displacement! When a sound pulse hits the cap, this closed end corresponds to a pressure antinode, that is, a point of maximum pressure variation (to air displacement the cap is a node). So, when compared with the observed reflections on the ends of ropes, the cap (being a point of maximum pressure variation) should be compared with a rope that has a free end (being a point of maximum rope displacement). In the same way the situation of an open pipe is a pressure node; the pressure at this end remains at atmospheric pressure. Compared with a rope this corresponds with a fixed end.
diff --git a/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_5k6pqTMEdKg_si_oNCvgrScaGwPgZxO_.svg b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_5k6pqTMEdKg_si_oNCvgrScaGwPgZxO_.svg
new file mode 100644
index 00000000..a461e3e9
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_5k6pqTMEdKg_si_oNCvgrScaGwPgZxO_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_LF3kxiy4UBI_si_oX_Pm0N3wQh7UDjX_.svg b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_LF3kxiy4UBI_si_oX_Pm0N3wQh7UDjX_.svg
new file mode 100644
index 00000000..70f9f897
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B20 Longitudinal/3B2001 Reflected Sound Pulses/qr_images/qrcode_LF3kxiy4UBI_si_oX_Pm0N3wQh7UDjX_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2201 deBroglie Applied to Bohr/3B2201.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2201 deBroglie Applied to Bohr/3B2201.md
index f1c6fcf0..8ae8b675 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2201 deBroglie Applied to Bohr/3B2201.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2201 deBroglie Applied to Bohr/3B2201.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2201/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2201_figure_0.png
+
.
```
@@ -36,21 +35,20 @@ name: 3b2201/figure_0.png
The wire loop is fitted to the mechanical wave driver shaft. The wave driver is connected to the signal generator. The image of wire loop and display of the frequency of the driving generator is projected (see Diagram).
Start at low frequency (around $5 \mathrm{~Hz}$ ) and low amplitude, making the loop starting to vibrate. Increase the frequency to see various modes of standing waves in the circular loop. (At higher frequencies the amplitude of the signal generator has to increase to obtain visible amplitude in the oscillating wire loop.) We observe:
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2201/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2201_figure_1.png
+
.
```
- 2 nodes and anti-nodes at $14 \mathrm{~Hz}$;
-- 3 nodes and anti-nodes at $23 \mathrm{~Hz}$ (very large amplitude) (see {numref}`Figure {number} <3b2201/figure_1.png>`A);
+- 3 nodes and anti-nodes at $23 \mathrm{~Hz}$ (very large amplitude) (see {numref}`Figure {number} <3b2201_figure_1.png>`A);
- 4 nodes and anti-nodes at $30 \mathrm{~Hz}$;
-- 5 nodes and anti-nodes at $76 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201/figure_1.png>`B);
+- 5 nodes and anti-nodes at $76 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201_figure_1.png>`B);
-- 7 nodes and anti-nodes at $163 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201/figure_1.png>`C);
+- 7 nodes and anti-nodes at $163 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201_figure_1.png>`C);
-- 9 nodes and anti-nodes at $273 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201/figure_1.png>`D);
+- 9 nodes and anti-nodes at $273 \mathrm{~Hz}$ (see {numref}`Figure {number} <3b2201_figure_1.png>`D);
-11 nodes and anti-nodes at $398 \mathrm{~Hz}$ (this last one is not so good visible to a larger audience due to its low amplitude).
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2202 Handheld Standing Waves/3B2202.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2202 Handheld Standing Waves/3B2202.md
index 2f9e0c3c..827ac349 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2202 Handheld Standing Waves/3B2202.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2202 Handheld Standing Waves/3B2202.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2202/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2202_figure_0.png
+
.
```
@@ -25,7 +24,7 @@ name: 3b2202/figure_0.png
## Presentation
-The white string is fixed to the standing-wave generator (see the first topic in "Remarks" for a description of the standing-wave generator). Hold the standing-wave generator by the string close to the device.Slowly increase the amount of string by which the generator is suspended and you will see standing waves at specific lengths of the string(see {numref}`Figure {number} <3b2202/figure_1.png>`).
+The white string is fixed to the standing-wave generator (see the first topic in "Remarks" for a description of the standing-wave generator). Hold the standing-wave generator by the string close to the device.Slowly increase the amount of string by which the generator is suspended and you will see standing waves at specific lengths of the string(see {numref}`Figure {number} <3b2202_figure_1.png>`).
## Explanation
@@ -38,13 +37,12 @@ Doubling the length reduces the fundamental frequency of the string by a factor
## Remarks
- To make the generator vibrate, a dowel is fixed eccentrically to the shaft of the motor. We obtain lower frequencies by clipping a small clamp to the dowel (see Diagram). Shifting the clamp changes the frequency.
- Be sure that the clamp is fixed strong enough so it will not fly away when the device is vibrating.
-- In order not become entangled in the string while demonstrating, the free end of the string hangs down across the shoulder of the demonstrator (see {numref}`Figure {number} <3b2202/figure_1.png>`)
+- In order not become entangled in the string while demonstrating, the free end of the string hangs down across the shoulder of the demonstrator (see {numref}`Figure {number} <3b2202_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2202_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2202/figure_1.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2203 Kundts Tube/3B2203.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2203 Kundts Tube/3B2203.md
index ed891dfa..451c198a 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2203 Kundts Tube/3B2203.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2203 Kundts Tube/3B2203.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2203/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2203_figure_0.png
+
.
```
@@ -36,29 +35,27 @@ name: 3b2203/figure_0.png
### Longitudinal Wave Demonstrator.
Ask the students to concentrate on the white ends of the sticks of the wave demonstrator. These white ends represent "air molecules". The distance between the white ends is a measure for “air pressure”.
Apply, by hand, a short pulse into this wave demonstrator and see how a compression displaces itself horizontally, reflects from the free end, and returns. This is similar to a pulse on a rope which they have seen before, so stress the difference: Now the "particles" have a velocity in the same direction as the pulse travels while on the rope the particle velocity is transverse to the movement of the pulse.
- Also stress the observation that particle velocity differs from the velocity of the pulse. Make, by hand a standing wave in the wave demonstrator, with around 3, 4 nodes in it (see {numref}`Figure {number} <3b2203/figure_1.png>`A). Pay attention to "particles" that are not moving at all and "particles" that are moving fast, and observe that in places without "particle"-movement the distance between the "particles" changes strongly (= strong change in pressure), and in places with strong "particle"-movement the distance between the "particles" is almost constant (= no change in pressure).
+ Also stress the observation that particle velocity differs from the velocity of the pulse. Make, by hand a standing wave in the wave demonstrator, with around 3, 4 nodes in it (see {numref}`Figure {number} <3b2203_figure_1.png>`A). Pay attention to "particles" that are not moving at all and "particles" that are moving fast, and observe that in places without "particle"-movement the distance between the "particles" changes strongly (= strong change in pressure), and in places with strong "particle"-movement the distance between the "particles" is almost constant (= no change in pressure).
*[In this demonstration we stress these two observations, because in textbooks you often see drawings of standing waves in tubes showing either the displacement of air and/or the pressure in air. To students this can be confusing when they relate these pictures to what they see in a demonstration.]*
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2203/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2203_figure_1.png
+
.
```
### Open end tube.
-The camera focuses on the glass tube, the ruler and the frequency-reading of the signal generator (see the position of the camera in Diagram). The signal generator is set to a high amplitude and a loud sound is heard. The frequency is increased until a standing wave is observed in the cork dust (we start around 500 Hz and go up to a couple of kHz). At a standing wave we see that at certain places dust is swept away (anti-nodes in terms of displacement) and at other places dust collects (nodes) (see {numref}`Figure {number} <3b2203/figure_2.png>`). At the open end of the tube cork dust is swept out of the tube. Clearly air is moving fast at that open end (anti-node).
+The camera focuses on the glass tube, the ruler and the frequency-reading of the signal generator (see the position of the camera in Diagram). The signal generator is set to a high amplitude and a loud sound is heard. The frequency is increased until a standing wave is observed in the cork dust (we start around 500 Hz and go up to a couple of kHz). At a standing wave we see that at certain places dust is swept away (anti-nodes in terms of displacement) and at other places dust collects (nodes) (see {numref}`Figure {number} <3b2203_figure_2.png>`). At the open end of the tube cork dust is swept out of the tube. Clearly air is moving fast at that open end (anti-node).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3b2203_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3b2203/figure_2.png
----
.
```
- Closed end tube. The piston is shifted into the tube. The frequency of the signal generator is fixed at $1\mathrm{~kHz}$ (this value enables easy calculations). The piston is displaced until again a standing cork dust pattern appears (see {numref}`Figure {number} <3b2203/figure_1.png>`B). We measure $17 \mathrm{~cm}$ distance between two anti-nodes (half $\lambda$). With $c=\lambda f$ we get $c=340 \mathrm{~m/s}$.
+ Closed end tube. The piston is shifted into the tube. The frequency of the signal generator is fixed at $1\mathrm{~kHz}$ (this value enables easy calculations). The piston is displaced until again a standing cork dust pattern appears (see {numref}`Figure {number} <3b2203_figure_1.png>`B). We measure $17 \mathrm{~cm}$ distance between two anti-nodes (half $\lambda$). With $c=\lambda f$ we get $c=340 \mathrm{~m/s}$.
## Explanation
In Kundt's tube (1866) the cork dust is so light that moving air easily displaces it when a strong standing wave occurs. The cork is swept away at places where the air is in motion. The cork dust collects at places where the air is not moving. Referring to the Longitudinal Wave Demonstrator highlights what happens in Kundt's tube, e.q.:
@@ -67,13 +64,12 @@ name: 3b2203/figure_2.png
- At an open end the displacement of air goes beyond the length of the tube, so for nodes and anti-nodes the tube is a little "longer".
## Remarks
- * In the area where cork dust collects, small vertical “curtains” appear, separated by around 4-5mm (see {numref}`Figure {number} <3b2203/figure_3.png>`). Probably this is caused by higher harmonics? We are not sure and until now found nothing of this phenomenon in literature. When it is a higher harmonics it can be useful to try to perform the experiment with other particles, because then a different curtain-separation will occur? When you know more we like to hear from you.
+ * In the area where cork dust collects, small vertical “curtains” appear, separated by around 4-5mm (see {numref}`Figure {number} <3b2203_figure_3.png>`). Probably this is caused by higher harmonics? We are not sure and until now found nothing of this phenomenon in literature. When it is a higher harmonics it can be useful to try to perform the experiment with other particles, because then a different curtain-separation will occur? When you know more we like to hear from you.
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 3b2203_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 3b2203/figure_3.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2204 Sonometer by Hand/3B2204.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2204 Sonometer by Hand/3B2204.md
index e496cd0e..fe434405 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2204 Sonometer by Hand/3B2204.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2204 Sonometer by Hand/3B2204.md
@@ -21,24 +21,22 @@
## Presentation
One rope is hung across the bar and loaded with $0.5 \mathrm{~kg}$. The demonstrator graps the other end, standing about $8 \mathrm{~m}$ away and swings the rope vertically to a standing wave of one half wavelength. When he doubles his speed one complete wave appears in the rope.
-With his other hand he also takes the second rope that is loaded with $2 \mathrm{~kg}$. First he makes one complete wavelength in the rope that is loaded with $.5 \mathrm{~kg}$. Then he starts moving the second hand in the same rhythm. A half wave will appear in this second rope ({numref}`Figure {number} <3b2204/figure_0.png>`).
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2204/figure_0.png
----
+With his other hand he also takes the second rope that is loaded with $2 \mathrm{~kg}$. First he makes one complete wavelength in the rope that is loaded with $.5 \mathrm{~kg}$. Then he starts moving the second hand in the same rhythm. A half wave will appear in this second rope ({numref}`Figure {number} <3b2204_figure_0.png>`).
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2204_figure_0.png
+
.
```
The demonstrator takes the rope that is four times as heavy and loads it with $2 \mathrm{~kg}$. Slowly moving he makes a standing wave of one half wavelength. Doubling his speed, he makes a standing wave of one complete wavelength.
-With his second hand he takes a single rope, also loaded with $2 \mathrm{~kg}$ and when this rope moves in the same rhythm as his first hand is doing for a complete wavelength, then a half wavelength appears in this second rope ({numref}`Figure {number} <3b2204/figure_1.png>`).
+With his second hand he takes a single rope, also loaded with $2 \mathrm{~kg}$ and when this rope moves in the same rhythm as his first hand is doing for a complete wavelength, then a half wavelength appears in this second rope ({numref}`Figure {number} <3b2204_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2204_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2204/figure_1.png
----
.
```
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/3B2205.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/3B2205.md
index dbb3a81c..bac3b04f 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/3B2205.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/3B2205.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2205/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2205_figure_0.png
+
.
```
@@ -27,19 +26,10 @@ name: 3b2205/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/8tD93kUjvnk?si=mBpgnwuE_BOYxMeq
+```
-Set up the demonstration as shown in Diagram and connect the detector, that is placed near the string, to the interface. The software is set up to have an oscilloscope screen and an FFT display (frequency spectrum) as in {numref}`Figure {number} <3b2205/figure_1.png>`.
+Set up the demonstration as shown in Diagram and connect the detector, that is placed near the string, to the interface. The software is set up to have an oscilloscope screen and an FFT display (frequency spectrum) as in {numref}`Figure {number} <3b2205_figure_1.png>`.
1. Load the string with . $5 \mathrm{~kg}$ (see Diagram, mass hanging at the end of the lever). Pluck, by hand/nail, the string (moving it in a vertical direction). We do this in two ways:
@@ -63,15 +53,14 @@ Set up the demonstration as shown in Diagram and connect the detector, that is p
2a: $140-, 268-, 405-, 541-, 677-, 799-, 939\mathrm{~Hz}$;
- 2b: $140-, 405-, 678\mathrm{~Hz}$ (see {numref}`Figure {number} <3b2205/figure_1.png>`).
+ 2b: $140-, 405-, 678\mathrm{~Hz}$ (see {numref}`Figure {number} <3b2205_figure_1.png>`).
Compare these data with the results of the first part of our demonstration and show that the ratio's $140 / 102 ; 268 / 190 ; 405 / 288 ; 541 / 385$; etc. are all very close to $\sqrt{2}$.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2205/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2205_figure_1.png
+
.
```
## Simulation:
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/qr_images/qrcode_8tD93kUjvnk_si_mBpgnwuE_BOYxMeq_.svg b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/qr_images/qrcode_8tD93kUjvnk_si_mBpgnwuE_BOYxMeq_.svg
new file mode 100644
index 00000000..fe5aefba
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2205 Plucking a String/qr_images/qrcode_8tD93kUjvnk_si_mBpgnwuE_BOYxMeq_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2206 Microwave Oven Standing Waves/3B2206.md b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2206 Microwave Oven Standing Waves/3B2206.md
index 0db49938..83518b30 100644
--- a/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2206 Microwave Oven Standing Waves/3B2206.md
+++ b/book/book/3 oscillations and waves/3B wave/3B22 Standing/3B2206 Microwave Oven Standing Waves/3B2206.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b2206/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b2206_figure_0.png
+
.
```
@@ -31,23 +30,21 @@ name: 3b2206/figure_0.png
## Presentation
-Shortly the operation of the microwave oven is explained to the students. This is done by showing the cavity magnetron to them and explaining its operation (see {numref}`Figure {number} <3b2206/figure_1.png>`). See for instance: https://www.radartutorial.eu/08.transmitters/tx08.en.html
+Shortly the operation of the microwave oven is explained to the students. This is done by showing the cavity magnetron to them and explaining its operation (see {numref}`Figure {number} <3b2206_figure_1.png>`). See for instance: https://www.radartutorial.eu/08.transmitters/tx08.en.html
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b2206_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b2206/figure_1.png
----
.
```
-The oven is switched ON for around 2 minutes. After around 30 seconds it is observed that the marsh-mallows rise. After two minutes it is clearly observed that the rising occurs only at certain spots (see {numref}`Figure {number} <3b2206/figure_2.png>`).
+The oven is switched ON for around 2 minutes. After around 30 seconds it is observed that the marsh-mallows rise. After two minutes it is clearly observed that the rising occurs only at certain spots (see {numref}`Figure {number} <3b2206_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3b2206_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3b2206/figure_2.png
----
.
```
We measure $d =10 \mathrm{~cm}$.
@@ -56,7 +53,7 @@ name: 3b2206/figure_2.png
The rising of the marshmallows at certain spots only, shows that there is heating only at certain spots. This can be explained by assuming a standing em-wave in the cavity that the oven is.
### Discussion:
- Knowing that the magnetron-frequency is $2.45 \mathrm{Ghz}$, makes that the wavelength in air of the em-wave equals $12.2 \mathrm{~cm}$. Then possible standing waves are standing waves with $n(12.2) \mathrm{cm}[n=1,2,3, \ldots]$, and we expect heating at multiples of half wavelength distances, so at $\mathrm{n}(6.1) \mathrm{cm}$. We measure heating hills at $10 \mathrm{~cm}$ separation (see {numref}`Figure {number} <3b2206/figure_2.png>`). This means that the standing wave has a wavelength of $20 \mathrm{~cm}$. This can only mean that the frequency of the em-wave inside the oven is less than $2.45 \mathrm{MHz}$. supposing it is half that frequency, then we expect standing waves with $\mathrm{n}(24.4) \mathrm{cm}$, and heating hills at $12.2 \mathrm{~cm}$ separation. That we measure $10 \mathrm{~cm}$ can be caused by the dielectric constant of marshmallows being $>1$, causing a smaller wavelength inside the marshmallows.
+ Knowing that the magnetron-frequency is $2.45 \mathrm{Ghz}$, makes that the wavelength in air of the em-wave equals $12.2 \mathrm{~cm}$. Then possible standing waves are standing waves with $n(12.2) \mathrm{cm}[n=1,2,3, \ldots]$, and we expect heating at multiples of half wavelength distances, so at $\mathrm{n}(6.1) \mathrm{cm}$. We measure heating hills at $10 \mathrm{~cm}$ separation (see {numref}`Figure {number} <3b2206_figure_2.png>`). This means that the standing wave has a wavelength of $20 \mathrm{~cm}$. This can only mean that the frequency of the em-wave inside the oven is less than $2.45 \mathrm{MHz}$. supposing it is half that frequency, then we expect standing waves with $\mathrm{n}(24.4) \mathrm{cm}$, and heating hills at $12.2 \mathrm{~cm}$ separation. That we measure $10 \mathrm{~cm}$ can be caused by the dielectric constant of marshmallows being $>1$, causing a smaller wavelength inside the marshmallows.
## Sources
* https://www.radartutorial.eu/08.transmitters/tx08.en.html
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/3B4001.md b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/3B4001.md
index bee32069..25888849 100644
--- a/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/3B4001.md
+++ b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/3B4001.md
@@ -9,45 +9,34 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 3b4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 3b4001_figure_0.png
+
.
```
## Equipment
* Two loudspeakers, one standing, the other swinging (see Diagram).
* Two signal generators, with high frequency stability.
- * Two switches (see {numref}`Figure {number} <3b4001/figure_1.png>`).
+ * Two switches (see {numref}`Figure {number} <3b4001_figure_1.png>`).
* Camera.
* Monitor with large screen.
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/WsPxsf9Npsk?si=wW1m5pQPoSp4ho3H
+```
The two speakers are mounted as shown in Diagram. One of the speakers is mounted as a pendulum with an arm of around $1.5 \mathrm{~m}$. In the beginning the pendulum is not moving.
-Both signal generators are set at $1000 \mathrm{~Hz}$ (all four digits are significant!). Switching from one generator to the other (see the switches in {numref}`Figure {number} <3b4001/figure_1.png>`), both amplitudes are set in such a way that both speakers produce the same loudness (switching from one to the other no difference is heard).
+Both signal generators are set at $1000 \mathrm{~Hz}$ (all four digits are significant!). Switching from one generator to the other (see the switches in {numref}`Figure {number} <3b4001_figure_1.png>`), both amplitudes are set in such a way that both speakers produce the same loudness (switching from one to the other no difference is heard).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 3b4001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 3b4001/figure_1.png
----
.
```
@@ -81,13 +70,12 @@ The beat frequency is just the difference in frequency of the two waves: $f_{1}-
### Doppler
-The shift to $f_{R}$ in the observed frequency, of a wave send with a frequency $f_{s}$ as result of relative motion, is $f_{R}=f_{s} \frac{1}{1-\frac{v_{s}}{c} \cos \theta}$ (see {numref}`Figure {number} <3b4001/figure_2.png>`).
+The shift to $f_{R}$ in the observed frequency, of a wave send with a frequency $f_{s}$ as result of relative motion, is $f_{R}=f_{s} \frac{1}{1-\frac{v_{s}}{c} \cos \theta}$ (see {numref}`Figure {number} <3b4001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 3b4001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 3b4001/figure_2.png
----
.
```
With $\theta=O$ (moving towards the audience) this reduces to: $f_{R}=f_{s} \frac{1}{1-\frac{v_{s}}{c}}$, showing an
@@ -109,7 +97,7 @@ When the swinging speaker is set at $995 \mathrm{~Hz}$ the situation is just the
So, observing the beatfrequency we can in this way observe that the frequency increases as the speaker approaches you and lowers when the speaker moves away
## Remarks
- * Contrary to the picture in Diagram we mount the two speakers above each other. The same is done with the two signal generators (see {numref}`Figure {number} <3b4001/figure_1.png>`). So, when the audience sees the two frequency displays of the two generators on the monitor screen, they know which frequency belongs to which speaker.
+ * Contrary to the picture in Diagram we mount the two speakers above each other. The same is done with the two signal generators (see {numref}`Figure {number} <3b4001_figure_1.png>`). So, when the audience sees the two frequency displays of the two generators on the monitor screen, they know which frequency belongs to which speaker.
- Calculating the frequency by means of $f_{R}=f_{s} \frac{1}{1-\frac{v_{s}}{c}}$ or $f_{R}=f_{s} \frac{1}{1+\frac{V_{s}}{c}}$ can be done quicker by means of $f_{R}=f_{s} \frac{1}{1-\frac{v_{s}}{c}}=f_{s} \frac{1}{1+\frac{v_{s}}{c}}$ or
$$
@@ -121,7 +109,6 @@ Extra demo to illustrate the Doppler Effect.
```{iframe} https://www.youtube.com/watch?v=nd9OHoIjmnQ
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_WsPxsf9Npsk_si_wW1m5pQPoSp4ho3H_.svg b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_WsPxsf9Npsk_si_wW1m5pQPoSp4ho3H_.svg
new file mode 100644
index 00000000..50489917
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_WsPxsf9Npsk_si_wW1m5pQPoSp4ho3H_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_watch_v_nd9OHoIjmnQ.svg b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_watch_v_nd9OHoIjmnQ.svg
new file mode 100644
index 00000000..245aac0d
--- /dev/null
+++ b/book/book/3 oscillations and waves/3B wave/3B40 Doppler/3B4001 Doppler/qr_images/qrcode_watch_v_nd9OHoIjmnQ.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1001 Constant Volume Gas Thermometer/4A1001.md b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1001 Constant Volume Gas Thermometer/4A1001.md
index f7c86e7d..206006eb 100644
--- a/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1001 Constant Volume Gas Thermometer/4A1001.md
+++ b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1001 Constant Volume Gas Thermometer/4A1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4a1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4a1001_figure_0.png
+
.
```
@@ -34,16 +33,15 @@ First, the container is dipped into the beaker with ice-water. The pressure redu
Finally, the container is placed in the polystyrene box and then liquid nitrogen is poured into it. While the container cools down the liquid nitrogen boils vigorously, quieting when the boiling point of the liquid nitrogen is reached. Then the pressure is read. The three measured points are fitted in the graph on the overhead sheet and it can be observed that the three measured points show a linear relationship, intersecting the $T$-axis at around $-270^{\circ} \mathrm{C}$.
## Explanation
-The product of pressure and volume of a gas depends strongly on the temperature of that gas. So pressure or volume can be used as a thermometric quantity. In this demonstration pressure is used as such and $\mathrm{V}$ is kept constant (one liter). So we speak of a constant volume gas thermometer. $\mathrm{pV}=\mathrm{nRT}$, making $\mathrm{T}=(\mathrm{V} / \mathrm{RT}) \mathrm{p}$, and so an appropriate temperature scale is defined as $\mathrm{T}=\mathrm{Ap}$. For calibration only one constant is needed now. So when we measure pressure at two temperatures and draw a straight line between them we can read from this graph the temperature corresponding to any other pressure $\left(T_{2} / T_{1}=p_{2} / \mathrm{p}_{1}\right)$. Extrapolating this graph, we see that there is a hypothetical temperature $\left(-273,15^{\circ} \mathrm{C}\right)$ at which the pressure would become zero. This extrapolated zero-pressure temperature is used as the basis for a temperature scale: $\mathrm{p}$ is directly proportional to this Kelvin temperature (see {numref}`Figure {number} <4a1001/figure_1.png>`)
+The product of pressure and volume of a gas depends strongly on the temperature of that gas. So pressure or volume can be used as a thermometric quantity. In this demonstration pressure is used as such and $\mathrm{V}$ is kept constant (one liter). So we speak of a constant volume gas thermometer. $\mathrm{pV}=\mathrm{nRT}$, making $\mathrm{T}=(\mathrm{V} / \mathrm{RT}) \mathrm{p}$, and so an appropriate temperature scale is defined as $\mathrm{T}=\mathrm{Ap}$. For calibration only one constant is needed now. So when we measure pressure at two temperatures and draw a straight line between them we can read from this graph the temperature corresponding to any other pressure $\left(T_{2} / T_{1}=p_{2} / \mathrm{p}_{1}\right)$. Extrapolating this graph, we see that there is a hypothetical temperature $\left(-273,15^{\circ} \mathrm{C}\right)$ at which the pressure would become zero. This extrapolated zero-pressure temperature is used as the basis for a temperature scale: $\mathrm{p}$ is directly proportional to this Kelvin temperature (see {numref}`Figure {number} <4a1001_figure_1.png>`)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4a1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4a1001/figure_1.png
----
.
```
-To complete the definition of $T$ one point of the graph is specified. For this the triple point of water is chosen. This occurs at $0.01^{\circ} \mathrm{C}$ and this point is defined as having the value $273.16\mathrm{~K}$ (see {numref}`Figure {number} <4a1001/figure_1.png>`).
+To complete the definition of $T$ one point of the graph is specified. For this the triple point of water is chosen. This occurs at $0.01^{\circ} \mathrm{C}$ and this point is defined as having the value $273.16\mathrm{~K}$ (see {numref}`Figure {number} <4a1001_figure_1.png>`).
## Remarks
- Instead of the beaker with ice-water we sometimes use the room temperature as a point of measurement. Then we start the measurement with this point and so we save time in doing the demonstration.
diff --git a/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/4A1002.md b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/4A1002.md
index 003724c9..039c7be9 100644
--- a/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/4A1002.md
+++ b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/4A1002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4a1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4a1002_figure_0.png
+
.
```
@@ -40,7 +39,6 @@ name: 4a1002/figure_0.png
```{iframe} https://www.youtube.com/watch?v=suJrnW3AP90&t=14s
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/qr_images/qrcode_watch_v_suJrnW3AP90_t_14s.svg b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/qr_images/qrcode_watch_v_suJrnW3AP90_t_14s.svg
new file mode 100644
index 00000000..f2db9827
--- /dev/null
+++ b/book/book/4 thermodynamics/4A thermal properties of matter/4A10 Thermometry/4A1002 Inverted Thermometer/qr_images/qrcode_watch_v_suJrnW3AP90_t_14s.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/4B1001.md b/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/4B1001.md
index ca92a8a9..24b62bf5 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/4B1001.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/4B1001.md
@@ -1,25 +1,15 @@
# 01 Joule's Experiment
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/kfT8paSgfO4?si=96wjx7SVOD-SwyfM
+```
## Aim
To show the conversion of mechanical energy into heat (and its proportionality with temperature).
```{figure} figures/figure_3.jpg
----
-width: 70%
-name: 4b1001/figure_3
----
+:width: 70%
+:label: 4b1001_figure_3
+
.
```
@@ -28,11 +18,10 @@ name: 4b1001/figure_3
* 4B60 (Mechanical Equivalent of Heat)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b1001_figure_0.png
+
.
```
@@ -47,10 +36,9 @@ name: 4b1001/figure_0.png
* Two cursors on each ruler.
```{figure} figures/figure_4.jpg
----
-width: 70%
-name: 4b1001/figure_4
----
+:width: 70%
+:label: 4b1001_figure_4
+
.
```
@@ -61,12 +49,11 @@ Set up the equipment as shown in Diagram. Explain the set-up to the students and
3. Lift the mass to a height of $1.5 \mathrm{~m}$ above the ground and let it go. The measured temperature-rise will be double the value we measured in the first . $75 \mathrm{~m}$-experiment. We conclude a linear relationship between mechanical work and temperature rise (or heat).
## Explanation
-Mechanical work is transformed into heat in the system (See {numref}`Figure {number} <4b1001/figure_1.png>` 1). Part of that heat is dissipated in the resistor.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b1001/figure_1.png
----
+Mechanical work is transformed into heat in the system (See {numref}`Figure {number} <4b1001_figure_1.png>` 1). Part of that heat is dissipated in the resistor.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b1001_figure_1.png
+
.
```
@@ -75,13 +62,12 @@ Doubling the mechanical energy shows that the temperature rise is doubling. So t
## Remarks
- The mass that drives the system has to go down relatively slow, otherwise the kinetic energy of this mass is too large compared to the energy that enters the system.
- The temperature rise of the system is measured in the resistor (part of the total system). Of course there are losses in all transformations involved. We suppose that the efficiencies are constant for different values of $h$, then $\Delta T \propto \Delta U$.
-- When recording the thermocouple $\mathrm{mV}$-reading we find a figure as shown in {numref}`Figure {number} <4b1001/figure_2.png>`
+- When recording the thermocouple $\mathrm{mV}$-reading we find a figure as shown in {numref}`Figure {number} <4b1001_figure_2.png>`
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4b1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4b1001/figure_2.png
----
.
```
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/qr_images/qrcode_kfT8paSgfO4_si_96wjx7SVOD_SwyfM_.svg b/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/qr_images/qrcode_kfT8paSgfO4_si_96wjx7SVOD_SwyfM_.svg
new file mode 100644
index 00000000..a8dd240b
--- /dev/null
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B10 Heat Capacity and Specific Heat/4B1001 Joules Experiment/qr_images/qrcode_kfT8paSgfO4_si_96wjx7SVOD_SwyfM_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B20 Convection/4B2001 Cooling by Insulation/4B2001.md b/book/book/4 thermodynamics/4B heat and the first law/4B20 Convection/4B2001 Cooling by Insulation/4B2001.md
index f0d30171..b2ddfc7c 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B20 Convection/4B2001 Cooling by Insulation/4B2001.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B20 Convection/4B2001 Cooling by Insulation/4B2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b2001_figure_0.png
+
.
```
@@ -31,17 +30,16 @@ The presentation is set up as shown in the diagram. The circuit is a Wheatstone
The current is increased to $25\mathrm{~A}$. The oscilloscope shows that the Wheatstone bridge becomes unbalanced: the line on the screen displaces itself slowly from its zero reference line (stable after about half a minute). This unbalance must be due to the temperature-difference between the insulated - and bare copper wire. Students are asked which of the two wires will have the highest temperature. (Our experience is that almost all the students intuitively guess that the insulated wire has the highest temperature.) Now the bridge is balanced by means of the rheostat. The new balance of the bridge shows clearly that the bare copper wire has increased most its resistance value, so this wire has a higher temperature than the insulated wire!
## Explanation
-See {numref}`Figure {number} <4b2001/figure_1.png>`A. $T_{1}$ is the temperature of the hotter surface and $T_{o}$ the temperature of the colder surroundings.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b2001/figure_1.png
----
+See {numref}`Figure {number} <4b2001_figure_1.png>`A. $T_{1}$ is the temperature of the hotter surface and $T_{o}$ the temperature of the colder surroundings.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b2001_figure_1.png
+
.
```
The rate of flow of heat $(\Phi)$ transferred through a surface $(A)$ from $T_{1}$ to the surroundings with temperature $T_{o}$ is given by $\Phi=\alpha A\left(T_{1}-T_{0}\right)$ ( $\alpha$ is the heat transfer coefficient accounting for convective and radiative heat transfer to the surroundings). This can also be written as $T_{1}-T_{0}=\Phi \frac{1}{\alpha A} \cdot \Phi=\alpha A\left(T_{1}-T_{0}\right)$ is determined by the electric power dissipated in the wire. $\frac{1}{\alpha A}=R_{t h}$ is the so called thermal resistance. The higher $R_{t h}$, the higher the temperature of the wire ( $T_{1}$ ) will be. In the situation of the bare copper wire $R_{t h}=\frac{1}{\alpha 2 \pi r_{1} L}$ ( $L$ being the length of the wire).
-In the situation of the insulated copper wire (see {numref}`Figure {number} <4b2001/figure_1.png>`B) $R_{t h}$ is made up of two thermal resistances in series: one resistance opposing the conduction through the insulation ( $R_{t h 1}$ ) and the second opposing the transfer from the outer surface to the surrounding air ( $R_{\text {th2 }}$ ). The problem of conduction through a cilindrical wall is treated in many textbooks:
+In the situation of the insulated copper wire (see {numref}`Figure {number} <4b2001_figure_1.png>`B) $R_{t h}$ is made up of two thermal resistances in series: one resistance opposing the conduction through the insulation ( $R_{t h 1}$ ) and the second opposing the transfer from the outer surface to the surrounding air ( $R_{\text {th2 }}$ ). The problem of conduction through a cilindrical wall is treated in many textbooks:
$R_{t h 1}=\frac{1}{2 \pi L \lambda} \ln \frac{r_{2}}{r_{1}}$. The total thermal resistance of the insulated copper wire is then $\left(\frac{1}{2 \pi L \lambda} \ln \frac{r_{2}}{r_{1}}\right)+\left(\frac{1}{\alpha 2 \pi r_{2} L}\right)$.
@@ -54,13 +52,12 @@ So we compare $R_{t h}$ with $R_{t h 1}+R_{t h 2}$;so we compare $R_{t h}=\frac{
* Do not exceed the current above $25\mathrm{~A}$ because of excessive heating of wires.
* We use an oscilloscope as a balance-detector because then the increasing unbalance during heating up is clearly visible by a large group.
* As rheostat we use a large slide resistance. With this slide resistance it is clearly visible in which direction the Wheatstone bridge is unbalanced when the copper wire heats up.
- * The circuit has a lot of noise induced into it, originating form the magnetic flux captured by the unavoidable large area of the wire loops in the circuit. This broadens the line on the screen of the oscilloscope. That's why we use a low-pass LC filter at the input of the oscilloscope (see {numref}`Figure {number} <4b2001/figure_2.png>`).
+ * The circuit has a lot of noise induced into it, originating form the magnetic flux captured by the unavoidable large area of the wire loops in the circuit. This broadens the line on the screen of the oscilloscope. That's why we use a low-pass LC filter at the input of the oscilloscope (see {numref}`Figure {number} <4b2001_figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4b2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4b2001_figure_2.png
+
.
```
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B30 Conduction/4B3001 Cooling by Insulation/4B3001.md b/book/book/4 thermodynamics/4B heat and the first law/4B30 Conduction/4B3001 Cooling by Insulation/4B3001.md
index 56636204..96a5554a 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B30 Conduction/4B3001 Cooling by Insulation/4B3001.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B30 Conduction/4B3001 Cooling by Insulation/4B3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b3001_figure_0.png
+
.
```
@@ -31,17 +30,16 @@ The presentation is set up as shown in the diagram. The circuit is a Wheatstone
The current is increased to $25\mathrm{~A}$. The oscilloscope shows that the Wheatstone bridge becomes unbalanced: the line on the screen displaces itself slowly from its zero reference line (stable after about half a minute). This unbalance must be due to the temperature-difference between the insulated - and bare copper wire. Students are asked which of the two wires will have the highest temperature. (Our experience is that almost all the students intuitively guess that the insulated wire has the highest temperature.) Now the bridge is balanced by means of the rheostat. The new balance of the bridge shows clearly that the bare copper wire has increased most its resistance value, so this wire has a higher temperature than the insulated wire!
## Explanation
-See {numref}`Figure {number} <4b3001/figure_1.png>`A. $T_{1}$ is the temperature of the hotter surface and $T_{o}$ the temperature of the colder surroundings.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b3001/figure_1.png
----
+See {numref}`Figure {number} <4b3001_figure_1.png>`A. $T_{1}$ is the temperature of the hotter surface and $T_{o}$ the temperature of the colder surroundings.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b3001_figure_1.png
+
.
```
The rate of flow of heat $(\Phi)$ transferred through a surface $(A)$ from $T_{1}$ to the surroundings with temperature $T_{o}$ is given by $\Phi=\alpha A\left(T_{1}-T_{0}\right)$ ( $\alpha$ is the heat transfer coefficient accounting for convective and radiative heat transfer to the surroundings). This can also be written as $T_{1}-T_{0}=\Phi \frac{1}{\alpha A} \cdot \Phi=\alpha A\left(T_{1}-T_{0}\right)$ is determined by the electric power dissipated in the wire. $\frac{1}{\alpha A}=R_{t h}$ is the so called thermal resistance. The higher $R_{t h}$, the higher the temperature of the wire ( $T_{1}$ ) will be. In the situation of the bare copper wire $R_{t h}=\frac{1}{\alpha 2 \pi r_{1} L}$ ( $L$ being the length of the wire).
-In the situation of the insulated copper wire (see {numref}`Figure {number} <4b3001/figure_1.png>`B) $R_{t h}$ is made up of two thermal resistances in series: one resistance opposing the conduction through the insulation ( $R_{t h 1}$ ) and the second opposing the transfer from the outer surface to the surrounding air ( $R_{\text {th2 }}$ ). The problem of conduction through a cilindrical wall is treated in many textbooks:
+In the situation of the insulated copper wire (see {numref}`Figure {number} <4b3001_figure_1.png>`B) $R_{t h}$ is made up of two thermal resistances in series: one resistance opposing the conduction through the insulation ( $R_{t h 1}$ ) and the second opposing the transfer from the outer surface to the surrounding air ( $R_{\text {th2 }}$ ). The problem of conduction through a cilindrical wall is treated in many textbooks:
$R_{t h 1}=\frac{1}{2 \pi L \lambda} \ln \frac{r_{2}}{r_{1}}$. The total thermal resistance of the insulated copper wire is then $\left(\frac{1}{2 \pi L \lambda} \ln \frac{r_{2}}{r_{1}}\right)+\left(\frac{1}{\alpha 2 \pi r_{2} L}\right)$.
@@ -54,13 +52,12 @@ So we compare $R_{t h}$ with $R_{t h 1}+R_{t h 2}$;so we compare $R_{t h}=\frac{
* Do not exceed the current above $25\mathrm{~A}$ because of excessive heating of wires.
* We use an oscilloscope as a balance-detector because then the increasing unbalance during heating up is clearly visible by a large group.
* As rheostat we use a large slide resistance. With this slide resistance it is clearly visible in which direction the Wheatstone bridge is unbalanced when the copper wire heats up.
- * The circuit has a lot of noise induced into it, originating form the magnetic flux captured by the unavoidable large area of the wire loops in the circuit. This broadens the line on the screen of the oscilloscope. That's why we use a low-pass LC filter at the input of the oscilloscope (see {numref}`Figure {number} <4b3001/figure_2.png>`).
+ * The circuit has a lot of noise induced into it, originating form the magnetic flux captured by the unavoidable large area of the wire loops in the circuit. This broadens the line on the screen of the oscilloscope. That's why we use a low-pass LC filter at the input of the oscilloscope (see {numref}`Figure {number} <4b3001_figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4b3001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4b3001_figure_2.png
+
.
```
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B40 Radiation/4B4002 StefanBoltzmann Law for Radiation/4B4002.md b/book/book/4 thermodynamics/4B heat and the first law/4B40 Radiation/4B4002 StefanBoltzmann Law for Radiation/4B4002.md
index 7fc7f595..58f2d4cb 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B40 Radiation/4B4002 StefanBoltzmann Law for Radiation/4B4002.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B40 Radiation/4B4002 StefanBoltzmann Law for Radiation/4B4002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b4002_figure_0.png
+
.
```
@@ -37,20 +36,19 @@ The temperature sensor is pressed to the hot plate using the spring/clamp mechan
The electric hot plate is switched on, ***on its lowest setting***. The digital temperature meter shows the rising temperature of the plate.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b4002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b4002_figure_1.png
+
.
```
-As soon as the temperature of the plate reads about $30^{\circ} \mathrm{C}$, the data-acquisition system is started to record temperature- and radiation measurements. Slowly temperature rises and the teacher can go on with his lecture. It takes about 30 minutes to reach a temperature of $150^{\circ} \mathrm{C}$. So, near the end of the lecture the data-acquisition is stopped and the heating of the plate switched off. Studying the four graphs it is clear that the $T^{4}$-graph is the straightest line among the four (see {numref}`Figure {number} <4b4002/figure_1.png>`), so this is the best $P-T$ relationship. ( $T^{3}$-graph "curves" upwards and $T^{5}$-graph "curves" downwards.)
+As soon as the temperature of the plate reads about $30^{\circ} \mathrm{C}$, the data-acquisition system is started to record temperature- and radiation measurements. Slowly temperature rises and the teacher can go on with his lecture. It takes about 30 minutes to reach a temperature of $150^{\circ} \mathrm{C}$. So, near the end of the lecture the data-acquisition is stopped and the heating of the plate switched off. Studying the four graphs it is clear that the $T^{4}$-graph is the straightest line among the four (see {numref}`Figure {number} <4b4002_figure_1.png>`), so this is the best $P-T$ relationship. ( $T^{3}$-graph "curves" upwards and $T^{5}$-graph "curves" downwards.)
## Explanation
We can obtain the Stefan-Boltzmann radiation law by integrating Planck's radiation law over all $\lambda$.
## Remarks
-- Do not start measurements directly after switching on the hot plate. Heat capacity of the system makes that at the very beginning, temperatures in the system are not equally distributed. That's why we start measurements from $30^{\circ} \mathrm{C}$ on. (In {numref}`Figure {number} <4b4002/figure_1.png>` you can see this "switching-on"-effect in the graph at the left-side of the vertical Voltage-axis.)
+- Do not start measurements directly after switching on the hot plate. Heat capacity of the system makes that at the very beginning, temperatures in the system are not equally distributed. That's why we start measurements from $30^{\circ} \mathrm{C}$ on. (In {numref}`Figure {number} <4b4002_figure_1.png>` you can see this "switching-on"-effect in the graph at the left-side of the vertical Voltage-axis.)
This is also the reason why the plate should heat up slowly, otherwise measured temperature and measured radiation are not related properly.
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/4B6002.md b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/4B6002.md
index b8e0d12e..d453d7e0 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/4B6002.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/4B6002.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b6002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b6002_figure_0.png
+
.
```
@@ -26,15 +25,14 @@ name: 4b6002/figure_0.png
## Presentation
-The two $1 \mathrm{~kg}$, chrome steel spheres are smashed together, while the sheet of paper is between them. At the point of contact a hole is burned in the piece of paper (see the enlarged {numref}`Figure {number} <4b6002/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b6002/figure_1.png
----
+The two $1 \mathrm{~kg}$, chrome steel spheres are smashed together, while the sheet of paper is between them. At the point of contact a hole is burned in the piece of paper (see the enlarged {numref}`Figure {number} <4b6002_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b6002_figure_1.png
+
.
```
-The demonstrator will smell the odour of burnt paper. Also a charred hole appears (see the brown rim in {numref}`Figure {number} <4b6002/figure_1.png>`). To convince the audience, this hole is shown to them using a document camera (is present in our lecture rooms).
+The demonstrator will smell the odour of burnt paper. Also a charred hole appears (see the brown rim in {numref}`Figure {number} <4b6002_figure_1.png>`). To convince the audience, this hole is shown to them using a document camera (is present in our lecture rooms).
## Explanation
This demonstration just illustrates the conversion of mechanical energy into heat energy.
@@ -58,7 +56,6 @@ This calculation is just an estimate. Supposing the area a little larger, for in
```{iframe} https://www.youtube.com/watch?v=iW_9_RicnXY
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/qr_images/qrcode_watch_v_iW_9_RicnXY.svg b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/qr_images/qrcode_watch_v_iW_9_RicnXY.svg
new file mode 100644
index 00000000..773a77bf
--- /dev/null
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6002 Smashing/qr_images/qrcode_watch_v_iW_9_RicnXY.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6003 Dropping Lead Shot/4B6003 Dropping Lead Shot.md b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6003 Dropping Lead Shot/4B6003 Dropping Lead Shot.md
index fe9e66d6..ef154913 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6003 Dropping Lead Shot/4B6003 Dropping Lead Shot.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B60 Mechanical Equivalent of Heat/4B6003 Dropping Lead Shot/4B6003 Dropping Lead Shot.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_4B60.03a.jpg
----
-width: 70%
-name: 4b6003/figure_4B6003a.jpg
----
+```{figure} figures/figure_4B60.03a.jpg
+:width: 70%
+:label: 4b6003_figure_4B6003a.jpg
+
.
```
@@ -25,22 +24,20 @@ name: 4b6003/figure_4B6003a.jpg
## Presentation
-The tube is rotated several times over 180 degrees, such that the lead shot drops from one end of the tube to the other end (see the enlarged {numref}`Figure {number} <4b6003/figure_4B60.03b.jpg>`).
-```{figure} figures/figure_4B60.03b.jpg
----
-width: 70%
-name: 4b6003/figure_4B60.03b.jpg
----
+The tube is rotated several times over 180 degrees, such that the lead shot drops from one end of the tube to the other end (see the enlarged {numref}`Figure {number} <4b6003_figure_4B60.03b.jpg>`).
+```{figure} figures/figure_4B60.03b.jpg
+:width: 70%
+:label: 4b6003_figure_4B60.03b.jpg
+
.
```
-```{figure} figures/figure_4B60.03c.jpg
----
-width: 70%
-name: 4b6003/figure_4B60.03c.jpg
----
+```{figure} figures/figure_4B60.03c.jpg
+:width: 70%
+:label: 4b6003_figure_4B60.03c.jpg
+
.
```
-The temperature and the temperature rise is displayed real time (see the inset in the graph in {numref}`Figure {number} <4b6003/figure_4B60.03c.jpg>`).
+The temperature and the temperature rise is displayed real time (see the inset in the graph in {numref}`Figure {number} <4b6003_figure_4B60.03c.jpg>`).
## Explanation
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7001 Clements and Desormes Experiment/4B7001.md b/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7001 Clements and Desormes Experiment/4B7001.md
index e0946503..29e13678 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7001 Clements and Desormes Experiment/4B7001.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7001 Clements and Desormes Experiment/4B7001.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b7001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b7001_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ The valve of the container is closed. By means of the syringe an amount of air i
The ratio of heat capacities, $C_{\rho} / C_{V}$ can now be determined by $\gamma=\frac{C p}{C V}=\frac{h_{1}}{h_{1}-h_{2}}$
## Explanation
-The air in the container and syringe is at room temperature $T_{0}$ and pressure $p_{0}$. Pressing the syringe raises the pressure to $p_{1}$. The manometer reads $h_{1}$. (See {numref}`Figure {number} <4b7001/figure_1.png>`.)
+The air in the container and syringe is at room temperature $T_{0}$ and pressure $p_{0}$. Pressing the syringe raises the pressure to $p_{1}$. The manometer reads $h_{1}$. (See {numref}`Figure {number} <4b7001_figure_1.png>`.)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4b7001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4b7001/figure_1.png
----
.
```
@@ -50,13 +48,13 @@ Adiabatic: $p V^{r}=$ const., $V^{r} d p+p V^{r-1} d V=0,\left(\frac{d p}{d V}\r
These two combined: $\left(\frac{d p}{d V}\right)_{a}=\gamma\left(\frac{d p}{d V}\right)_{i}$
-Consider this for the same $d V$ in both processes (see {numref}`Figure {number} <4b7001/figure_1.png>`) and we find:
+Consider this for the same $d V$ in both processes (see {numref}`Figure {number} <4b7001_figure_1.png>`) and we find:
$\frac{d p_{a}}{d p_{i}}=\gamma=\frac{h_{1}}{h_{1}-h_{2}}$
## Remarks
* It is easy to repeat the experiment a number of times.
- * Instead of starting the experiment by pressing air into the container it can also be performed by sucking air out of it. ({numref}`Figure {number} <4b7001/figure_1.png>` will be different, of course.)
+ * Instead of starting the experiment by pressing air into the container it can also be performed by sucking air out of it. ({numref}`Figure {number} <4b7001_figure_1.png>` will be different, of course.)
## Sources
* Freier, George D. and Anderson, Frances J., A demonstration handbook for physics, pag. H.14
diff --git a/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7002 Fire Pump/4B7002.md b/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7002 Fire Pump/4B7002.md
index 60876fbd..9128c042 100644
--- a/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7002 Fire Pump/4B7002.md
+++ b/book/book/4 thermodynamics/4B heat and the first law/4B70 Adiabatic Processes/4B7002 Fire Pump/4B7002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4b7002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4b7002_figure_0.png
+
.
```
diff --git a/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1001 Compressing a Gas/4C1001.md b/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1001 Compressing a Gas/4C1001.md
index 20fd835b..b32ca753 100644
--- a/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1001 Compressing a Gas/4C1001.md
+++ b/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1001 Compressing a Gas/4C1001.md
@@ -11,11 +11,10 @@
* 4C10 (PVT Surfaces)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c1001_figure_0.png
+
.
```
@@ -31,7 +30,7 @@ name: 4c1001/figure_0.png
## Presentation
- Preparation: Set up the equipment as shown in Diagram. The mass of 5 kg is large compared to the cylinder with piston. We take care that the set up is also stable when that mass is positioned on the platform of the piston shaft. (See the thread that holds and guides the mass when moving, and the slanting shaft that fixes the vertical shaft that holds the cylinder. Also the blocks of wood under the cylinder give extra support.). The pressure sensor is connected to the cylinder. A thin wire, connected to the top of the mass and wound around the pulley of the Rotary Motion Sensor, makes it possible to measure the volume of the cylinder. In the software of Science Workshop a graph is prepared, showing pressure as function of cylinder volume. Pressure can be displayed directly in the graph; displaying volume on the x-axis needs some calculation, using the piston area. (see {numref}`Figure {number} <4c1001/figure_1.png>` 1).
+ Preparation: Set up the equipment as shown in Diagram. The mass of 5 kg is large compared to the cylinder with piston. We take care that the set up is also stable when that mass is positioned on the platform of the piston shaft. (See the thread that holds and guides the mass when moving, and the slanting shaft that fixes the vertical shaft that holds the cylinder. Also the blocks of wood under the cylinder give extra support.). The pressure sensor is connected to the cylinder. A thin wire, connected to the top of the mass and wound around the pulley of the Rotary Motion Sensor, makes it possible to measure the volume of the cylinder. In the software of Science Workshop a graph is prepared, showing pressure as function of cylinder volume. Pressure can be displayed directly in the graph; displaying volume on the x-axis needs some calculation, using the piston area. (see {numref}`Figure {number} <4c1001_figure_1.png>` 1).
## Presentation
### Preparation:
@@ -40,7 +39,7 @@ Set up the equipment as shown in Diagram. The mass of $5 \mathrm{~kg}$ is large
The pressure sensor is connected to the cylinder. A thin wire, connected to the top of the mass and wound around the pulley of the Rotary Motion Sensor, makes it possible to measure the volume of the cylinder.
-In the software of Science Workshop a graph is prepared, showing pressure as function of cylinder volume. Pressure can be displayed directly in the graph; displaying volume on the $x$-axis needs some calculation, using the piston area. (see {numref}`Figure {number} <4c1001/figure_1.png>`).
+In the software of Science Workshop a graph is prepared, showing pressure as function of cylinder volume. Pressure can be displayed directly in the graph; displaying volume on the $x$-axis needs some calculation, using the piston area. (see {numref}`Figure {number} <4c1001_figure_1.png>`).
### Presentation:
@@ -50,29 +49,27 @@ The mass of $5 \mathrm{~kg}$ is placed on the platform. A thumbscrew turned into
Ask the students what they expect to see on the displayed graph.
-Then data-acquisition is started, slowly the thumbscrew is released and the piston slides downward, compressing the gas. When equilibrium is reached the data acquisition is stopped. The gas volume is compressed to around $70 \mathrm{ml}$. On the ruler we can see that the mass has fallen around $3.5 \mathrm{~cm}$. A graph as displayed in {numref}`Figure {number} <4c1001/figure_1.png>` is the result of this demonstration.
+Then data-acquisition is started, slowly the thumbscrew is released and the piston slides downward, compressing the gas. When equilibrium is reached the data acquisition is stopped. The gas volume is compressed to around $70 \mathrm{ml}$. On the ruler we can see that the mass has fallen around $3.5 \mathrm{~cm}$. A graph as displayed in {numref}`Figure {number} <4c1001_figure_1.png>` is the result of this demonstration.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4c1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4c1001/figure_1.png
----
.
```
- At first sight, the graph looks almost like a straight line. Usually students expect a more curved line because that is what is presented to them in textbooks. We perform a power fit on these results, showing that when in such a way our results are extrapolated, the function resembles the pictures we see in textbooks.
-- In the software we calculate the area under the measured PV curve, in order to know the work done on the gas in the cylinder. We find around 4J (see: Area in {numref}`Figure {number} <4c1001/figure_2.png>`). Then we calculate the work done by the mass: $\Delta U=m g \Delta h=5 \times 10 \times 0.035=1.75]$ ! The difference is surprising; are we gaining in energy? Have we found a possible perpetuum mobile? Ask the students how they can explain this.
+- In the software we calculate the area under the measured PV curve, in order to know the work done on the gas in the cylinder. We find around 4J (see: Area in {numref}`Figure {number} <4c1001_figure_2.png>`). Then we calculate the work done by the mass: $\Delta U=m g \Delta h=5 \times 10 \times 0.035=1.75]$ ! The difference is surprising; are we gaining in energy? Have we found a possible perpetuum mobile? Ask the students how they can explain this.
## Explanation
-What the software is calculating is the work done on the gas inside the cylinder. From outside not only the mass of $5 \mathrm{~kg}$ is standing on the piston, also the outside air with a pressure of $100 \mathrm{kPa}$ is "standing" on it. This is an isobaric part of the area under the graph, representing an amount of work of around $100 \mathrm{kPa} \times 30 \mathrm{ml}=3 \mathrm{~J}$ (see {numref}`Figure {number} <4c1001/figure_2.png>`). The remaining $1 \mathrm{~J}$ is delivered by the mass of $5 \mathrm{~kg}$. (The remaining $0.75 \mathrm{~J}$, to get $1.75 \mathrm{~J}$, is lost elsewhere.)
+What the software is calculating is the work done on the gas inside the cylinder. From outside not only the mass of $5 \mathrm{~kg}$ is standing on the piston, also the outside air with a pressure of $100 \mathrm{kPa}$ is "standing" on it. This is an isobaric part of the area under the graph, representing an amount of work of around $100 \mathrm{kPa} \times 30 \mathrm{ml}=3 \mathrm{~J}$ (see {numref}`Figure {number} <4c1001_figure_2.png>`). The remaining $1 \mathrm{~J}$ is delivered by the mass of $5 \mathrm{~kg}$. (The remaining $0.75 \mathrm{~J}$, to get $1.75 \mathrm{~J}$, is lost elsewhere.)
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4c1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4c1001/figure_2.png
----
.
```
diff --git a/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1002 Work PdV/4C1002.md b/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1002 Work PdV/4C1002.md
index b26318e8..c7e09850 100644
--- a/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1002 Work PdV/4C1002.md
+++ b/book/book/4 thermodynamics/4C change of state/4C10 pVT Surfaces/4C1002 Work PdV/4C1002.md
@@ -7,11 +7,10 @@
* 4C10 (pVT Surfaces)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c1002_figure_0.png
+
.
```
@@ -34,39 +33,36 @@ The set up is explained to the students. The piston is lifted in its upper posit
The $pV$-graph is shown to the students. Ask them where in this graph a point will appear when we start measuring ( $x=83 \mathrm{~m} /\left[\mathrm{cm}^{3}\right]$ and $y=100 \mathrm{kPa}$ ). Ask them also what we will see happening in the graph when we load the platform with $2 \mathrm{~kg}$.
-Then we close the cylinder and load the platform. The $2 \mathrm{~kg}$ mass goes downward (around $2 \mathrm{~cm}$ ): the gas is compressed (smaller volume; higher pressure). The $pV$ graph of the process appears (see {numref}`Figure {number} <4c1002/figure_1.png>`).
+Then we close the cylinder and load the platform. The $2 \mathrm{~kg}$ mass goes downward (around $2 \mathrm{~cm}$ ): the gas is compressed (smaller volume; higher pressure). The $pV$ graph of the process appears (see {numref}`Figure {number} <4c1002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4c1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4c1002/figure_1.png
----
.
```
Then we ask to students how to calculate the work done on the gas in the cylinder. Two possibilities appear:
1. The mass of $2 \mathrm{~kg}$ is lowered $2 \mathrm{~cm}$, so $\Delta E_{p}=m g \Delta h=2 \times 10 \times 2.10^{-2}=0.4 \mathrm{~J}$;
-2. The area under the measured $pV$-graph. The software calculates it and it shows: $2097.3\mathrm{kPa\cdot ml}$ (see {numref}`Figure {number} <4c1002/figure_2.png>`). The peculiar unit is rewritten and the number is rounded to $2.1 \mathrm{~J}$.
+2. The area under the measured $pV$-graph. The software calculates it and it shows: $2097.3\mathrm{kPa\cdot ml}$ (see {numref}`Figure {number} <4c1002_figure_2.png>`). The peculiar unit is rewritten and the number is rounded to $2.1 \mathrm{~J}$.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4c1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4c1002/figure_2.png
----
.
```
Students are confused seeing the difference between these two numbers ($0.4\mathrm{~J}$) and ($2.1\mathrm{~J}$ ). A very useful discussion follows.
## Explanation
-With a load of $2 \mathrm{~kg}$ on the piston having an area of $8.3 \mathrm{~cm}^{2}$, we get a pressure of $\frac{2 \times 10}{8.3 \times 10^{-4}}=0.241 \times 10^{5} \mathrm{~Pa} \frac{2 \times 10}{8.3 \times 10^{-4}}=0.241 \times 10^{5} \mathrm{~Pa}$. So the pressure inside the cylinder rises from $1 \times 10^{5} \mathrm{~Pa}$ to $1.241 \times 10^{5} \mathrm{~Pa}$. J ust calculation, using Boyle's law, $p_{1} V_{1}=p_{2} V_{2}$ gives: $V_{2}=68.5 \mathrm{~cm}^{3}$. This is very close to what the $pV$-graph shows in its measurements of final pressure and final volume (read the values in {numref}`Figure {number} <4c1002/figure_2.png>`; do not look at the final 'horizontal' part of the graph, because that part is caused by leakage).
+With a load of $2 \mathrm{~kg}$ on the piston having an area of $8.3 \mathrm{~cm}^{2}$, we get a pressure of $\frac{2 \times 10}{8.3 \times 10^{-4}}=0.241 \times 10^{5} \mathrm{~Pa} \frac{2 \times 10}{8.3 \times 10^{-4}}=0.241 \times 10^{5} \mathrm{~Pa}$. So the pressure inside the cylinder rises from $1 \times 10^{5} \mathrm{~Pa}$ to $1.241 \times 10^{5} \mathrm{~Pa}$. J ust calculation, using Boyle's law, $p_{1} V_{1}=p_{2} V_{2}$ gives: $V_{2}=68.5 \mathrm{~cm}^{3}$. This is very close to what the $pV$-graph shows in its measurements of final pressure and final volume (read the values in {numref}`Figure {number} <4c1002_figure_2.png>`; do not look at the final 'horizontal' part of the graph, because that part is caused by leakage).
+
+In calculating the work done on the gas in the cylinder it should be realized that also the outside atmosphere works on the piston by its atmospheric pressure. This is shown in {numref}`Figure {number} <4c1002_figure_3.png>`: The atmospheric pressure works with $1.8 \mathrm{~J}$ , the weight by an amount of 0.43 J (calculated by reducing the pV-diagram to a triangle). This $0.43 \mathrm{~J}$ is close to what was calculated by the potential mechanical energy of the work done by the weight.
-In calculating the work done on the gas in the cylinder it should be realized that also the outside atmosphere works on the piston by its atmospheric pressure. This is shown in {numref}`Figure {number} <4c1002/figure_3.png>`: The atmospheric pressure works with $1.8 \mathrm{~J}$ , the weight by an amount of 0.43 J (calculated by reducing the pV-diagram to a triangle). This $0.43 \mathrm{~J}$ is close to what was calculated by the potential mechanical energy of the work done by the weight.
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 4c1002_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 4c1002/figure_3.png
----
.
```
diff --git a/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/4C3001.md b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/4C3001.md
index d55f01f8..d28d36e5 100644
--- a/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/4C3001.md
+++ b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/4C3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c3001_figure_0.png
+
.
```
@@ -30,42 +29,31 @@ name: 4c3001/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/UqNgZtQOqxc?si=BYJG3-xoJcGA5RsS
+```
### Preparation
The vacuum pump is connected to the cylinder. One rim of the cylinder is greased with vacuum grease, and then one of the square transparent end caps is pressed to the cylinder, creating the bottom of the assembly. The upper rim of the cylinder is also greased, after which the small table is placed inside the cylinder.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4c3001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4c3001_figure_1.png
+
.
```
### Preparation
-Using a dripper, a large drop of water is deposited on the tabletop. The second transparent end cap is put on top of the cylinder and pressed down. The assembly is ready now (see {numref}`Figure {number} <4c3001/figure_1.png>`) and the camera is focused on the drop of water.
+Using a dripper, a large drop of water is deposited on the tabletop. The second transparent end cap is put on top of the cylinder and pressed down. The assembly is ready now (see {numref}`Figure {number} <4c3001_figure_1.png>`) and the camera is focused on the drop of water.
The pump is switched on, after which vigorous boiling can be immediately observed.
This stops, and a quiet drop of water is observed.
-Then, after some time, suddenly the drop of water turns opaque (see {numref}`Figure {number} <4c3001/figure_2.png>`)
+Then, after some time, suddenly the drop of water turns opaque (see {numref}`Figure {number} <4c3001_figure_2.png>`)
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4c3001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4c3001/figure_2.png
----
.
```
@@ -83,7 +71,6 @@ To further showcase the boiling of water at reduced pressure.
```{iframe} https://www.youtube.com/watch?v=A5D-ICLmbfA
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_UqNgZtQOqxc_si_BYJG3_xoJcGA5RsS_.svg b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_UqNgZtQOqxc_si_BYJG3_xoJcGA5RsS_.svg
new file mode 100644
index 00000000..d2d65dd7
--- /dev/null
+++ b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_UqNgZtQOqxc_si_BYJG3_xoJcGA5RsS_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_watch_v_A5D_ICLmbfA.svg b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_watch_v_A5D_ICLmbfA.svg
new file mode 100644
index 00000000..5fd9ab61
--- /dev/null
+++ b/book/book/4 thermodynamics/4C change of state/4C30 Phase Changes Liquid Gas/4C3001 Boiling to Freeze/qr_images/qrcode_watch_v_A5D_ICLmbfA.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4C change of state/4C31 Cooling by Evaporation/4C3101 Evaporating Ether/4C3101.md b/book/book/4 thermodynamics/4C change of state/4C31 Cooling by Evaporation/4C3101 Evaporating Ether/4C3101.md
index 0bebc4dd..410611e0 100644
--- a/book/book/4 thermodynamics/4C change of state/4C31 Cooling by Evaporation/4C3101 Evaporating Ether/4C3101.md
+++ b/book/book/4 thermodynamics/4C change of state/4C31 Cooling by Evaporation/4C3101 Evaporating Ether/4C3101.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c3101/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c3101_figure_0.png
+
.
```
diff --git a/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3301 Dippy Bird/4C3301.md b/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3301 Dippy Bird/4C3301.md
index a6b68856..89cf97ab 100644
--- a/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3301 Dippy Bird/4C3301.md
+++ b/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3301 Dippy Bird/4C3301.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c3301/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c3301_figure_0.png
+
.
```
@@ -36,12 +35,11 @@ Set up the dippy bird and the beaker as shown in the Diagram. Fill the beaker wi
To the teacher it is very instructive to have the students explain what is happening. So just put the bird in your lecture room and let the students break their brains.
## Explanation
-{numref}`Figure {number} <4c3301/figure_1.png>` shows the system. The bird is filled with a liquid (dichloromethane) having low latent heat of evaporation. Only this liquid and its vapour are inside the bird.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4c3301/figure_1.png
----
+{numref}`Figure {number} <4c3301_figure_1.png>` shows the system. The bird is filled with a liquid (dichloromethane) having low latent heat of evaporation. Only this liquid and its vapour are inside the bird.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4c3301_figure_1.png
+
.
```
Initially the system is at equilibrium. There are two spaces to consider: the head with $n_{h}$ moles of vapour and the abdomen with $n_{a}$ moles of vapour.
@@ -51,18 +49,17 @@ Evaporation of water on the beak outside the head draws heat from inside it; the
The rising fluid raises the centre of mass above the pivot point, so the bird dips. The amount of fluid is set so that at full dip the lower end of the tube is exposed to the vapour. A bubble of vapour rises in the tube and fluid drains into the abdomen. The rising bubble transfers heat to the head. The centre of mass drops below the pivot point and the bird bobs up, oscillating back to its starting position.
Due to this fast swinging movement, there is good evaporation of the water on the beak, and the whole cycle described above repeats itself.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4c3301/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4c3301_figure_2.png
+
.
```
-{numref}`Figure {number} <4c3301/figure_2.png>` shows the behaviour of the dippy bird as a heat-engine. Heat flows into the bird at the abdomen and is discarded at the head/beak-side.
+{numref}`Figure {number} <4c3301_figure_2.png>` shows the behaviour of the dippy bird as a heat-engine. Heat flows into the bird at the abdomen and is discarded at the head/beak-side.
### A second bird
-Considering the dippy bird as a heat-engine (see {numref}`Figure {number} <4c3301/figure_2.png>`) induces the idea that it will work as well when, instead of cooling the head, you heat up the abdomen. We tried this by shining light on the dippy's bottom and indeed, the bird dipped! Demonstrating also this version of the dippy bird will once more make clear that the factor that makes heat-engines work is the temperature gradient.
+Considering the dippy bird as a heat-engine (see {numref}`Figure {number} <4c3301_figure_2.png>`) induces the idea that it will work as well when, instead of cooling the head, you heat up the abdomen. We tried this by shining light on the dippy's bottom and indeed, the bird dipped! Demonstrating also this version of the dippy bird will once more make clear that the factor that makes heat-engines work is the temperature gradient.
## Remarks
* We use distilled water instead of tap water, because in our city tap water is hard water and in due time the lime would thermally isolate the beak of the bird.
diff --git a/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3302 Boiling Water at Reduced Pressure/4C3302.md b/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3302 Boiling Water at Reduced Pressure/4C3302.md
index e551270c..8d289af9 100644
--- a/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3302 Boiling Water at Reduced Pressure/4C3302.md
+++ b/book/book/4 thermodynamics/4C change of state/4C33 Vapor Pressure/4C3302 Boiling Water at Reduced Pressure/4C3302.md
@@ -8,11 +8,10 @@
* 4C33 (Vapor Pressure)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4c3302/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4c3302_figure_0.png
+
.
```
@@ -36,11 +35,10 @@ name: 4c3302/figure_0.png
## Presentation
The 2 I flask is half filled with water. Open the cock. The water is made boiling by means of a gas flame.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4c3302/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4c3302_figure_1.png
+
.
```
Make it boil rigorously for about one minute to drive out air. Remove the flame and when you see that vapour no longer blows out of the cock, quickly close it. Then invert the flask (see photo in Diagram).
diff --git a/book/book/4 thermodynamics/4D kinetic theory/4D10 Brownian Motion/4D1001 Brownian Motion/4D1001.md b/book/book/4 thermodynamics/4D kinetic theory/4D10 Brownian Motion/4D1001 Brownian Motion/4D1001.md
index 85bb5da0..5717eb49 100644
--- a/book/book/4 thermodynamics/4D kinetic theory/4D10 Brownian Motion/4D1001 Brownian Motion/4D1001.md
+++ b/book/book/4 thermodynamics/4D kinetic theory/4D10 Brownian Motion/4D1001 Brownian Motion/4D1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4d1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4d1001_figure_0.png
+
.
```
@@ -26,12 +25,11 @@ name: 4d1001/figure_0.png
- Video projector.
## Presentation
-To show Brownian motion we use a solution of polystyrene latex particles in distilled water (see Equipment). A small drop of this solution is placed in the "well" on the microscope slide. The "well" is covered by the thin cover glass (see {numref}`Figure {number} <4d1001/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4d1001/figure_1.png
----
+To show Brownian motion we use a solution of polystyrene latex particles in distilled water (see Equipment). A small drop of this solution is placed in the "well" on the microscope slide. The "well" is covered by the thin cover glass (see {numref}`Figure {number} <4d1001_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4d1001_figure_1.png
+
.
```
@@ -45,7 +43,7 @@ The random zigzag movement can be explained as being the result of the bombardme
## Remarks
- * The drop in the "well" should not touch the walls of the well, because otherwise leakage of liquid is inevitable and this will show as a strong flow in your liquid. So really get a drop something like in {numref}`Figure {number} <4d1001/figure_1.png>`.
+ * The drop in the "well" should not touch the walls of the well, because otherwise leakage of liquid is inevitable and this will show as a strong flow in your liquid. So really get a drop something like in {numref}`Figure {number} <4d1001_figure_1.png>`.
* We get the best image when we focus not on the surface of the liquid but at a certain depth.
diff --git a/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3001 Radiometer of Crooks/4D3001.md b/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3001 Radiometer of Crooks/4D3001.md
index 8f7c4c47..fb0a3a9d 100644
--- a/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3001 Radiometer of Crooks/4D3001.md
+++ b/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3001 Radiometer of Crooks/4D3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4d3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4d3001_figure_0.png
+
.
```
diff --git a/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3002 Rain of Balls/4D3002.md b/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3002 Rain of Balls/4D3002.md
index 9655d82c..0804eddf 100644
--- a/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3002 Rain of Balls/4D3002.md
+++ b/book/book/4 thermodynamics/4D kinetic theory/4D30 Kinetic Motion/4D3002 Rain of Balls/4D3002.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4d3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4d3002_figure_0.png
+
.
```
@@ -40,13 +39,12 @@ First drop, by hand, one ball on the platform and monitor the force-time graph.
- The force diagram shows a strong oscillation of the platform. Using the zoom function of the software, it can be shown that at the beginning there is a strong positive impulse: $F$ - $\Delta t$-area. (The subsequent oscillation averages to zero.)
-Reset the software to a recording mode and then pull the pin out of the end of the pipe: A train of balls falls onto the platform. All students' attention might be attracted to the falling balls, so draw their attention also to the ongoing registration of the graph and digital meter. After the rain of balls is over, the results can be discussed. Especially worthwhile are the high force readings of the individual balls (up to $14 \mathrm{~N}$! See {numref}`Figure {number} <4d3002/figure_1.png>`) in contrast to the low average force on the digital scale $(0.08 \mathrm{~N})$.
+Reset the software to a recording mode and then pull the pin out of the end of the pipe: A train of balls falls onto the platform. All students' attention might be attracted to the falling balls, so draw their attention also to the ongoing registration of the graph and digital meter. After the rain of balls is over, the results can be discussed. Especially worthwhile are the high force readings of the individual balls (up to $14 \mathrm{~N}$! See {numref}`Figure {number} <4d3002_figure_1.png>`) in contrast to the low average force on the digital scale $(0.08 \mathrm{~N})$.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4d3002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4d3002/figure_1.png
----
.
```
@@ -55,13 +53,12 @@ The force exerted by an individual ping-pong ball equals $\vec{F}=\frac{\Delta \
### Force due to one collision
-When we examine the force-time graph it can be seen that the rise time of $\mathrm{F}$ during the collision is in the order of $1 \mathrm{msec}$ (see the registration in {numref}`Figure {number} <4d3002/figure_2.png>`).
+When we examine the force-time graph it can be seen that the rise time of $\mathrm{F}$ during the collision is in the order of $1 \mathrm{msec}$ (see the registration in {numref}`Figure {number} <4d3002_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4d3002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4d3002/figure_2.png
----
.
```
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1001 Falling Down or Falling Up/4F1001.md b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1001 Falling Down or Falling Up/4F1001.md
index 8e66945c..c6533aac 100644
--- a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1001 Falling Down or Falling Up/4F1001.md
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1001 Falling Down or Falling Up/4F1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4f1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4f1001_figure_0.png
+
.
```
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1002 Irreversible Process/4F1002.md b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1002 Irreversible Process/4F1002.md
index 36a1c933..57b0b8f7 100644
--- a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1002 Irreversible Process/4F1002.md
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1002 Irreversible Process/4F1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4f1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4f1002_figure_0.png
+
.
```
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/4F1003.md b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/4F1003.md
index 1fd977a8..63cbe543 100644
--- a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/4F1003.md
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/4F1003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4f1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4f1003_figure_0.png
+
.
```
@@ -27,29 +26,19 @@ name: 4f1003/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/sqekFe3OHYo?si=qUbX-nqCOMq4QCBF
+```
+
+As an introduction a Petri dish is placed on the overhead projector. The dish contains a layer of (transparent) oil. By means of the syringe a large drop of dark ink is spouted into the oil (see {numref}`Figure {number} <4f1003_figure_1.png>` a). Using a flat spatula one rotation is made in the fluid. The drop of dark ink breaks into smaller drops ({numref}`Figure {number} <4f1003_figure_1.png>`b).
-As an introduction a Petri dish is placed on the overhead projector. The dish contains a layer of (transparent) oil. By means of the syringe a large drop of dark ink is spouted into the oil (see {numref}`Figure {number} <4f1003/figure_1.png>` a). Using a flat spatula one rotation is made in the fluid. The drop of dark ink breaks into smaller drops ({numref}`Figure {number} <4f1003/figure_1.png>`b).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4f1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4f1003/figure_1.png
----
.
```
-Now it is suggested to the students to turn the spatula in the liquid into the opposite direction, in order to repair the original drop of ink. This action is performed, but the result is that still more destruction is done to the inkdrops ({numref}`Figure {number} <4f1003/figure_1.png>`c).
+Now it is suggested to the students to turn the spatula in the liquid into the opposite direction, in order to repair the original drop of ink. This action is performed, but the result is that still more destruction is done to the inkdrops ({numref}`Figure {number} <4f1003_figure_1.png>`c).
Next the experiment with the plastic cylinder (see Diagram) is done:
@@ -58,13 +47,12 @@ The space between the two concentric cylinders is filled with glycerine and a co
The experiment can be repeated, even making more turns: the column reforms when the same number of reverse turns is made.
## Explanation
-There is no violation of the entropy law at work in this demonstration. The spreading out of the ink does not represent any increase in entropy or disorder. An enlarged top view of the space between the two cylinders (see {numref}`Figure {number} <4f1003/figure_2.png>`) shows that molecules on the inner edge of the liquid rotate through angles different from those in the middle or outer edge. There is only a laminar displacement; no mixing occurs. And so the original vertical line is restored when the rotation is reversed.
+There is no violation of the entropy law at work in this demonstration. The spreading out of the ink does not represent any increase in entropy or disorder. An enlarged top view of the space between the two cylinders (see {numref}`Figure {number} <4f1003_figure_2.png>`) shows that molecules on the inner edge of the liquid rotate through angles different from those in the middle or outer edge. There is only a laminar displacement; no mixing occurs. And so the original vertical line is restored when the rotation is reversed.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4f1003_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4f1003/figure_2.png
----
.
```
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/qr_images/qrcode_sqekFe3OHYo_si_qUbX_nqCOMq4QCBF_.svg b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/qr_images/qrcode_sqekFe3OHYo_si_qUbX_nqCOMq4QCBF_.svg
new file mode 100644
index 00000000..67b86a86
--- /dev/null
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F10 Entropy/4F1003 Violation of the Entropy Law/qr_images/qrcode_sqekFe3OHYo_si_qUbX_nqCOMq4QCBF_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3001 Dippy Bird/4F3001.md b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3001 Dippy Bird/4F3001.md
index 89a41182..105d8b7c 100644
--- a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3001 Dippy Bird/4F3001.md
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3001 Dippy Bird/4F3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4f3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4f3001_figure_0.png
+
.
```
@@ -36,12 +35,11 @@ Set up the dippy bird and the beaker as shown in the Diagram. Fill the beaker wi
To the teacher it is very instructive to have the students explain what is happening. So just put the bird in your lecture room and let the students break their brains.
## Explanation
-{numref}`Figure {number} <4f3001/figure_1.png>` shows the system. The bird is filled with a liquid (dichloromethane) having low latent heat of evaporation. Only this liquid and its vapour are inside the bird.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4f3001/figure_1.png
----
+{numref}`Figure {number} <4f3001_figure_1.png>` shows the system. The bird is filled with a liquid (dichloromethane) having low latent heat of evaporation. Only this liquid and its vapour are inside the bird.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4f3001_figure_1.png
+
.
```
Initially the system is at equilibrium. There are two spaces to consider: the head with $n_{h}$ moles of vapour and the abdomen with $n_{a}$ moles of vapour.
@@ -51,18 +49,17 @@ Evaporation of water on the beak outside the head draws heat from inside it; the
The rising fluid raises the centre of mass above the pivot point, so the bird dips. The amount of fluid is set so that at full dip the lower end of the tube is exposed to the vapour. A bubble of vapour rises in the tube and fluid drains into the abdomen. The rising bubble transfers heat to the head. The centre of mass drops below the pivot point and the bird bobs up, oscillating back to its starting position.
Due to this fast swinging movement, there is good evaporation of the water on the beak, and the whole cycle described above repeats itself.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4f3001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4f3001_figure_2.png
+
.
```
-{numref}`Figure {number} <4f3001/figure_2.png>` shows the behaviour of the dippy bird as a heat-engine. Heat flows into the bird at the abdomen and is discarded at the head/beak-side.
+{numref}`Figure {number} <4f3001_figure_2.png>` shows the behaviour of the dippy bird as a heat-engine. Heat flows into the bird at the abdomen and is discarded at the head/beak-side.
### A second bird
-Considering the dippy bird as a heat-engine (see {numref}`Figure {number} <4f3001/figure_2.png>`) induces the idea that it will work as well when, instead of cooling the head, you heat up the abdomen. We tried this by shining light on the dippy's bottom and indeed, the bird dipped! Demonstrating also this version of the dippy bird will once more make clear that the factor that makes heat-engines work is the temperature gradient.
+Considering the dippy bird as a heat-engine (see {numref}`Figure {number} <4f3001_figure_2.png>`) induces the idea that it will work as well when, instead of cooling the head, you heat up the abdomen. We tried this by shining light on the dippy's bottom and indeed, the bird dipped! Demonstrating also this version of the dippy bird will once more make clear that the factor that makes heat-engines work is the temperature gradient.
## Remarks
* We use distilled water instead of tap water, because in our city tap water is hard water and in due time the lime would thermally isolate the beak of the bird.
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/4F3002.md b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/4F3002.md
index 08fd6345..bd38f5b3 100644
--- a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/4F3002.md
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/4F3002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 4f3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 4f3002_figure_0.png
+
.
```
@@ -26,60 +25,40 @@ name: 4f3002/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/3Z4XlAOfLHU?si=JtXd95eKo60muiod
+```
A beaker is filled, almost to the rim with hot tap water (about $50^{\circ} \mathrm{C}$ ). The Stirling engine is placed on top of it (see Diagram A) and after some time the instructor gently spins the flywheel. Try anti-clockwise spin, because then the students will observe that the engine by itself wants to spin clockwise, and so it will do. During the lecture the engine continues spinning.
After some time, halfway your lecture, the instructor places the still running engine on the beaker filled with ice. Very soon the engine slows down and will stop. Some time later the instructor gently tries to spin the flywheel again in a clockwise direction, but to his surprise (?) the engine starts running now in the anti-clockwise direction. During the rest of the lecture-time the engine keeps on running this way.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 4f3002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 4f3002_figure_1.png
+
.
```
-While studying the engine, the "hot"-side, the "cold"-side, the power piston and the displacer are observed (see {numref}`Figure {number} <4f3002/figure_1.png>`) and the similarity with the OHP-model is shown (see Diagram B; yes, upside-down!). The OHP-model is used to explain the principle of operation.
+While studying the engine, the "hot"-side, the "cold"-side, the power piston and the displacer are observed (see {numref}`Figure {number} <4f3002_figure_1.png>`) and the similarity with the OHP-model is shown (see Diagram B; yes, upside-down!). The OHP-model is used to explain the principle of operation.
## Explanation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/mt9k6Xhb_PI?si=kPiQMt8dxbhJ7vy8
+```
Out of the Presentation it is clear that a temperature difference is needed to make the engine run and that the position of "hot" and "cold" determines the direction of rotation.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 4f3002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 4f3002_figure_2.png
+
.
```
-See {numref}`Figure {number} <4f3002/figure_2.png>`A. As the displacer moves away from the warmer side, air flows around the displacer to the warmer side and is heated.
+See {numref}`Figure {number} <4f3002_figure_2.png>`A. As the displacer moves away from the warmer side, air flows around the displacer to the warmer side and is heated.
-{numref}`Figure {number} <4f3002/figure_2.png>`B. When the air is heated, it expands, which increases the pressure. This increase in pressure pushes up the power piston.
+{numref}`Figure {number} <4f3002_figure_2.png>`B. When the air is heated, it expands, which increases the pressure. This increase in pressure pushes up the power piston.
-Figure2C. The energy stored in the flywheel moves the displacer to the warm side of the engine and the air once again flows around the displacer to the cold side of the engine. {numref}`Figure {number} <4f3002/figure_2.png>`A. When the air is cooled the pressure drops and this will pull down the power piston, the displacer moves back to the cold side, the air is displaced to the warm side, and the cycle starts all over again.
+Figure2C. The energy stored in the flywheel moves the displacer to the warm side of the engine and the air once again flows around the displacer to the cold side of the engine. {numref}`Figure {number} <4f3002_figure_2.png>`A. When the air is cooled the pressure drops and this will pull down the power piston, the displacer moves back to the cold side, the air is displaced to the warm side, and the cycle starts all over again.
The displacer only moves the air back and forth from the warm side to the cold side of the engine.
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_3Z4XlAOfLHU_si_JtXd95eKo60muiod_.svg b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_3Z4XlAOfLHU_si_JtXd95eKo60muiod_.svg
new file mode 100644
index 00000000..d3e64182
--- /dev/null
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_3Z4XlAOfLHU_si_JtXd95eKo60muiod_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_mt9k6Xhb_PI_si_kPiQMt8dxbhJ7vy8_.svg b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_mt9k6Xhb_PI_si_kPiQMt8dxbhJ7vy8_.svg
new file mode 100644
index 00000000..a47a5219
--- /dev/null
+++ b/book/book/4 thermodynamics/4F entropy and the second law/4F30 Heat Cycles/4F3002 Stirling Engine/qr_images/qrcode_mt9k6Xhb_PI_si_kPiQMt8dxbhJ7vy8_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5A electrostatics/5A10 Producing Static Charge/5A1001 E Field in Material/5A1001.md b/book/book/5 EM/5A electrostatics/5A10 Producing Static Charge/5A1001 E Field in Material/5A1001.md
index 3cbe9b19..56a5d03e 100644
--- a/book/book/5 EM/5A electrostatics/5A10 Producing Static Charge/5A1001 E Field in Material/5A1001.md
+++ b/book/book/5 EM/5A electrostatics/5A10 Producing Static Charge/5A1001 E Field in Material/5A1001.md
@@ -8,11 +8,10 @@ To discuss with students the phenomenon shown. It seems easy at first thought bu
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a1001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a1001_figure_0
+
.
```
@@ -25,13 +24,12 @@ name: 5a1001/figure_0
## Presentation
The teacher asks the students to reflect about what will happen to neutral soap bubbles that come in the neighborhood of a running Van de Graaff generator. After their ideas are discussed, and some predictions made, the Van de Graaff generator is switched on. The ground lead is plunged into the soap solution and at a distance of around 1.5-2 meters soap bubbles are blown into the direction of the generator.
-The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a1001/figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a1001_figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a1001_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a1001/figure_1
----
.
```
@@ -41,13 +39,12 @@ The other bubbles that are still on their way towards the dome are now pushed aw
The blown bubbles are neutral and they are polarized in the E-field of the dome. Since this field is divergent, a polarized bubble is attracted and accelerated. On contact, the bubble obtains the charge of the dome and when the bubble survives it will be repelled from it (bounces). But when the bubble breaks it will break up as a very fine spray of very fine droplets all having the same charge as the dome and moving fast because of their very small size. This charged spray charges the other bubbles, that are still approaching, and these bubbles becoming charged by the spray they will be repelled now as well.
## Remarks
- * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a1001/figure_2>`).
+ * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a1001_figure_2>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a1001_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a1001/figure_2
----
.
```
diff --git a/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2001 Coulombs Law/5A2001.md b/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2001 Coulombs Law/5A2001.md
index 8f8102a6..ccfea3ab 100644
--- a/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2001 Coulombs Law/5A2001.md
+++ b/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2001 Coulombs Law/5A2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a2001_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ The balls are hanging and touch each other. The shadow of the ping-pong balls is
By means of the Van de Graaff generator the two balls are charged and immediately they separate by electrostatic repulsion. While the shadows of the two balls are dancing around towards their equilibrium, the method of the demonstration is explained to the students and to them it is shown that when we suppose the power in Coulomb's law (1785) is really -2 , the determined distance-ratio should be $2^{1 / 3}=1.259$ (see Explanation). When the two balls have come to rest, the centres of the shadows of the balls are chalk-marked on the blackboard.
-Now the two threads are sandwiched at the halfway point by means of a sliding piece of tape. (This tape is fixed to the threads already before you start the experiment; see {numref}`Figure {number} <5a2001/figure_1.png>`.)
+Now the two threads are sandwiched at the halfway point by means of a sliding piece of tape. (This tape is fixed to the threads already before you start the experiment; see {numref}`Figure {number} <5a2001_figure_1.png>`.)
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a2001/figure_1.png
----
.
```
@@ -52,12 +50,11 @@ That's why it is very fundamental that measurements around Coulomb's law are sti
## Explanation
-{numref}`Figure {number} <5a2001/figure_2.png>` shows that in the equilibrium position: $F_{\text {coulomb }}=m g \tan \varphi$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a2001/figure_2.png
----
+{numref}`Figure {number} <5a2001_figure_2.png>` shows that in the equilibrium position: $F_{\text {coulomb }}=m g \tan \varphi$.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a2001_figure_2.png
+
.
```
diff --git a/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2002 E Field in Material/5A2002.md b/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2002 E Field in Material/5A2002.md
index 55beb8d3..e479065b 100644
--- a/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2002 E Field in Material/5A2002.md
+++ b/book/book/5 EM/5A electrostatics/5A20 Coulombs Law/5A2002 E Field in Material/5A2002.md
@@ -8,11 +8,10 @@ To discuss with students the phenomenon shown. It seems easy at first thought bu
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a2002/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a2002_figure_0
+
.
```
@@ -25,13 +24,12 @@ name: 5a2002/figure_0
## Presentation
The teacher asks the students to reflect about what will happen to neutral soap bubbles that come in the neighborhood of a running Van de Graaff generator. After their ideas are discussed, and some predictions made, the Van de Graaff generator is switched on. The ground lead is plunged into the soap solution and at a distance of around 1.5-2 meters soap bubbles are blown into the direction of the generator.
-The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a2002/figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a2002_figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a2002_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a2002/figure_1
----
.
```
@@ -41,13 +39,12 @@ The other bubbles that are still on their way towards the dome are now pushed aw
The blown bubbles are neutral and they are polarized in the E-field of the dome. Since this field is divergent, a polarized bubble is attracted and accelerated. On contact, the bubble obtains the charge of the dome and when the bubble survives it will be repelled from it (bounces). But when the bubble breaks it will break up as a very fine spray of very fine droplets all having the same charge as the dome and moving fast because of their very small size. This charged spray charges the other bubbles, that are still approaching, and these bubbles becoming charged by the spray they will be repelled now as well.
## Remarks
- * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a2002/figure_2>`).
+ * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a2002_figure_2>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a2002_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a2002/figure_2
----
.
```
\ No newline at end of file
diff --git a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4001 Charging by Induction/5A4001.md b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4001 Charging by Induction/5A4001.md
index f8837e7d..392f75b9 100644
--- a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4001 Charging by Induction/5A4001.md
+++ b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4001 Charging by Induction/5A4001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a4001_figure_0.png
+
.
```
@@ -30,25 +29,23 @@ Shortly, the copper plates with scraps are grounded. Then we rub the rubber stic
Again the rubber stick is rubbed with the cat fur. Now the rubbed stick approaches the scraps of aluminum. Many of them are attracted (not all) and most of them fly away with high speeds when touching the rubber. Also will some of them stick to the rubber.
## Explanation
-The scraps of paper and aluminum are neutral in the beginning. Rubbing the stick charges it negatively and on approaching the paper scraps it induces a polarization in them. The scraps of paper, being insulators are polarized locally. The stick, being charged negatively, redistributes the charge in the neutral "paper-molecules" so that closest to the stick the "paper-molecules" have a net positive charge and on the other side an equally large positive charge (A double overhead sheet can help to explain this: see the demonstration "Polarizing a dielectric" in this database). This results in the piece of scrap being positive on one side and negative on the other. The stick attracts the positive side and repels the negative side of the paper scrap. Applying Coulomb's law shows that due to the $r^{-2}$ relationship the attraction is stronger than the repulsion and the piece of scrap is attracted (see {numref}`Figure {number} <5a4001/figure_1.png>`A).
+The scraps of paper and aluminum are neutral in the beginning. Rubbing the stick charges it negatively and on approaching the paper scraps it induces a polarization in them. The scraps of paper, being insulators are polarized locally. The stick, being charged negatively, redistributes the charge in the neutral "paper-molecules" so that closest to the stick the "paper-molecules" have a net positive charge and on the other side an equally large positive charge (A double overhead sheet can help to explain this: see the demonstration "Polarizing a dielectric" in this database). This results in the piece of scrap being positive on one side and negative on the other. The stick attracts the positive side and repels the negative side of the paper scrap. Applying Coulomb's law shows that due to the $r^{-2}$ relationship the attraction is stronger than the repulsion and the piece of scrap is attracted (see {numref}`Figure {number} <5a4001_figure_1.png>`A).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a4001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a4001/figure_1.png
----
.
```
In case of the aluminum scraps a similar mechanism is at work, but now the free electrons in the aluminum do the job of charge distribution. The negatively charged rubber stick repels the free electrons in the piece of aluminum scrap to the far side and so the piece of scrap becomes polarized. Again Coulomb's law shows that the resulting force is attracting. When the aluminum scraps hit the rubber stick they are generally launched away from the stick: There must be a strong repulsive force at contact; charges have to be equal now.
-This can be explained in supposing that free electrons move from the surface of the rubber stick into the aluminum scrap (that is still positive on that side just before contact to the rubber rod) and locally the rubber is neutralized. The piece of scrap, having gained electrons now has a net negative charge and, being close to a surrounding of negative charge, is strongly repelled (see {numref}`Figure {number} <5a4001/figure_2.png>`).
+This can be explained in supposing that free electrons move from the surface of the rubber stick into the aluminum scrap (that is still positive on that side just before contact to the rubber rod) and locally the rubber is neutralized. The piece of scrap, having gained electrons now has a net negative charge and, being close to a surrounding of negative charge, is strongly repelled (see {numref}`Figure {number} <5a4001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a4001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a4001/figure_2.png
----
.
```
diff --git a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4002 Polarising a Dielectric/5A4002.md b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4002 Polarising a Dielectric/5A4002.md
index 0437e890..c25baa3a 100644
--- a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4002 Polarising a Dielectric/5A4002.md
+++ b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4002 Polarising a Dielectric/5A4002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a4002_figure_0.png
+
.
```
@@ -27,13 +26,12 @@ The overheadsheet with the capacitor plates drawn on it is actually a sleeve, in
## Presentation
-The assembly of overheadsheets is projected: The two sheets with the opposite charges are placed between the capacitor plates such that the plus - and minus signs cover each other (the molecules are no dipoles) (See Diagram A and {numref}`Figure {number} <5a4002/figure_1.png>`).
+The assembly of overheadsheets is projected: The two sheets with the opposite charges are placed between the capacitor plates such that the plus - and minus signs cover each other (the molecules are no dipoles) (See Diagram A and {numref}`Figure {number} <5a4002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a4002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a4002/figure_1.png
----
.
```
diff --git a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4003 E Field in Material/5A4003.md b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4003 E Field in Material/5A4003.md
index 3ec9ac00..b921c6be 100644
--- a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4003 E Field in Material/5A4003.md
+++ b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4003 E Field in Material/5A4003.md
@@ -8,11 +8,10 @@ To discuss with students the phenomenon shown. It seems easy at first thought bu
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a4003/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a4003_figure_0
+
.
```
@@ -25,13 +24,12 @@ name: 5a4003/figure_0
## Presentation
The teacher asks the students to reflect about what will happen to neutral soap bubbles that come in the neighborhood of a running Van de Graaff generator. After their ideas are discussed, and some predictions made, the Van de Graaff generator is switched on. The ground lead is plunged into the soap solution and at a distance of around 1.5-2 meters soap bubbles are blown into the direction of the generator.
-The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a4003/figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+The bubbles are clearly attracted towards the dome of the generator; they are accelerated (when coming close to the dome even their shape changes, see {numref}`Figure {number} <5a4003_figure_1>`). The first bubble hits the dome and explodes (occasionally it remains intact and bounces).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a4003_figure_1
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a4003/figure_1
----
.
```
@@ -41,13 +39,12 @@ The other bubbles that are still on their way towards the dome are now pushed aw
The blown bubbles are neutral and they are polarized in the E-field of the dome. Since this field is divergent, a polarized bubble is attracted and accelerated. On contact, the bubble obtains the charge of the dome and when the bubble survives it will be repelled from it (bounces). But when the bubble breaks it will break up as a very fine spray of very fine droplets all having the same charge as the dome and moving fast because of their very small size. This charged spray charges the other bubbles, that are still approaching, and these bubbles becoming charged by the spray they will be repelled now as well.
## Remarks
- * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a4003/figure_2>`).
+ * That a very fine spray occurs can be observed in a separate, individual experiment in which you make a drop of water fall on the charged dome and in your face you feel a refreshing fine haze (see {numref}`Figure {number} <5a4003_figure_2>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a4003_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a4003/figure_2
----
.
```
\ No newline at end of file
diff --git a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4004 Water Dropper/5A4004.md b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4004 Water Dropper/5A4004.md
index e7341789..519bd486 100644
--- a/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4004 Water Dropper/5A4004.md
+++ b/book/book/5 EM/5A electrostatics/5A40 Induced Charge/5A4004 Water Dropper/5A4004.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a4004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a4004_figure_0.png
+
.
```
@@ -24,7 +23,7 @@ name: 5a4004/figure_0.png
- Metal container with pinchcock, allowing water to drip. (The holding bar is partly made of perspex for isolation.)
- Power supply (about $1 \mathrm{kV}$ ).
- Camera.
-- Electrostatic Voltmeter (see Remarks and {numref}`Figure {number} <5a4004/figure_2.png>`).
+- Electrostatic Voltmeter (see Remarks and {numref}`Figure {number} <5a4004_figure_2.png>`).
## Presentation
@@ -39,15 +38,14 @@ When now the collar is moved away from the falling drops of water, the electrosc
## Explanation
In the first part of the demonstration an electric field ( $1 \mathrm{kV}$ over $10 \mathrm{~cm}$, so $\mathrm{E}=10 \mathrm{kV} / \mathrm{m}$ ) exists between the upper water container and the electroscope.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a4004/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a4004_figure_1.png
+
.
```
-Due to this field, the drops of water will be charged when they break loose from the metal dropper (see {numref}`Figure {number} <5a4004/figure_1.png>`). When the drops fall into the beaker on the electroscope this charge accumulates (on the outside of the beaker) and the deflection of the electroscope increases. This continues until the potential of the beaker is the same as the potential of the upper water container, because now there is no longer an electric field to charge the drops of water.
+Due to this field, the drops of water will be charged when they break loose from the metal dropper (see {numref}`Figure {number} <5a4004_figure_1.png>`). When the drops fall into the beaker on the electroscope this charge accumulates (on the outside of the beaker) and the deflection of the electroscope increases. This continues until the potential of the beaker is the same as the potential of the upper water container, because now there is no longer an electric field to charge the drops of water.
When the grounded metal collar is placed around the stream of falling drops, there will be an electric field again between the collar and the upper water container and again the drops of water will be charged, and again the deflection of the electroscope increases. As long as drops of water fall, the charge on the electroscope increases!
@@ -55,12 +53,11 @@ When now the collar is removed, the electric field between the beaker and contai
## Remarks
- By means of a camera the (reading of the) electroscope is projected on a monitor or large screen.
-- The electroscope can be replaced by an electrostatic Voltmeter (see {numref}`Figure {number} <5a4004/figure_2.png>`). Then the students can see directly that the voltage of the metal beaker can reach a voltage much higher than the voltage of the container from where the drops are falling.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a4004/figure_2.png
----
+- The electroscope can be replaced by an electrostatic Voltmeter (see {numref}`Figure {number} <5a4004_figure_2.png>`). Then the students can see directly that the voltage of the metal beaker can reach a voltage much higher than the voltage of the container from where the drops are falling.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a4004_figure_2.png
+
.
```
diff --git a/book/book/5 EM/5A electrostatics/5A50 Electrostatic Machines/5A5001 Water Dropper/5A5001.md b/book/book/5 EM/5A electrostatics/5A50 Electrostatic Machines/5A5001 Water Dropper/5A5001.md
index d5971243..790aa606 100644
--- a/book/book/5 EM/5A electrostatics/5A50 Electrostatic Machines/5A5001 Water Dropper/5A5001.md
+++ b/book/book/5 EM/5A electrostatics/5A50 Electrostatic Machines/5A5001 Water Dropper/5A5001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5a5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5a5001_figure_0.png
+
.
```
@@ -24,7 +23,7 @@ name: 5a5001/figure_0.png
- Metal container with pinchcock, allowing water to drip. (The holding bar is partly made of perspex for isolation.)
- Power supply (about $1 \mathrm{kV}$ ).
- Camera.
-- Electrostatic Voltmeter (see Remarks and {numref}`Figure {number} <5a5001/figure_2.png>`).
+- Electrostatic Voltmeter (see Remarks and {numref}`Figure {number} <5a5001_figure_2.png>`).
## Presentation
@@ -39,14 +38,13 @@ When now the collar is moved away from the falling drops of water, the electrosc
## Explanation
In the first part of the demonstration an electric field ( $1 \mathrm{kV}$ over $10 \mathrm{~cm}$, so $\mathrm{E}=10 \mathrm{kV} / \mathrm{m}$ ) exists between the upper water container and the electroscope.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5a5001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5a5001_figure_1.png
+
.
```
-Due to this field, the drops of water will be charged when they break loose from the metal dropper (see {numref}`Figure {number} <5a5001/figure_1.png>`). When the drops fall into the beaker on the electroscope this charge accumulates (on the outside of the beaker) and the deflection of the electroscope increases. This continues until the potential of the beaker is the same as the potential of the upper water container, because now there is no longer an electric field to charge the drops of water.
+Due to this field, the drops of water will be charged when they break loose from the metal dropper (see {numref}`Figure {number} <5a5001_figure_1.png>`). When the drops fall into the beaker on the electroscope this charge accumulates (on the outside of the beaker) and the deflection of the electroscope increases. This continues until the potential of the beaker is the same as the potential of the upper water container, because now there is no longer an electric field to charge the drops of water.
When the grounded metal collar is placed around the stream of falling drops, there will be an electric field again between the collar and the upper water container and again the drops of water will be charged, and again the deflection of the electroscope increases. As long as drops of water fall, the charge on the electroscope increases!
@@ -54,12 +52,11 @@ When now the collar is removed, the electric field between the beaker and contai
## Remarks
- By means of a camera the (reading of the) electroscope is projected on a monitor or large screen.
-- The electroscope can be replaced by an electrostatic Voltmeter (see {numref}`Figure {number} <5a5001/figure_2.png>`). Then the students can see directly that the voltage of the metal beaker can reach a voltage much higher than the voltage of the container from where the drops are falling.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5a5001/figure_2.png
----
+- The electroscope can be replaced by an electrostatic Voltmeter (see {numref}`Figure {number} <5a5001_figure_2.png>`). Then the students can see directly that the voltage of the metal beaker can reach a voltage much higher than the voltage of the container from where the drops are falling.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5a5001_figure_2.png
+
.
```
\ No newline at end of file
diff --git a/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1001 Charge and Field/5B1001.md b/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1001 Charge and Field/5B1001.md
index 9dc752f8..96e1c832 100644
--- a/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1001 Charge and Field/5B1001.md
+++ b/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1001 Charge and Field/5B1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5b1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5b1001_figure_0.png
+
.
```
@@ -42,19 +41,18 @@ The demonstrator takes one of the small conducting spheres and touches with that
### Demo 1b
The same demonstration is performed but now the metal pan is charged by touching the inside of the metal pan with the lead coming from the Van de Graaff generator. The result of this demo is exactly the same as in Demo 1a.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5b1001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5b1001_figure_1.png
+
.
```
### Demo 2
-The demonstrator holds the two metal spheres that are touching each other and lowers them into the pan. He takes care that the spheres do not to touch the inside of the pan. Inside the pan he separates the two spheres (see {numref}`Figure {number} <5b1001/figure_1.png>`B), lifts them out of the pan and with one of the spheres he touches the electroscope. The electroscope does not react. Also when he touches the electroscope with the other sphere nothing will happen.
+The demonstrator holds the two metal spheres that are touching each other and lowers them into the pan. He takes care that the spheres do not to touch the inside of the pan. Inside the pan he separates the two spheres (see {numref}`Figure {number} <5b1001_figure_1.png>`B), lifts them out of the pan and with one of the spheres he touches the electroscope. The electroscope does not react. Also when he touches the electroscope with the other sphere nothing will happen.
-He repeats the demonstration, but now he brings the two touching spheres close to the outside of the charged metal pan and there he separates the two spheres (see {numref}`Figure {number} <5b1001/figure_1.png>`A). Again he touches with one sphere the electroscope and now the electroscope shows a deflection. Next, he touches the electroscope with the other metal sphere and the deflection of the electroscope becomes less.
+He repeats the demonstration, but now he brings the two touching spheres close to the outside of the charged metal pan and there he separates the two spheres (see {numref}`Figure {number} <5b1001_figure_1.png>`A). Again he touches with one sphere the electroscope and now the electroscope shows a deflection. Next, he touches the electroscope with the other metal sphere and the deflection of the electroscope becomes less.
## Explanation
The first demonstration shows clearly that charge is always on the outside of the metal pan. Theoretically this can be explained when you apply Gauss's law (see the demonstration [Charge is on the outside](../5B1002%20Charge%20is%20on%20the%20Outside/5B1002.md)
diff --git a/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1002 Charge is on the Outside/5B1002.md b/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1002 Charge is on the Outside/5B1002.md
index d4264150..ccfbca1d 100644
--- a/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1002 Charge is on the Outside/5B1002.md
+++ b/book/book/5 EM/5B electric fields and potential/5B10 Electric Fields/5B1002 Charge is on the Outside/5B1002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5b1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5b1002_figure_0.png
+
.
```
@@ -27,24 +26,22 @@ The two metal hemispheres (sieves) are placed on the styrofoam blocks and placed
The students are asked to predict what will happen to the electroscope when the metal sphere is charged.
-The Van de Graaff generator is switched on and charges the closed metal sphere. The electroscope inside shows no deflection (see {numref}`Figure {number} <5b1002/figure_1.png>`).
+The Van de Graaff generator is switched on and charges the closed metal sphere. The electroscope inside shows no deflection (see {numref}`Figure {number} <5b1002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5b1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5b1002/figure_1.png
----
.
```
Now students are asked to predict what will happen to the electroscope when the charged metal sphere is separated into two halves.
-The sphere is opened by pulling one sieve away (pulling the styrofoam block) and immediately the electroscope shows a deflection (see {numref}`Figure {number} <5b1002/figure_2.png>`). Closing the metal sphere again makes the deflection of the electroscope zero again.
+The sphere is opened by pulling one sieve away (pulling the styrofoam block) and immediately the electroscope shows a deflection (see {numref}`Figure {number} <5b1002_figure_2.png>`). Closing the metal sphere again makes the deflection of the electroscope zero again.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5b1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5b1002/figure_2.png
----
.
```
.
diff --git a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2001 Gauss Law/5B2001.md b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2001 Gauss Law/5B2001.md
index 3608de35..613d3fb6 100644
--- a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2001 Gauss Law/5B2001.md
+++ b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2001 Gauss Law/5B2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5b2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5b2001_figure_0.png
+
.
```
@@ -40,11 +39,10 @@ The continuity-relation between the volume rate of flow, $f(f=\Delta V / \Delta
In case of three-dimensional flow the area $A$ considered equals $4 \pi r^{2}$ giving $4 \pi r^{2} v=$ constant leading to the $1 / r^{2}$ dependence.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5b2001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5b2001_figure_1.png
+
.
```
@@ -53,14 +51,13 @@ name: 5b2001/figure_1.png
- The support for the separating funnel is not fixed to the overhead projector but to a separate table (see Diagram). This is done on purpose, because otherwise adjusting the dripping of the funnel makes the assembly shaking and that will disturb the observed fluid flow.
- Instead of an overhead projector also a camera can be used to show the fluid flow.
-- Filling the flexible tubing of $50 \mathrm{~cm}$ is done by using two Hoffman clamps (see {numref}`Figure {number} <5b2001/figure_2.png>`).
+- Filling the flexible tubing of $50 \mathrm{~cm}$ is done by using two Hoffman clamps (see {numref}`Figure {number} <5b2001_figure_2.png>`).
- Take care that no air bubbles are in the fluid between the two circular plates. (We use a piece of overhead-sheet to wipe away bubbles.)
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5b2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5b2001_figure_2.png
+
.
```
diff --git a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2002 Charge is on the Outside/5B2002.md b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2002 Charge is on the Outside/5B2002.md
index 63d6eef6..2932771f 100644
--- a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2002 Charge is on the Outside/5B2002.md
+++ b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2002 Charge is on the Outside/5B2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5b2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5b2002_figure_0.png
+
.
```
@@ -27,24 +26,22 @@ The two metal hemispheres (sieves) are placed on the styrofoam blocks and placed
The students are asked to predict what will happen to the electroscope when the metal sphere is charged.
-The Van de Graaff generator is switched on and charges the closed metal sphere. The electroscope inside shows no deflection (see {numref}`Figure {number} <5b2002/figure_1.png>`).
+The Van de Graaff generator is switched on and charges the closed metal sphere. The electroscope inside shows no deflection (see {numref}`Figure {number} <5b2002_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5b2002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5b2002/figure_1.png
----
.
```
Now students are asked to predict what will happen to the electroscope when the charged metal sphere is separated into two halves.
-The sphere is opened by pulling one sieve away (pulling the styrofoam block) and immediately the electroscope shows a deflection (see {numref}`Figure {number} <5b2002/figure_2.png>`). Closing the metal sphere again makes the deflection of the electroscope zero again.
+The sphere is opened by pulling one sieve away (pulling the styrofoam block) and immediately the electroscope shows a deflection (see {numref}`Figure {number} <5b2002_figure_2.png>`). Closing the metal sphere again makes the deflection of the electroscope zero again.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5b2002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5b2002/figure_2.png
----
.
```
.
diff --git a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2003 Charge and Field/5B2003.md b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2003 Charge and Field/5B2003.md
index db615daa..bf944980 100644
--- a/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2003 Charge and Field/5B2003.md
+++ b/book/book/5 EM/5B electric fields and potential/5B20 Gauss Law/5B2003 Charge and Field/5B2003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5b2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5b2003_figure_0.png
+
.
```
@@ -41,19 +40,18 @@ The demonstrator takes one of the small conducting spheres and touches with that
### Demo 1b
The same demonstration is performed but now the metal pan is charged by touching the inside of the metal pan with the lead coming from the Van de Graaff generator. The result of this demo is exactly the same as in Demo 1a.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5b2003/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5b2003_figure_1.png
+
.
```
### Demo 2
-The demonstrator holds the two metal spheres that are touching each other and lowers them into the pan. He takes care that the spheres do not to touch the inside of the pan. Inside the pan he separates the two spheres (see {numref}`Figure {number} <5b2003/figure_1.png>`B), lifts them out of the pan and with one of the spheres he touches the electroscope. The electroscope does not react. Also when he touches the electroscope with the other sphere nothing will happen.
+The demonstrator holds the two metal spheres that are touching each other and lowers them into the pan. He takes care that the spheres do not to touch the inside of the pan. Inside the pan he separates the two spheres (see {numref}`Figure {number} <5b2003_figure_1.png>`B), lifts them out of the pan and with one of the spheres he touches the electroscope. The electroscope does not react. Also when he touches the electroscope with the other sphere nothing will happen.
-He repeats the demonstration, but now he brings the two touching spheres close to the outside of the charged metal pan and there he separates the two spheres (see {numref}`Figure {number} <5b2003/figure_1.png>`A). Again he touches with one sphere the electroscope and now the electroscope shows a deflection. Next, he touches the electroscope with the other metal sphere and the deflection of the electroscope becomes less.
+He repeats the demonstration, but now he brings the two touching spheres close to the outside of the charged metal pan and there he separates the two spheres (see {numref}`Figure {number} <5b2003_figure_1.png>`A). Again he touches with one sphere the electroscope and now the electroscope shows a deflection. Next, he touches the electroscope with the other metal sphere and the deflection of the electroscope becomes less.
## Explanation
The first demonstration shows clearly that charge is always on the outside of the metal pan. Theoretically this can be explained when you apply Gauss's law (see the demonstration [Charge is on the outside](../../5B10%20Electric%20Fields/5B1002%20Charge%20is%20on%20the%20Outside/5B1002.md).
diff --git a/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/5C1020.md b/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/5C1020.md
index 5fdea47f..50b8759b 100644
--- a/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/5C1020.md
+++ b/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/5C1020.md
@@ -12,11 +12,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: figures/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: figures_figure_0.png
+
.
```
@@ -31,19 +30,17 @@ name: figures/figure_0.png
## Presentation
The students are told that in this demonstration we will measure the voltage across a charged capacitor. Measuring this voltage is done by an electroscope. A "normal" moving coil meter cannot be used for this measurement, since such an instrument discharges the capacitor immediately (if needed you can show this: charge the capacitor with the power supply, apply the kV-meter and measure … nothing). So, the first thing to do in this demonstration is to show that the electroscope can be used as a voltmeter. The demonstration is set up as shown in Figure1A (DiagramA).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: figures/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: figures_figure_1.png
+
.
```
Just show that when when you change the voltage of the power supply, the kV-meter and the electroscope move synchronously. It is easy to conclude that the electroscope can be used as a voltmeter. Next, the circuit is build as shown in Figure1B. The distance d between the plates is set at a minimum. The capacitor is charged by touching the circuit at A, for a short moment, by the power supply. The electroscope shows a medium deflection. Ask the students what will happen with the deflection of the electroscope when the distance between the capacitor plates is increased. When they have answered this question, do the demonstration and they will see that the voltage increases. (To most students this is counterintuitive.) Capacitor: spacing and dielectric
-```{figure} figures/figure_2.png
----
-width: 70%
-name: figures/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: figures_figure_2.png
+
.
```
In the last part of the demonstration the influence of different dielectrics is shown. The capacitor is placed in front of an improvised guiding construction (see Figure2A). The capacitor is given a separation d, just a little bit larger than the thickness of the glass plate. The capacitor is charged by means of the power supply; the electroscope shows a medium deflection. Ask the students what will happen when the glass plate is shifted between the capacitor plates. When they have given their answers shift the plate between the plates and they will see that the voltage lowers. The same demonstration can be performed by shifting the container with water between the capacitor plates (see Figure2B). Capacitor: spacing and dielectric
@@ -59,7 +56,6 @@ name: figures/figure_2.png
```{iframe} https://www.youtube.com/watch?v=0hbJdk7mg_Y
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/qr_images/qrcode_watch_v_0hbJdk7mg_Y.svg b/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/qr_images/qrcode_watch_v_0hbJdk7mg_Y.svg
new file mode 100644
index 00000000..d92c658b
--- /dev/null
+++ b/book/book/5 EM/5C capacitance/5C10 Capacitors/5C1020 Capacitor Spacing between the Plates/qr_images/qrcode_watch_v_0hbJdk7mg_Y.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2001 Polarising a Dielectric/5C2001.md b/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2001 Polarising a Dielectric/5C2001.md
index 0ff33b16..e9ec8e4a 100644
--- a/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2001 Polarising a Dielectric/5C2001.md
+++ b/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2001 Polarising a Dielectric/5C2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5c2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5c2001_figure_0.png
+
.
```
@@ -27,13 +26,12 @@ The overheadsheet with the capacitor plates drawn on it is actually a sleeve, in
## Presentation
-The assembly of overheadsheets is projected: The two sheets with the opposite charges are placed between the capacitor plates such that the plus - and minus signs cover each other (the molecules are no dipoles) (See Diagram A and {numref}`Figure {number} <5c2001/figure_1.png>`).
+The assembly of overheadsheets is projected: The two sheets with the opposite charges are placed between the capacitor plates such that the plus - and minus signs cover each other (the molecules are no dipoles) (See Diagram A and {numref}`Figure {number} <5c2001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5c2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5c2001/figure_1.png
----
.
```
diff --git a/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2002 Capacitor/5C2002.md b/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2002 Capacitor/5C2002.md
index fe759709..ebd3771e 100644
--- a/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2002 Capacitor/5C2002.md
+++ b/book/book/5 EM/5C capacitance/5C20 Dielectric/5C2002 Capacitor/5C2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5c2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5c2002_figure_0.png
+
.
```
@@ -22,7 +21,7 @@ name: 5c2002/figure_0.png
- Electrostatic voltmeter, $0-25 \mathrm{kV}$.
- Glass plate, thickness $20 \mathrm{~mm}$.
- Perspex container, $50 \times 30 \times 3 \mathrm{~cm}^{3}$, filled with demineralized water.
-- Wooden bar as a guiding construction (very well visible in {numref}`Figure {number} <5c2002/figure_2.png>`).
+- Wooden bar as a guiding construction (very well visible in {numref}`Figure {number} <5c2002_figure_2.png>`).
- Power supply, $0-6 \mathrm{kV}$ (see Safety). For the demonstration it is better to use a $25 \mathrm{kV}$ power supply, set at $15 \mathrm{kV}$
- Use connection leads with Teflon isolation.
- Electric heater (to prevent that moisture spoils the demonstration).
@@ -35,30 +34,27 @@ name: 5c2002/figure_0.png
## Presentation
The setup of the demonstration is explained to the students. The plates are set at such a separation that $d$ just a little bit larger than the thickness of the glass-plate. The power supply is set at $15 \mathrm{kV}$.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5c2002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5c2002_figure_1.png
+
.
```
-The capacitor is charged by shortly touching the capacitor with the free lead of the $15 \mathrm{kV}$ power supply (see {numref}`Figure {number} <5c2002/figure_1.png>`). After this charging of the capacitor, the voltmeter reads $15 \mathrm{kV}$.
+The capacitor is charged by shortly touching the capacitor with the free lead of the $15 \mathrm{kV}$ power supply (see {numref}`Figure {number} <5c2002_figure_1.png>`). After this charging of the capacitor, the voltmeter reads $15 \mathrm{kV}$.
+
+The students are asked what will happen to the voltage of a charged capacitor when the glass plate is shifted between the plates (see {numref}`Figure {number} <5c2002_figure_2.png>`). After their answers shift the glass between the capacitor plates. They will see that the voltage lowers. Shift carefully all the time, with the glass plate sliding along the grounded plate of the capacitor, so the glass plate does not touch the high voltage positive plate!
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5c2002_figure_2.png
-The students are asked what will happen to the voltage of a charged capacitor when the glass plate is shifted between the plates (see {numref}`Figure {number} <5c2002/figure_2.png>`). After their answers shift the glass between the capacitor plates. They will see that the voltage lowers. Shift carefully all the time, with the glass plate sliding along the grounded plate of the capacitor, so the glass plate does not touch the high voltage positive plate!
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5c2002/figure_2.png
----
.
```
-Removing the glass plate will increase the voltage again to its original value of $15 \mathrm{kV}$. The same experiment is performed with the container filled with water (see {numref}`Figure {number} <5c2002/figure_3.png>`).
+Removing the glass plate will increase the voltage again to its original value of $15 \mathrm{kV}$. The same experiment is performed with the container filled with water (see {numref}`Figure {number} <5c2002_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5c2002_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5c2002/figure_3.png
----
.
```
diff --git a/book/book/5 EM/5C capacitance/5C30 Energy stored in a capacitor/5C3001 Capacitor/5C3001.md b/book/book/5 EM/5C capacitance/5C30 Energy stored in a capacitor/5C3001 Capacitor/5C3001.md
index 37a32c17..2121c8b8 100644
--- a/book/book/5 EM/5C capacitance/5C30 Energy stored in a capacitor/5C3001 Capacitor/5C3001.md
+++ b/book/book/5 EM/5C capacitance/5C30 Energy stored in a capacitor/5C3001 Capacitor/5C3001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5c3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5c3001_figure_0.png
+
.
```
@@ -22,7 +21,7 @@ name: 5c3001/figure_0.png
- Electrostatic voltmeter, $0-25 \mathrm{kV}$.
- Glass plate, thickness $20 \mathrm{~mm}$.
- Perspex container, $50 \times 30 \times 3 \mathrm{~cm}^{3}$, filled with demineralized water.
-- Wooden bar as a guiding construction (very well visible in {numref}`Figure {number} <5c3001/figure_2.png>`).
+- Wooden bar as a guiding construction (very well visible in {numref}`Figure {number} <5c3001_figure_2.png>`).
- Power supply, $0-6 \mathrm{kV}$ (see Safety). For the demonstration it is better to use a $25 \mathrm{kV}$ power supply, set at $15 \mathrm{kV}$
- Use connection leads with Teflon isolation.
- Electric heater (to prevent that moisture spoils the demonstration).
@@ -35,30 +34,27 @@ name: 5c3001/figure_0.png
## Presentation
The setup of the demonstration is explained to the students. The plates are set at such a separation that $d$ just a little bit larger than the thickness of the glass-plate. The power supply is set at $15 \mathrm{kV}$.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5c3001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5c3001_figure_1.png
+
.
```
-The capacitor is charged by shortly touching the capacitor with the free lead of the $15 \mathrm{kV}$ power supply (see {numref}`Figure {number} <5c3001/figure_1.png>`). After this charging of the capacitor, the voltmeter reads $15 \mathrm{kV}$.
+The capacitor is charged by shortly touching the capacitor with the free lead of the $15 \mathrm{kV}$ power supply (see {numref}`Figure {number} <5c3001_figure_1.png>`). After this charging of the capacitor, the voltmeter reads $15 \mathrm{kV}$.
+
+The students are asked what will happen to the voltage of a charged capacitor when the glass plate is shifted between the plates (see {numref}`Figure {number} <5c3001_figure_2.png>`). After their answers shift the glass between the capacitor plates. They will see that the voltage lowers. Shift carefully all the time, with the glass plate sliding along the grounded plate of the capacitor, so the glass plate does not touch the high voltage positive plate!
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5c3001_figure_2.png
-The students are asked what will happen to the voltage of a charged capacitor when the glass plate is shifted between the plates (see {numref}`Figure {number} <5c3001/figure_2.png>`). After their answers shift the glass between the capacitor plates. They will see that the voltage lowers. Shift carefully all the time, with the glass plate sliding along the grounded plate of the capacitor, so the glass plate does not touch the high voltage positive plate!
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5c3001/figure_2.png
----
.
```
-Removing the glass plate will increase the voltage again to its original value of $15 \mathrm{kV}$. The same experiment is performed with the container filled with water (see {numref}`Figure {number} <5c3001/figure_3.png>`).
+Removing the glass plate will increase the voltage again to its original value of $15 \mathrm{kV}$. The same experiment is performed with the container filled with water (see {numref}`Figure {number} <5c3001_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5c3001_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5c3001/figure_3.png
----
.
```
diff --git a/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2001 PTC/5D2001.md b/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2001 PTC/5D2001.md
index 64ec90b1..f66fa20b 100644
--- a/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2001 PTC/5D2001.md
+++ b/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2001 PTC/5D2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5d2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5d2001_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2002 NTC/5D2002.md b/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2002 NTC/5D2002.md
index 87f1b190..89026b96 100644
--- a/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2002 NTC/5D2002.md
+++ b/book/book/5 EM/5D resistance/5D20 Resistivity and Temperature/5D2002 NTC/5D2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5d2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5d2002_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5F DC circuits/5F15 Power and Energy/5F1501 Fuse Wires Parallel/5F1501.md b/book/book/5 EM/5F DC circuits/5F15 Power and Energy/5F1501 Fuse Wires Parallel/5F1501.md
index 1311359f..6bee96e1 100644
--- a/book/book/5 EM/5F DC circuits/5F15 Power and Energy/5F1501 Fuse Wires Parallel/5F1501.md
+++ b/book/book/5 EM/5F DC circuits/5F15 Power and Energy/5F1501 Fuse Wires Parallel/5F1501.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5f1501/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5f1501_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ name: 5f1501/figure_0.png
## Presentation
First take the thin fusible NiCr wire. Make a current flow through it. Slowly increase that current and show how the wire starts glowing and finally melts/breaks.
-Set up the demonstration as shown in {numref}`Figure {number} <5f1501/figure_1.png>` and Diagram.
+Set up the demonstration as shown in {numref}`Figure {number} <5f1501_figure_1.png>` and Diagram.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5f1501_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5f1501/figure_1.png
----
.
```
Two brass strips connect the nickel-chromium wires in parallel. Indicate the difference in diameter of the four wires to the students. Ask the students which wire will burn out first, as the voltage between the brass strips increases. (Most students will guess the wrong answer. Guessing possibilities: None of them melts; all melt together at the same time; the thinnest melts first; the thickest melts first; ...) Slowly increase the voltage. Soon the glowing of the wires indicates that the thickest wire will burn out first. The thinner the wire the more voltage is needed to burn it out.
@@ -46,13 +44,12 @@ Two brass strips connect the nickel-chromium wires in parallel. Indicate the dif
## Explanation
In a parallel-circuit the voltage $(V)$ is common to the components. Comparing the power on the components should be done by using $P_{\text {electrical }}=\frac{V^{2}}{R_{\text {component }}}$. Since $V$ is common to all parallel components the difference in $P$ is determined by $R$ : The lower $R$, the higher $P_{e l}$. But it is also true that the thicker $R$, the larger its cooling surface. This counteracts the heating up of the thicker wire. Since $P_{e l}=\frac{V^{2}}{R}$ and $R=\rho \frac{l}{A}=\rho \frac{l}{\frac{\pi d^{2}}{4}}, P_{e l} \propto d^{2}$.
-The power that leaves the wire to its surroundings is proportional to the surface of that wire and the $\Delta T$ to its surroundings (Newton cooling). The cooling surface $S$ equals $\pi d l$ (see {numref}`Figure {number} <5f1501/figure_2.png>`).
+The power that leaves the wire to its surroundings is proportional to the surface of that wire and the $\Delta T$ to its surroundings (Newton cooling). The cooling surface $S$ equals $\pi d l$ (see {numref}`Figure {number} <5f1501_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5f1501_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5f1501/figure_2.png
----
.
```
diff --git a/book/book/5 EM/5F DC circuits/5F20 Circuit Analysis/5F2001 Fuse Wires Parallel/5F2001.md b/book/book/5 EM/5F DC circuits/5F20 Circuit Analysis/5F2001 Fuse Wires Parallel/5F2001.md
index db41b766..7915451b 100644
--- a/book/book/5 EM/5F DC circuits/5F20 Circuit Analysis/5F2001 Fuse Wires Parallel/5F2001.md
+++ b/book/book/5 EM/5F DC circuits/5F20 Circuit Analysis/5F2001 Fuse Wires Parallel/5F2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5f2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5f2001_figure_0.png
+
.
```
@@ -32,13 +31,12 @@ name: 5f2001/figure_0.png
## Presentation
First take the thin fusible NiCr wire. Make a current flow through it. Slowly increase that current and show how the wire starts glowing and finally melts/breaks.
-Set up the demonstration as shown in {numref}`Figure {number} <5f2001/figure_1.png>` and Diagram.
+Set up the demonstration as shown in {numref}`Figure {number} <5f2001_figure_1.png>` and Diagram.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5f2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5f2001/figure_1.png
----
.
```
Two brass strips connect the nickel-chromium wires in parallel. Indicate the difference in diameter of the four wires to the students. Ask the students which wire will burn out first, as the voltage between the brass strips increases. (Most students will guess the wrong answer. Guessing possibilities: None of them melts; all melt together at the same time; the thinnest melts first; the thickest melts first; ...) Slowly increase the voltage. Soon the glowing of the wires indicates that the thickest wire will burn out first. The thinner the wire the more voltage is needed to burn it out.
@@ -46,13 +44,12 @@ Two brass strips connect the nickel-chromium wires in parallel. Indicate the dif
## Explanation
In a parallel-circuit the voltage $(V)$ is common to the components. Comparing the power on the components should be done by using $P_{\text {electrical }}=\frac{V^{2}}{R_{\text {component }}}$. Since $V$ is common to all parallel components the difference in $P$ is determined by $R$ : The lower $R$, the higher $P_{e l}$. But it is also true that the thicker $R$, the larger its cooling surface. This counteracts the heating up of the thicker wire. Since $P_{e l}=\frac{V^{2}}{R}$ and $R=\rho \frac{l}{A}=\rho \frac{l}{\frac{\pi d^{2}}{4}}, P_{e l} \propto d^{2}$.
-The power that leaves the wire to its surroundings is proportional to the surface of that wire and the $\Delta T$ to its surroundings (Newton cooling). The cooling surface $S$ equals $\pi d l$ (see {numref}`Figure {number} <5f2001/figure_2.png>`).
+The power that leaves the wire to its surroundings is proportional to the surface of that wire and the $\Delta T$ to its surroundings (Newton cooling). The cooling surface $S$ equals $\pi d l$ (see {numref}`Figure {number} <5f2001_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5f2001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5f2001/figure_2.png
----
.
```
diff --git a/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2001 Barkhausen Effect/5G2001.md b/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2001 Barkhausen Effect/5G2001.md
index 37fe82d8..b105fa69 100644
--- a/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2001 Barkhausen Effect/5G2001.md
+++ b/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2001 Barkhausen Effect/5G2001.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5g2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5g2001_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2002 Barkhausen Effect/5G2002.md b/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2002 Barkhausen Effect/5G2002.md
index ef596e21..b0ab1814 100644
--- a/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2002 Barkhausen Effect/5G2002.md
+++ b/book/book/5 EM/5G magnetic materials/5G20 Magnet Domains and Magnetization/5G2002 Barkhausen Effect/5G2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5g2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5g2002_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4001 Barkhausen Effect/5G4001.md b/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4001 Barkhausen Effect/5G4001.md
index bb1ea2d2..b11d10f1 100644
--- a/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4001 Barkhausen Effect/5G4001.md
+++ b/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4001 Barkhausen Effect/5G4001.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5g4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5g4001_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4002 Barkhausen Effect/5G4002.md b/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4002 Barkhausen Effect/5G4002.md
index 9d8ed870..351d8d27 100644
--- a/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4002 Barkhausen Effect/5G4002.md
+++ b/book/book/5 EM/5G magnetic materials/5G40 Hysteresis/5G4002 Barkhausen Effect/5G4002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5g4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5g4002_figure_0.png
+
.
```
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H10 Magnetic Fields/5H1001 Magnetic Fields/5H1001.md b/book/book/5 EM/5H magnetic fields and forces/5H10 Magnetic Fields/5H1001 Magnetic Fields/5H1001.md
index 7f13bbcc..6ff40b1c 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H10 Magnetic Fields/5H1001 Magnetic Fields/5H1001.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H10 Magnetic Fields/5H1001 Magnetic Fields/5H1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h1001_figure_0.png
+
.
```
@@ -41,31 +40,29 @@ In the brass rod a current of $100 \mathrm{~A}$ is flowing, supplied by the powe
We create a monopole by placing two long magnets head to tail. In that way, the North- and South pole are far away from each other. So, in the neighborhood of the North pole the influence of the South pole can be neglected.
-First we need to detect where this monopole is situated. The magnet bar is placed on an overhead projector and covered with a plexiglass sheet. Scattering iron filings on the sheet will show the shape of the magnetic field by the orientation of the filings. It is observed that the field lines "originate" from a point about $1 \mathrm{~cm}$ inside the bar magnet (see {numref}`Figure {number} <5h1001/figure_1.png>`).
+First we need to detect where this monopole is situated. The magnet bar is placed on an overhead projector and covered with a plexiglass sheet. Scattering iron filings on the sheet will show the shape of the magnetic field by the orientation of the filings. It is observed that the field lines "originate" from a point about $1 \mathrm{~cm}$ inside the bar magnet (see {numref}`Figure {number} <5h1001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h1001/figure_1.png
----
.
```
Then the magnetic field is measured. The Hall probe is shifted towards the monopole until a deflection of 8 units. The distance away from the monopole is read on the ruler. Then the distance is doubled, and the meter indicates: 2 units. These two measurements illustrate the $R^{2}$ dependence of the magnetic field in this situation.
### Presentation C (see Diagram C)
-As a dipole we use a strong horseshoe magnet. First we indicate from where we measure the distances and which orientation we will use (see {numref}`Figure {number} <5h1001/figure_2.png>`). We start perpendicular to the magnet. The probe is shifted until we measure 8 units on the meter. The distance from the dipole is measured on the ruler. Then we ask the students what will be read from the meter when the distance is doubled.
+As a dipole we use a strong horseshoe magnet. First we indicate from where we measure the distances and which orientation we will use (see {numref}`Figure {number} <5h1001_figure_2.png>`). We start perpendicular to the magnet. The probe is shifted until we measure 8 units on the meter. The distance from the dipole is measured on the ruler. Then we ask the students what will be read from the meter when the distance is doubled.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h1001/figure_2.png
----
.
```
When we measure we come to 1 unit, illustrating the $R^{-3}$ dependence of the $B$-field in case of a dipole.
-The same procedure is followed when $R$ is in the direction of the dipole (this is along the $y$-axis, see {numref}`Figure {number} <5h1001/figure_2.png>`). The same dependence will be found.
+The same procedure is followed when $R$ is in the direction of the dipole (this is along the $y$-axis, see {numref}`Figure {number} <5h1001_figure_2.png>`). The same dependence will be found.
Also any other orientation can be measured with the same result.
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2001 Force between Magnets/5H2001.md b/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2001 Force between Magnets/5H2001.md
index 69ad8b04..418a7ed2 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2001 Force between Magnets/5H2001.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2001 Force between Magnets/5H2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h2001_figure_0.png
+
.
```
@@ -26,18 +25,17 @@ name: 5h2001/figure_0.png
## Presentation
- The U-sections and shelf are set up as shown in Diagram. The magnets can roll freely in the U-profiles. The first magnet is placed in the shelf, stopped by a clamp (see Diagram). Then the second magnet is placed in the U-section. It rolls towards the first magnet, then stops due to repulsion. The set up is bumped gently by hand, in order to reduce the influence of friction on the setting of the distance between the repelling magnets. Then the separation $s$, between the magnets can be read (the audience can do so thanks to the projection by the projector) and the center to center distance (d) is determined by adding $100 \mathrm{~mm}$ to $s$ (see {numref}`Figure {number} <5h2001/figure_1.png>`).
+ The U-sections and shelf are set up as shown in Diagram. The magnets can roll freely in the U-profiles. The first magnet is placed in the shelf, stopped by a clamp (see Diagram). Then the second magnet is placed in the U-section. It rolls towards the first magnet, then stops due to repulsion. The set up is bumped gently by hand, in order to reduce the influence of friction on the setting of the distance between the repelling magnets. Then the separation $s$, between the magnets can be read (the audience can do so thanks to the projection by the projector) and the center to center distance (d) is determined by adding $100 \mathrm{~mm}$ to $s$ (see {numref}`Figure {number} <5h2001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h2001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h2001/figure_1.png
----
.
```
```{table} Measurements
-:name: 5H2001-table1
+:label: 5H2001-table1
| | Number of magnets | $s$ $(\mathrm{mm})$ | $r$ $(\mathrm{mm})$ |
| :---: | :---: | :---: | :---: |
@@ -59,15 +57,14 @@ The first measurement (with two magnets) gives: $F_{1} r_{1}^{m}=c R_{1} R_{2}$.
The second measurement (with three magnets) gives: $F_{2} r_{2}^{m}=c R_{1} R_{2}$.
-Since $F_{2}=2 F_{1}$ (see {numref}`Figure {number} <5h2001/figure_2.png>`), we find: $\frac{r_{1}}{r_{2}}=\sqrt[m]{2}$
+Since $F_{2}=2 F_{1}$ (see {numref}`Figure {number} <5h2001_figure_2.png>`), we find: $\frac{r_{1}}{r_{2}}=\sqrt[m]{2}$
So measuring $r_{1}$ and $r_{2}$, we can determine $m$!
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h2001_figure_2.png
+
.
```
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2002 Force between Magnets/5H2002.md b/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2002 Force between Magnets/5H2002.md
index 662f23c5..7df6e664 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2002 Force between Magnets/5H2002.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H20 Forces on Magnets/5H2002 Force between Magnets/5H2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h2002_figure_0.png
+
.
```
@@ -32,18 +31,17 @@ name: 5h2002/figure_0.png
## Presentation
The demonstration is set up as shown in DiagramA. One force sensor is firmly clamped. Make sure the table stands firmly on the ground. We connect the moving force sensor to the interface. The software is set in such a way that a graph of force versus displacement can be registered. Tare the moving force sensor.
-Start data-acquisition and, by hand, displace the free force sensor quietly towards the clamped one. Take care to hold the moving force sensor along the guiding section. A graph as shown in red in {numref}`Figure {number} <5h2002/figure_1.png>`A will be registered.
+Start data-acquisition and, by hand, displace the free force sensor quietly towards the clamped one. Take care to hold the moving force sensor along the guiding section. A graph as shown in red in {numref}`Figure {number} <5h2002_figure_1.png>`A will be registered.
+
+Clearly can be seen that the force increases rapidly when the magnets approach each other. The curve-fit-option in the software it is tried (power fit). Choosing the region $5-$ to $7.8 \mathrm{~cm}$ a power fit with power 4 is a good option (see {numref}`Figure {number} <5h2002_figure_1.png>`A, the black line).
-Clearly can be seen that the force increases rapidly when the magnets approach each other. The curve-fit-option in the software it is tried (power fit). Choosing the region $5-$ to $7.8 \mathrm{~cm}$ a power fit with power 4 is a good option (see {numref}`Figure {number} <5h2002/figure_1.png>`A, the black line).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h2002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h2002/figure_1.png
----
.
```
-But it can be seen at the same time that for the region from $7.8 \mathrm{~cm}$ to "touching magnets", the power in the formula needs a higher number. Selecting this region and applying $a_{3}=-5.51984$ (line of symmetry in the graph as found in the former selection) we find, by trial and error (trying to make chi^ 2 as low as possible), a power of 6 being more or less a good one (see {numref}`Figure {number} <5h2002/figure_1.png>`B).
+But it can be seen at the same time that for the region from $7.8 \mathrm{~cm}$ to "touching magnets", the power in the formula needs a higher number. Selecting this region and applying $a_{3}=-5.51984$ (line of symmetry in the graph as found in the former selection) we find, by trial and error (trying to make chi^ 2 as low as possible), a power of 6 being more or less a good one (see {numref}`Figure {number} <5h2002_figure_1.png>`B).
## Explanation
The magnets that approach each other are dipoles. It are disc magnets, about $5 \mathrm{~mm}$ thick. Such a magnet is a magnetic dipole. We analyse our demonstration by first looking at the magnetic field produced by one magnetic dipole and next look what will happen when a second dipole is placed in that field.
@@ -52,13 +50,12 @@ Many textbooks show that the magnetic field strength $(H)$ of a dipole depends o
When a second dipole is placed in such a field it experiences a net force, since the field is not uniform and the opposing forces on its North- and Southpole will not cancel.
-{numref}`Figure {number} <5h2002/figure_2.png>`B can be used to explain this: If at $\mathrm{P}$ the magnetic field strength is $H_{x}$, then at $\mathrm{Q}$, for a dipole of length $d x$, it will have the magnitude $H_{x}+d H_{x,}$ or $H_{x}+\frac{d H_{x}}{d x} d x$.
+{numref}`Figure {number} <5h2002_figure_2.png>`B can be used to explain this: If at $\mathrm{P}$ the magnetic field strength is $H_{x}$, then at $\mathrm{Q}$, for a dipole of length $d x$, it will have the magnitude $H_{x}+d H_{x,}$ or $H_{x}+\frac{d H_{x}}{d x} d x$.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h2002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h2002/figure_2.png
----
.
```
@@ -70,7 +67,7 @@ $F_{Q} \propto-\left(H_{x}+\frac{d H_{x}}{d x} d x\right)$
The resultant force on dipole PQ:
-$F_{\text {dipole }} \propto \frac{d H_{x}}{d x}$, so and applying $H \propto r^{-3}$ we get $F \propto r^{-4}$. The result of {numref}`Figure {number} <5h2002/figure_1.png>`A verifies this.
+$F_{\text {dipole }} \propto \frac{d H_{x}}{d x}$, so and applying $H \propto r^{-3}$ we get $F \propto r^{-4}$. The result of {numref}`Figure {number} <5h2002_figure_1.png>`A verifies this.
When the magnets are very close, the expression $r \gg l$ is no longer valid ( $/=2.5 \mathrm{~mm}$ ) and the expression $H \propto r^{-3}$ for the field of the dipole will be different and so the expression for the force between the dipoles will be a different one.
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3001 Force on Electrons in a Magnetic Field/5H3001.md b/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3001 Force on Electrons in a Magnetic Field/5H3001.md
index c3ebc5d7..48d7c7a9 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3001 Force on Electrons in a Magnetic Field/5H3001.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3001 Force on Electrons in a Magnetic Field/5H3001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h3001_figure_0.png
+
.
```
@@ -36,13 +35,12 @@ name: 5h3001/figure_0.png
Switch on the oscilloscope and set its time-base so a stable horizontal line appears on the screen (see Diagram). Explain to the students that a beam of electrons is moving from the back to the front side (fluorescent screen) of the oscilloscope, where it appears as a line.
### 1.
-Ask the students what will happen to that line when you approach the oscilloscope tube with a North pole coming from the left side of the oscilloscope. As a comment to their answers, show that the end of the line goes downward (see {numref}`Figure {number} <5h3001/figure_1.png>`B).
+Ask the students what will happen to that line when you approach the oscilloscope tube with a North pole coming from the left side of the oscilloscope. As a comment to their answers, show that the end of the line goes downward (see {numref}`Figure {number} <5h3001_figure_1.png>`B).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h3001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h3001/figure_1.png
----
.
```
Lorentz force and right hand rule can be discussed properly now. As an illustration approach the side of the oscilloscope also with the South pole and see the effect.
@@ -50,46 +48,42 @@ Lorentz force and right hand rule can be discussed properly now. As an illustrat
### 2.
Next step is to approach the front of the oscilloscope with the North pole of the bar magnet. Ask the students what will happen to the horizontal line.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h3001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h3001_figure_2.png
+
.
```
-Then approach the front of the oscilloscope screen with the bar magnet. {numref}`Figure {number} <5h3001/figure_2.png>`B shows the effect on that line. Observe that in het centre of the bar magnet there is no displacement. A more detailed discussion with the students is needed to explain what is happening on the right and left (see Explanation).
+Then approach the front of the oscilloscope screen with the bar magnet. {numref}`Figure {number} <5h3001_figure_2.png>`B shows the effect on that line. Observe that in het centre of the bar magnet there is no displacement. A more detailed discussion with the students is needed to explain what is happening on the right and left (see Explanation).
### 3.
-The next challenging question is: “What will happen to the horizontal line when I approach it with the bar magnet parallel to that line?” After their answers do the demonstration (see {numref}`Figure {number} <5h3001/figure_3.png>`B).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5h3001/figure_3.png
----
+The next challenging question is: “What will happen to the horizontal line when I approach it with the bar magnet parallel to that line?” After their answers do the demonstration (see {numref}`Figure {number} <5h3001_figure_3.png>`B).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5h3001_figure_3.png
+
.
```
Observe that above the magnet the line has risen above the original horizontal line, and at the left and right of the bar magnet that the line has descended below the original horizontal line.
### 4.
-The oscilloscope is connected to the two signal generators and used as an $x-y$ scope (see {numref}`Figure {number} <5h3001/figure_4.png>`B).
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 5h3001/figure_4.png
----
+The oscilloscope is connected to the two signal generators and used as an $x-y$ scope (see {numref}`Figure {number} <5h3001_figure_4.png>`B).
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 5h3001_figure_4.png
+
.
```
The two signal generators are set such that a filled square appears on the screen ( $\mathrm{a}$ Lissajous figure with a random ratio between the two frequencies).
-Slowly approaching this square with a North pole makes visible that the electron beam spirals around the magnetic field lines (see {numref}`Figure {number} <5h3001/figure_5.png>`B), and that the beam even makes
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 5h3001/figure_5.png
----
+Slowly approaching this square with a North pole makes visible that the electron beam spirals around the magnetic field lines (see {numref}`Figure {number} <5h3001_figure_5.png>`B), and that the beam even makes
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 5h3001_figure_5.png
+
.
```
-a focus ({numref}`Figure {number} <5h3001/figure_5.png>`BF and G$ ): the magnetic field can act on a beam of electrons in a way like an optical lens acts on light beams: the magnetic field acts as a lens on the electron-beam.
+a focus ({numref}`Figure {number} <5h3001_figure_5.png>`BF and G$ ): the magnetic field can act on a beam of electrons in a way like an optical lens acts on light beams: the magnetic field acts as a lens on the electron-beam.
## Explanation
@@ -100,21 +94,20 @@ The force ( $F$ ) on a moving ( $v$ ) charge $(\mathrm{q})$ in a magnetic field
### 2. and 3.
-Considering the direction of the force in the {numref}`Figure {number} <5h3001/figure_2.png>`B and {numref}`Figure {number} <5h3001/figure_3.png>`B, again keep in mind that charge $q$ is negative! Key to the force in these drawings is that the angle between $v$ and $B$ is not $0^{\circ}$ (see {numref}`Figure {number} <5h3001/figure_6.png>`B).
+Considering the direction of the force in the {numref}`Figure {number} <5h3001_figure_2.png>`B and {numref}`Figure {number} <5h3001_figure_3.png>`B, again keep in mind that charge $q$ is negative! Key to the force in these drawings is that the angle between $v$ and $B$ is not $0^{\circ}$ (see {numref}`Figure {number} <5h3001_figure_6.png>`B).
+
+```{figure} figures/figure_6.png
+:width: 70%
+:label: 5h3001_figure_6.png
-```{figure} figures/figure_6.png
----
-width: 70%
-name: 5h3001/figure_6.png
----
.
```
-In {numref}`Figure {number} <5h3001/figure_2.png>`B it can be observed also that the central electrons are not deflected. This is right, because for these electrons (and only for these electrons) $\stackrel{\rightharpoonup}{V} \times \vec{B}=0$.
+In {numref}`Figure {number} <5h3001_figure_2.png>`B it can be observed also that the central electrons are not deflected. This is right, because for these electrons (and only for these electrons) $\stackrel{\rightharpoonup}{V} \times \vec{B}=0$.
### 4.
-Figure $5 \mathrm{~B}$ and $5 \mathrm{C}$ show clearly a rotation to the right. This is the same rotation that is already observed in the demonstration of {numref}`Figure {number} <5h3001/figure_2.png>`B: there it was only a line; now the whole square (electron beam) can be seen rotating. (During the whole demonstration the rotations remains clearly visible.) The rotation becomes a spiral, because close to the magnet the magnetic field is so much stronger than farther away from the magnet. (Many books show these spirals, e.g. Giancoli, pag. 694; see SourcesXX.) That focussing occurs illustrates that with electron beams we can create a microscope (electron microscope).
+Figure $5 \mathrm{~B}$ and $5 \mathrm{C}$ show clearly a rotation to the right. This is the same rotation that is already observed in the demonstration of {numref}`Figure {number} <5h3001_figure_2.png>`B: there it was only a line; now the whole square (electron beam) can be seen rotating. (During the whole demonstration the rotations remains clearly visible.) The rotation becomes a spiral, because close to the magnet the magnetic field is so much stronger than farther away from the magnet. (Many books show these spirals, e.g. Giancoli, pag. 694; see SourcesXX.) That focussing occurs illustrates that with electron beams we can create a microscope (electron microscope).
## Remarks
- Also the picture on a TV- or monitor screen can be distorted by using magnets, but take care, the distortion might be irreparable!
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3002 Force on Electrons in a Magnetic Field/5H3002.md b/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3002 Force on Electrons in a Magnetic Field/5H3002.md
index da9e7d4e..eece7b3d 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3002 Force on Electrons in a Magnetic Field/5H3002.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H30 Force on Moving Charges/5H3002 Force on Electrons in a Magnetic Field/5H3002.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h3002_figure_0.png
+
.
```
@@ -39,29 +38,27 @@ Repeat this demonstration but now approaching the beam with a S-pole. Again a sp
## Explanation
The force (F) on a moving (v) electron (charge $e^{-}$) in a magnetic field $(B)$ is expressed as $F=-e \vec{v} \times \vec{B}$. The force is always perpendicular to $\vec{v}$. So, a magnetic field only changes the direction of $\vec{v}$, not its magnitude. The drawings in the Figures explain the trajectories of the electrons in our demonstrations.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h3002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h3002_figure_1.png
+
.
```
-In {numref}`Figure {number} <5h3002/figure_1.png>`A the force $(\mathrm{F})$ is pointing into the picture and so the electron beam is curving away from us (the camera sees the beam turning to the left). While curving away from us, the electron approaches the S-pole: the force on the electron will now point inward, making that, while the electron curves away from us, it also turns to the left (see {numref}`Figure {number} <5h3002/figure_1.png>`B). The more it approaches the S-pole, the more the trajectory will become circular. Summarizing: the path of the approaching electron will be a spiral.. The magnetic field lines act as a trap to the approaching electron. The higher the speed, the deeper it will spiral into the trap. Also when the electron approaches initially closer to the $z$-axis, it will go deeper into the trap, because close to the $z$-axis $B$ and $v$ are almost parallel, making F almost zero.
+In {numref}`Figure {number} <5h3002_figure_1.png>`A the force $(\mathrm{F})$ is pointing into the picture and so the electron beam is curving away from us (the camera sees the beam turning to the left). While curving away from us, the electron approaches the S-pole: the force on the electron will now point inward, making that, while the electron curves away from us, it also turns to the left (see {numref}`Figure {number} <5h3002_figure_1.png>`B). The more it approaches the S-pole, the more the trajectory will become circular. Summarizing: the path of the approaching electron will be a spiral.. The magnetic field lines act as a trap to the approaching electron. The higher the speed, the deeper it will spiral into the trap. Also when the electron approaches initially closer to the $z$-axis, it will go deeper into the trap, because close to the $z$-axis $B$ and $v$ are almost parallel, making F almost zero.
Due to the diverging field, the force $F$ remains pointing downward and finally the electron will spiral away from the S-pole again.
-Positioning a second pole on the other side of the tube makes it possible to have a similar trap on the other side. When we use an opposite pole on the other side, the electrons cannot escape from the region between these poles (see in {numref}`Figure {number} <5h3002/figure_2.png>`A the direction of $F$). The electrons experience at all points a force towards the centre between the poles.
+Positioning a second pole on the other side of the tube makes it possible to have a similar trap on the other side. When we use an opposite pole on the other side, the electrons cannot escape from the region between these poles (see in {numref}`Figure {number} <5h3002_figure_2.png>`A the direction of $F$). The electrons experience at all points a force towards the centre between the poles.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h3002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h3002/figure_2.png
----
.
```
The vertical component of this force makes the electrons oscillate from one pole to the other continuously (the horizontal component causes the circular movement in the spiralled path).
-When the second magnetic pole should be a same magnetic pole (S-pole in this Explanation), the electrons escape from the region between the poles (see in {numref}`Figure {number} <5h3002/figure_2.png>`B the different directions of F).
+When the second magnetic pole should be a same magnetic pole (S-pole in this Explanation), the electrons escape from the region between the poles (see in {numref}`Figure {number} <5h3002_figure_2.png>`B the different directions of F).
## Remarks
- When, in the beginning of the demonstration, the $\mathrm{N}$-pole is replaced by a $\mathrm{S}$-pole the trap also functions. The electron beam spirals into the other direction when a different pole is used. Due to the configuration of our electron tube it is not possible to show a satisfactory trapping when approaching the electron beam head on by a S-pole.
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4001 Force Effect of Current/5H4001.md b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4001 Force Effect of Current/5H4001.md
index 763359d2..055cdb43 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4001 Force Effect of Current/5H4001.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4001 Force Effect of Current/5H4001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h4001_figure_0.png
+
.
```
@@ -27,20 +26,18 @@ name: 5h4001/figure_0.png
- Power supply, $100\mathrm{~A}$.
## Presentation
-First connect the $2 \mathrm{~m}$-wire to the 100A powersupply. Position the wire-parts close together (see {numref}`Figure {number} <5h4001/figure_1.png>`A). Switch on the powersupply and see how the wire-parts move away from each other.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h4001/figure_1.png
----
+First connect the $2 \mathrm{~m}$-wire to the 100A powersupply. Position the wire-parts close together (see {numref}`Figure {number} <5h4001_figure_1.png>`A). Switch on the powersupply and see how the wire-parts move away from each other.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h4001_figure_1.png
+
.
```
-To make this effect stronger, we use the demonstration as shown in Diagram and {numref}`Figure {number} <5h4001/figure_2.png>`A. First the capacitor is charged to $500 \mathrm{~V}$. Then switch $\mathrm{S}_{1}$ is opened and the high current switch is closed. The wire-parts fly away from each other ({numref}`Figure {number} <5h4001/figure_2.png>`B).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h4001/figure_2.png
----
+To make this effect stronger, we use the demonstration as shown in Diagram and {numref}`Figure {number} <5h4001_figure_2.png>`A. First the capacitor is charged to $500 \mathrm{~V}$. Then switch $\mathrm{S}_{1}$ is opened and the high current switch is closed. The wire-parts fly away from each other ({numref}`Figure {number} <5h4001_figure_2.png>`B).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h4001_figure_2.png
+
.
```
@@ -51,7 +48,7 @@ The first part of the demonstration shows that opposing currents exert a repelli
On this force effect the definition of the Ampere as the unit of electric current is based $\frac{\Delta F}{\Delta l}=2 \times 10^{-7} \frac{I_{1} I_{2}}{r}$. This demonstration, using $\mathrm{I}_{1}=\mathrm{I}_{2}=100 \mathrm{~A}$ and $\Delta l=1 \mathrm{~m}$ has to deal with a force of only $2 \cdot 10^{-3} \mathrm{~N}$. No wonder the displacement of the wire is small.
-In the second part of the demonstration the current is much higher. Supposing the wire and contacts having a resistance of $0.5 \Omega$, a current of $1000 \mathrm{~A}$ is flowing in the beginning of the discharge. Then the force on the wireloop is . $2 \mathrm{~N}$. This hundredfold higher force exists only a short time. Not only F diminishes due to the increasing distance, but also due to the reducing discharge current (the circuit has a RC-time of about $1 \mathrm{msec}$ ). Due to its impulse the wire-parts continue to move after the discharge ({numref}`Figure {number} <5h4001/figure_2.png>`B).
+In the second part of the demonstration the current is much higher. Supposing the wire and contacts having a resistance of $0.5 \Omega$, a current of $1000 \mathrm{~A}$ is flowing in the beginning of the discharge. Then the force on the wireloop is . $2 \mathrm{~N}$. This hundredfold higher force exists only a short time. Not only F diminishes due to the increasing distance, but also due to the reducing discharge current (the circuit has a RC-time of about $1 \mathrm{msec}$ ). Due to its impulse the wire-parts continue to move after the discharge ({numref}`Figure {number} <5h4001_figure_2.png>`B).
If current should flow continuously the wire would take the shape of a perfect circle.
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4002 Lorentz Force/5H4002.md b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4002 Lorentz Force/5H4002.md
index 4d16edf8..349c14f5 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4002 Lorentz Force/5H4002.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4002 Lorentz Force/5H4002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h4002_figure_0.png
+
.
```
@@ -24,14 +23,13 @@ name: 5h4002/figure_0.png
## Presentation
The lamp is connected to the mains and the filament is glowing. The filament can be seen clearly.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h4002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h4002_figure_1.png
+
.
```
-The bar magnet approaches the lamp and the individual turns of the spiral filament show themselves as broadened bands (see {numref}`Figure {number} <5h4002/figure_1.png>`). The filament performs a fast reciprocating motion
+The bar magnet approaches the lamp and the individual turns of the spiral filament show themselves as broadened bands (see {numref}`Figure {number} <5h4002_figure_1.png>`). The filament performs a fast reciprocating motion
## Explanation
The reciprocating motion of the filament indicates that a force is acting and that it is acting to and fro."To and fro" is caused by the constantly changing direction of the current ( $50 \mathrm{~Hz}$ ).
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/5H4003.md b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/5H4003.md
index 424e72b0..5e4b4660 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/5H4003.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/5H4003.md
@@ -10,11 +10,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h4003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h4003_figure_0.png
+
.
```
@@ -39,13 +38,12 @@ Applying Biot-Savart's law it can be shown that the force on a current element $
## Remarks
- Verifying $F \propto I$ supposes that only the displacement of the wire between the magnetic poles is considered. Only in this region the magnetic field is uniform and $\vec{B}$ can be considered constant.
-- The demonstration can also be used to estimate the value of the fluxdensity B. In $F=I / B_{f}$ $I$ and /are known (see {numref}`Figure {number} <5h4003/figure_1.png>`).
+- The demonstration can also be used to estimate the value of the fluxdensity B. In $F=I / B_{f}$ $I$ and /are known (see {numref}`Figure {number} <5h4003_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h4003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h4003/figure_1.png
----
.
```
$I$ is given such a value that it deflects the full width of the gap between the poles $(2 \mathrm{~cm})$. (In our case the current needed for that is .5A.) The force needed for such a deflection can be estimated when we know the mass of the suspended wire. (In our case: $\mathrm{m}=.032 \mathrm{~kg}$, so $\mathrm{F}=(1 / 40) \cdot(.032) \cdot(10)=8 \mathrm{mN}$. Then $B$ will be $.3(2) \mathrm{T})$.
@@ -54,7 +52,6 @@ $I$ is given such a value that it deflects the full width of the gap between the
```{iframe} https://www.youtube.com/watch?v=CvBMtKML0S8
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/qr_images/qrcode_watch_v_CvBMtKML0S8.svg b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/qr_images/qrcode_watch_v_CvBMtKML0S8.svg
new file mode 100644
index 00000000..6e15f667
--- /dev/null
+++ b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4003 Lorentz Force/qr_images/qrcode_watch_v_CvBMtKML0S8.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4004 Parallel Wires/5H4004.md b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4004 Parallel Wires/5H4004.md
index fc25d0c7..f353e657 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4004 Parallel Wires/5H4004.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H40 Force on Current Wires/5H4004 Parallel Wires/5H4004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h4004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h4004_figure_0.png
+
.
```
@@ -24,32 +23,30 @@ name: 5h4004/figure_0.png
## Presentation
-The two long wires are suspended from one clamp, close to the rigid white screen. One of the wires is also clamped at the lower end of the white screen and stretched. The second wire is hanging freely in such a way that at the lower end it is about $2 \mathrm{~cm}$ seperated from the fixed wire (see Diagram and {numref}`Figure {number} <5h4004/figure_1.png>`A).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h4004/figure_1.png
----
+The two long wires are suspended from one clamp, close to the rigid white screen. One of the wires is also clamped at the lower end of the white screen and stretched. The second wire is hanging freely in such a way that at the lower end it is about $2 \mathrm{~cm}$ seperated from the fixed wire (see Diagram and {numref}`Figure {number} <5h4004_figure_1.png>`A).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h4004_figure_1.png
+
.
```
Parallel wires
-The wiring is set up in such a way that both wires conduct the current in the same direction ({numref}`Figure {number} <5h4004/figure_1.png>`A). When switching on the current we see that the "loose" wire moves closer to the fixed wire.
+The wiring is set up in such a way that both wires conduct the current in the same direction ({numref}`Figure {number} <5h4004_figure_1.png>`A). When switching on the current we see that the "loose" wire moves closer to the fixed wire.
-Then the wiring is changed so that the two wires conduct the current in opposite directions ({numref}`Figure {number} <5h4004/figure_1.png>`B). Switching on the current now shows that the "loose" wire is moving away from the fixed wire.
+Then the wiring is changed so that the two wires conduct the current in opposite directions ({numref}`Figure {number} <5h4004_figure_1.png>`B). Switching on the current now shows that the "loose" wire is moving away from the fixed wire.
## Explanation
The magnetic induction around a current-carrying wire equals: $B(r)=\frac{\mu_{0} I_{1}}{2 \pi r}$ and is directed circularly around that wire (corkscrew). The force on a current in a magnetic field equals $F=I_{2} l B(r)$ and is directed perpendicular to $I_{2}$ and $B . v_{0}$ being $4 \pi .10^{-7} \mathrm{Hm}^{-}$
${ }^{1}$ leads to $F=2.10^{-7} \frac{I_{1} I_{2} l}{r}$.
-Applying the rigth-hand rule shows the direction of this force between current $I_{1}(B)$ and $I_{2}$ (see {numref}`Figure {number} <5h4004/figure_2.png>`).
+Applying the rigth-hand rule shows the direction of this force between current $I_{1}(B)$ and $I_{2}$ (see {numref}`Figure {number} <5h4004_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h4004_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h4004/figure_2.png
----
.
```
Calculating $\mathrm{F}$ for every $1 \mathrm{~cm}$ length of wire we find:
diff --git a/book/book/5 EM/5H magnetic fields and forces/5H50 Torques on Coils/5H5001 Current Loop in Magnetic Field/5H5001.md b/book/book/5 EM/5H magnetic fields and forces/5H50 Torques on Coils/5H5001 Current Loop in Magnetic Field/5H5001.md
index 3ab94af0..bb9a3627 100644
--- a/book/book/5 EM/5H magnetic fields and forces/5H50 Torques on Coils/5H5001 Current Loop in Magnetic Field/5H5001.md
+++ b/book/book/5 EM/5H magnetic fields and forces/5H50 Torques on Coils/5H5001 Current Loop in Magnetic Field/5H5001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5h5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5h5001_figure_0.png
+
.
```
@@ -39,40 +38,36 @@ name: 5h5001/figure_0.png
## Presentation
- Using the array of compass needles we show that there is a uniform magnetic field between the permanent magnets (see {numref}`Figure {number} <5h5001/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5h5001/figure_1.png
----
+ Using the array of compass needles we show that there is a uniform magnetic field between the permanent magnets (see {numref}`Figure {number} <5h5001_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5h5001_figure_1.png
+
.
```
-Close to the magnets the field is strongly divergent/convergent (see {numref}`Figure {number} <5h5001/figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5h5001/figure_2.png
----
+Close to the magnets the field is strongly divergent/convergent (see {numref}`Figure {number} <5h5001_figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5h5001_figure_2.png
+
.
```
-Then the coil is suspended between the two magnets (see Diagram). Connecting the power supply to the coil shows that the coil makes a rotation and lines up with the magnetic field (see {numref}`Figure {number} <5h5001/figure_3.png>`). There it remains at rest.
+Then the coil is suspended between the two magnets (see Diagram). Connecting the power supply to the coil shows that the coil makes a rotation and lines up with the magnetic field (see {numref}`Figure {number} <5h5001_figure_3.png>`). There it remains at rest.
Conclusion is that in a homogeneous magnetic field a current carrying coil (a dipole) experiences a torque that lines up that dipole with the field. And in that uniform field there is no net force.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5h5001/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5h5001_figure_3.png
+
.
```
-Then the coil is displaced a little from its central position: It attracts itself towards one of the magnets and sticks there (see {numref}`Figure {number} <5h5001/figure_4.png>`).
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 5h5001/figure_4.png
----
+Then the coil is displaced a little from its central position: It attracts itself towards one of the magnets and sticks there (see {numref}`Figure {number} <5h5001_figure_4.png>`).
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 5h5001_figure_4.png
+
.
```
Conclusion is that in a non-uniform field there is a net force on a current loop (dipole).
@@ -80,12 +75,11 @@ Conclusion is that in a non-uniform field there is a net force on a current loop
## Explanation
There are Lorentz-forces on all sides of the coil. The forces on the bottom- and topside of the coil cancel (they only tend to stretch the coil). The two forces on the sides are also equal and opposite but they do generate a torque $\vec{N} . \vec{N}=\vec{m} \times \vec{B}$ ( $\vec{B}$ is the magnetic field and $\vec{A}, \vec{A}$ being the area of the current loop).
-When the field is non-uniform, there is a radial component of $\mathrm{B}$ and there will be a net force towards the magnet (see {numref}`Figure {number} <5h5001/figure_5.png>`).
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 5h5001/figure_5.png
----
+When the field is non-uniform, there is a radial component of $\mathrm{B}$ and there will be a net force towards the magnet (see {numref}`Figure {number} <5h5001_figure_5.png>`).
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 5h5001_figure_5.png
+
.
```
diff --git a/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/5J1001.md b/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/5J1001.md
index 48729262..838ced3c 100644
--- a/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/5J1001.md
+++ b/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/5J1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5j1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5j1001_figure_0.png
+
.
```
@@ -23,7 +22,7 @@ name: 5j1001/figure_0.png
- U-core with bar.
- 2 Demonstration meters.
- Safety connection box .
-- Measuring junction box (See {numref}`Figure {number} <5j1001/figure_4.png>`).
+- Measuring junction box (See {numref}`Figure {number} <5j1001_figure_4.png>`).
- Net-adapter for mobile telephone (or other appliance).
## Safety
@@ -32,27 +31,25 @@ name: 5j1001/figure_0.png
## Presentation
-The circuit is build as shown in {numref}`Figure {number} <5j1001/figure_1.png>` and in Diagram. First we show the circuit setup to the students and then connect the two Voltmeters.
+The circuit is build as shown in {numref}`Figure {number} <5j1001_figure_1.png>` and in Diagram. First we show the circuit setup to the students and then connect the two Voltmeters.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5j1001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5j1001_figure_1.png
+
.
```
-1. Connecting the $220 \mathrm{~V}$ to the circuit makes the lamp glows strongly (see {numref}`Figure {number} <5j1001/figure_2.png>`A ). The Voltmeter connected to the lamp reads almost $220 \mathrm{~V}$ : All voltage appears across the lamp; just a very little voltage is read across the coil.
+1. Connecting the $220 \mathrm{~V}$ to the circuit makes the lamp glows strongly (see {numref}`Figure {number} <5j1001_figure_2.png>`A ). The Voltmeter connected to the lamp reads almost $220 \mathrm{~V}$ : All voltage appears across the lamp; just a very little voltage is read across the coil.
***Conclusion*** is that only a very small emf of self-inductance is generated in the coil.
2. The bar is partly shifted on to the U-core. As soon as the bar touches the second leg of the $U$-core the lamp dims (see figure $2 B$ ). the Voltmeter across the lamp shows a lower voltage now and at the same time we observe an increase in voltage across the coil.
***Conclusion*** is that there is now a higher emf of self-inductance that opposes the $220 \mathrm{~V}$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5j1001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5j1001_figure_2.png
+
.
```
@@ -62,22 +59,20 @@ name: 5j1001/figure_2.png
Shifting the bar back and forth across the U-core makes the lamp dim less or more.
-4. Finally we disconnect the lamp. Now only the self-inductance is connected to the $220 \mathrm{~V}$ (see {numref}`Figure {number} <5j1001/figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5j1001/figure_3.png
----
+4. Finally we disconnect the lamp. Now only the self-inductance is connected to the $220 \mathrm{~V}$ (see {numref}`Figure {number} <5j1001_figure_3.png>`).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5j1001_figure_3.png
+
.
```
Now the effect of self-inductance is most clear: the voltmeter reads $220 \mathrm{~V}$ across the coil, and only a small current is flowing (we measure $0.4 \mathrm{~A}$ ). When there would be no self-inductance, the current would be $220 \mathrm{~V} / 2.5 \Omega=88 \mathrm{~A}$ !
-Conclusion is that the emf of self-inductance really opposes the applied voltage. 5. The same demonstration is performed with a commercial net-adapter (used as charger for a mobile telephone; see {numref}`Figure {number} <5j1001/figure_4.png>`). Here also only the primary coil of the adapter is connected to the mains. We read a current of only $0.3 \mathrm{~mA}$!
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 5j1001/figure_4.png
----
+Conclusion is that the emf of self-inductance really opposes the applied voltage. 5. The same demonstration is performed with a commercial net-adapter (used as charger for a mobile telephone; see {numref}`Figure {number} <5j1001_figure_4.png>`). Here also only the primary coil of the adapter is connected to the mains. We read a current of only $0.3 \mathrm{~mA}$!
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 5j1001_figure_4.png
+
.
```
@@ -89,21 +84,20 @@ $L=\frac{\mu_{r} \mu_{0} N^{2} A}{l} L=\frac{\mu_{r} \mu_{0} N^{2} A}{l}$. This
## Remarks
- The core on the bar makes a lot of noise. This is a $100 \mathrm{~Hz}$ mains hum due to the mains frequency $(50 \mathrm{~Hz})$.
- The effect of self-inductance can also be translated into impedance of the circuit. In our demonstration 4. the circuit shows an impedance of $220 \mathrm{~V} / 0.4 \mathrm{~A}=550 \Omega$ instead of the $2.5 \Omega$ of the copper coil.
-- In figure B we read $V_{\text {coil }}=130 \mathrm{~V}$ and $V_{\text {lamp }}=110 \mathrm{~V}$. Students easily read this as a total of $240 \mathrm{~V}$, so higher than the applied $220 \mathrm{~V}$. Phase-shift between these two voltages is responsible for that. The situation must be something like {numref}`Figure {number} <5j1001/figure_5.png>` below shows.
+- In figure B we read $V_{\text {coil }}=130 \mathrm{~V}$ and $V_{\text {lamp }}=110 \mathrm{~V}$. Students easily read this as a total of $240 \mathrm{~V}$, so higher than the applied $220 \mathrm{~V}$. Phase-shift between these two voltages is responsible for that. The situation must be something like {numref}`Figure {number} <5j1001_figure_5.png>` below shows.
+
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 5j1001_figure_5.png
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 5j1001/figure_5.png
----
.
```
## Video Rhett Allain
```{iframe} https://www.youtube.com/watch?v=J2epiOv40Oo
:width: 70%
-:height: 400px
:align: center
+
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
```
diff --git a/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg b/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg
new file mode 100644
index 00000000..457ae17a
--- /dev/null
+++ b/book/book/5 EM/5J inductance/5J10 Self Inductance/5J1001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1001 Damped Galvanometer/5K1001.md b/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1001 Damped Galvanometer/5K1001.md
index 9ef35a2e..1b4e0677 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1001 Damped Galvanometer/5K1001.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1001 Damped Galvanometer/5K1001.md
@@ -8,11 +8,10 @@
* 3A50 (Damped Oscillators) 5K10 (Induced Currents and Forces)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k1001_figure_0.png
+
.
```
@@ -22,16 +21,15 @@ name: 5k1001/figure_0.png
* Resistance-box ($10\mathrm{~k\Omega}$)
* Laser
* Stopwatch
- * (Torsionwire model, see {numref}`Figure {number} <5k1001/figure_2.png>`).
+ * (Torsionwire model, see {numref}`Figure {number} <5k1001_figure_2.png>`).
## Presentation
-Galvanometer and laser are positioned in such a way that, in the neutral position of the galvanometer, the reflected laser beam is projected on the blackboard behind the laser (see {numref}`Figure {number} <5k1001/figure_1.png>`). This neutral position is chalk-marked on the blackboard.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k1001/figure_1.png
----
+Galvanometer and laser are positioned in such a way that, in the neutral position of the galvanometer, the reflected laser beam is projected on the blackboard behind the laser (see {numref}`Figure {number} <5k1001_figure_1.png>`). This neutral position is chalk-marked on the blackboard.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k1001_figure_1.png
+
.
```
@@ -79,13 +77,12 @@ Critical damping when $r^{2}=4 I \kappa$. Then equilibrium is reached in the sho
$\omega^{2}=\frac{\kappa}{I}-\left(\frac{r}{2 I}\right)^{2}$ shows that $\omega$ has a lower value than in the undamped situation. $\omega$
## Remarks
-- When the students have not seen a torsionwire system before, such a system is shortly explained to them using a large scale model (a piece of rope, having a rectangular sheet of metal and a small coil, taped to it. See {numref}`Figure {number} <5k1001/figure_2.png>`.)
+- When the students have not seen a torsionwire system before, such a system is shortly explained to them using a large scale model (a piece of rope, having a rectangular sheet of metal and a small coil, taped to it. See {numref}`Figure {number} <5k1001_figure_2.png>`.)
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5k1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5k1001/figure_2.png
----
.
```
diff --git a/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1002 Skipping Rope/5K1002.md b/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1002 Skipping Rope/5K1002.md
index 8529e6c8..9f4f2696 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1002 Skipping Rope/5K1002.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K10 Induced Currents and Forces/5K1002 Skipping Rope/5K1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k1002_figure_0.png
+
.
```
@@ -30,30 +29,28 @@ name: 5k1002/figure_0.png
## Presentation
The compass needle is placed on the overheadprojector to indicate the North-South direction in the lecturehall.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k1002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k1002_figure_1.png
+
.
```
-The demonstration is set up as shown in Diagram, and positioned so that the axis of rotation of the skipping rope is perpendicular to the indicated $\mathrm{N}$-S direction (see Diagram A). The skipping rope is connected to the operational amplifier circuit (see {numref}`Figure {number} <5k1002/figure_1.png>`A). The output of the amplifier is connected to the oscilloscope, having a slowly moving time-base (.1sec/DIV).
+The demonstration is set up as shown in Diagram, and positioned so that the axis of rotation of the skipping rope is perpendicular to the indicated $\mathrm{N}$-S direction (see Diagram A). The skipping rope is connected to the operational amplifier circuit (see {numref}`Figure {number} <5k1002_figure_1.png>`A). The output of the amplifier is connected to the oscilloscope, having a slowly moving time-base (.1sec/DIV).
The skipping rope is set in rotation (see Diagram C) and the moving spot on the oscilloscope screen is seen to move up and down, showing positive - and negative induced voltages. When the skipping rope is speeded up the amplitude of the induced voltage increases.
-In order to observe the induced voltage more in detail, the output is also connected to the interface of the data-acquisition system. A voltage-time graph is displayed to the students and they observe the registration of the (1000 times amplified) induced voltage while the skipping rope is making about 15 full turns, some slow, some fast (see {numref}`Figure {number} <5k1002/figure_2.png>`). Clearly the sinusoidal shape of the induced voltage can be observed.
+In order to observe the induced voltage more in detail, the output is also connected to the interface of the data-acquisition system. A voltage-time graph is displayed to the students and they observe the registration of the (1000 times amplified) induced voltage while the skipping rope is making about 15 full turns, some slow, some fast (see {numref}`Figure {number} <5k1002_figure_2.png>`). Clearly the sinusoidal shape of the induced voltage can be observed.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5k1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5k1002/figure_2.png
----
.
```
-Finally, a part of the graph with a full cycle is selected and by means of the graph features in the statistics software the integration of a selected one half of a sine is determined (see {numref}`Figure {number} <5k1002/figure_2.png>`B). We read $0.155 \mathrm{~V}$. Applying Faraday's induction law and estimating the area of the skipping rope (use the overheadsheet), we find for the Earth's magnetic field $B_{0}=28 U T$ (see Explanation). This is good enough (good enough for a demonstration) when compared with values given in literature.
+Finally, a part of the graph with a full cycle is selected and by means of the graph features in the statistics software the integration of a selected one half of a sine is determined (see {numref}`Figure {number} <5k1002_figure_2.png>`B). We read $0.155 \mathrm{~V}$. Applying Faraday's induction law and estimating the area of the skipping rope (use the overheadsheet), we find for the Earth's magnetic field $B_{0}=28 U T$ (see Explanation). This is good enough (good enough for a demonstration) when compared with values given in literature.
## Explanation
-The induced voltage ( $E$ ) is given by Faraday's induction law as $E(t)=B_{0} \frac{d A}{d t} . B_{0}$ is the magnetic flux density; $A$ is the area spanned by the skipping rope and its rotational axis. The plane of the skipping rope changes as $A=A_{0} \cos \omega t$ (see {numref}`Figure {number} <5k1002/figure_1.png>`C), so $\frac{d A}{d t}=-A_{0} \sin \omega t$, and $E(t)=B_{0} A_{0} \omega$ sin $\omega t$ : the induced voltage $(E)$ changes sinusoidally as the registered graph shows convincingly.
+The induced voltage ( $E$ ) is given by Faraday's induction law as $E(t)=B_{0} \frac{d A}{d t} . B_{0}$ is the magnetic flux density; $A$ is the area spanned by the skipping rope and its rotational axis. The plane of the skipping rope changes as $A=A_{0} \cos \omega t$ (see {numref}`Figure {number} <5k1002_figure_1.png>`C), so $\frac{d A}{d t}=-A_{0} \sin \omega t$, and $E(t)=B_{0} A_{0} \omega$ sin $\omega t$ : the induced voltage $(E)$ changes sinusoidally as the registered graph shows convincingly.
An interesting quantity is $\int E(t) d t$ (voltage surge, or voltage impulse, in units [Vs]). We will use this quantity to determine the Earth's magnetic field.
@@ -61,14 +58,14 @@ From Faraday's induction law: $E(t) d t=-B_{0} d A$ and $\frac{d A}{d t}=-A_{0}
$\int E(t) d t=-B_{0} A_{0} \omega \int \sin \omega t d t$. When we look at one half of a full cycle, we have:
-$\int E(t) d t=-B_{0} A_{0} \cos (\omega t)_{0}^{\pi}=2 B_{0} A_{0}$. From {numref}`Figure {number} <5k1002/figure_2.png>`B we read $\int E(t) d t$ equals
+$\int E(t) d t=-B_{0} A_{0} \cos (\omega t)_{0}^{\pi}=2 B_{0} A_{0}$. From {numref}`Figure {number} <5k1002_figure_2.png>`B we read $\int E(t) d t$ equals
-$0,155 \mathrm{~V}$. {numref}`Figure {number} <5k1002/figure_1.png>`B is used to estimate the area $A_{o}$ of the catenary of the suspended skipping rope. With the dimensions given, we estimate a little less than $3 \mathrm{~m}^{2}$, so let us say $2.8 \mathrm{~m}^{2}$. With these numbers we find for the Earth's magnetic field: $B_{0}=28 U T$.
+$0,155 \mathrm{~V}$. {numref}`Figure {number} <5k1002_figure_1.png>`B is used to estimate the area $A_{o}$ of the catenary of the suspended skipping rope. With the dimensions given, we estimate a little less than $3 \mathrm{~m}^{2}$, so let us say $2.8 \mathrm{~m}^{2}$. With these numbers we find for the Earth's magnetic field: $B_{0}=28 U T$.
## Remarks
- In the operational amplifier circuit the $100 \mathrm{nF}$ capacitor is needed to reduce the noise of the mains. The $2,2 \mathrm{uF}$ capacitor is applied to block the dc-offset that is usually present at the output of such amplifiers.
- The table with amplifier and oscilloscope has to stand firmly on the ground (see DiagramB), because rotating the rope gives forceful jerks to that table.
-- The registered induced voltage is not really symmetrical (see {numref}`Figure {number} <5k1002/figure_2.png>`) this is due to the way of turning such a skipping rope: at each cycle you give a kind of jerk when swinging the rope upwards, so in its cycle the angular speed is not really constant.
+- The registered induced voltage is not really symmetrical (see {numref}`Figure {number} <5k1002_figure_2.png>`) this is due to the way of turning such a skipping rope: at each cycle you give a kind of jerk when swinging the rope upwards, so in its cycle the angular speed is not really constant.
- During the first run, when registering the voltage-time graph, we make the statistics software indicate the mean y-value (voltage). In that way it is seen that the first and last not so beautiful movement of the skipping rope has not really a significant influence on our further measurements.
diff --git a/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2001 Aragos Compass Needle/5K2001.md b/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2001 Aragos Compass Needle/5K2001.md
index fb6bc9e4..acee7941 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2001 Aragos Compass Needle/5K2001.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2001 Aragos Compass Needle/5K2001.md
@@ -8,11 +8,10 @@ To show the historic experiment of Arago on eddy currents.
* 5K20 (Eddy Currents)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k2001/figure_0
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k2001_figure_0
+
.
```
@@ -28,25 +27,23 @@ The needle point support is very sharp!
## Presentation
-A top-view image of the compass-needle is presented to the audience (see {numref}`Figure {number} <5k2001/figure_1>`).
+A top-view image of the compass-needle is presented to the audience (see {numref}`Figure {number} <5k2001_figure_1>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k2001/figure_1
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k2001_figure_1
---
.
```
It is standing still, pointing in the magnetic North-South direction. By hand we deflect the needle $90^{\circ}$. Then let it go. The needle swings quite some time before it comes to a rest again. We count around 30 complete swings in total.
-Then the copper sheet is shifted close under the magnetic needle (see Diagram B and {numref}`Figure {number} <5k2001/figure_2>`).
+Then the copper sheet is shifted close under the magnetic needle (see Diagram B and {numref}`Figure {number} <5k2001_figure_2>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5k2001_figure_2
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5k2001/figure_2
----
.
```
@@ -59,15 +56,14 @@ Historically the phenomenon was observed by Arago in 1825. He observed that a co
## Explanation
Faraday’s law explains the slowing down.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5k2001/figure_3
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5k2001_figure_3
+
.
```
-An emf is induced in the copper plate when there is a change in magnetic field. There is a change in magnetic field at position P and Q in {numref}`Figure {number} <5k2001/figure_1>`: In P there is a decrease in magnetic field; in Q an increase. According to Lenz’s law, currents are induced in the copper plate such that they oppose that change in flux. Opposing change in flux means that the needle has to move slower (when the needle stands still there is no change in flux at all). So, at P an eddy-current will flow as to produce a S-pole in the copper plate, that slows down the moving away N-pole of the needle. In the same way an eddy-current will flow at Q in such a way as to produce a N-pole in the copper plate, that slows down the approaching N-pole of the needle.
+An emf is induced in the copper plate when there is a change in magnetic field. There is a change in magnetic field at position P and Q in {numref}`Figure {number} <5k2001_figure_1>`: In P there is a decrease in magnetic field; in Q an increase. According to Lenz’s law, currents are induced in the copper plate such that they oppose that change in flux. Opposing change in flux means that the needle has to move slower (when the needle stands still there is no change in flux at all). So, at P an eddy-current will flow as to produce a S-pole in the copper plate, that slows down the moving away N-pole of the needle. In the same way an eddy-current will flow at Q in such a way as to produce a N-pole in the copper plate, that slows down the approaching N-pole of the needle.
## Remarks
* Counting the number of oscillations of the needle takes some time. Yet, the students, only seeing the needle swinging to and fro, show no signs of impatience. Our experience is that they even become very focussed on the experiment!
diff --git a/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2002 Aragos Disk/5K2002.md b/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2002 Aragos Disk/5K2002.md
index f40e77eb..c473a29b 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2002 Aragos Disk/5K2002.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K20 Eddy Currents/5K2002 Aragos Disk/5K2002.md
@@ -11,11 +11,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k2002_figure_0.png
+
.
```
@@ -42,14 +41,13 @@ Immediately the copper disk starts turning as well, trying to follow the magnets
-When we stop the rotation of the magnets, the copper disk brakes and will stop its movement soon.
## Explanation
-We explain the first presented demonstration (see {numref}`Figure {number} <5k2002/figure_1.png>`). The other two demonstrated situations can be explained similarly.
+We explain the first presented demonstration (see {numref}`Figure {number} <5k2002_figure_1.png>`). The other two demonstrated situations can be explained similarly.
In general, an emf is induced in the copper disk when there is a change in magnetic field. This happens at the front- and backside of the passing magnet. At these points, eddy currents flow in the copper disk.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k2002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k2002_figure_1.png
+
.
```
### Explaining with Lenz's law.
@@ -70,7 +68,7 @@ So, in the disk a current is induced such that it produces a flux opposing that
-When a flux is moving away from the copper disk, the copper disk "wants" to move with it in order to maintain its flux-present situation. So, in the disk a current is induced such that it produces a flux in the same direction as that of the magnet (this happens at tail-side of the moving magnet).
-Looking at the induced currents and the subsequent Lorentz-force (induced current in magnetic filed), both forces on the front- and tail-side make the copper disk move with the magnet (see {numref}`Figure {number} <5k2002/figure_1.png>`), showing the direction of the Lorentz forces ( $F_{L}$ ) making the disk move in the same direction as the magnet does. (Only the forces closest to the magnet are drawn.)
+Looking at the induced currents and the subsequent Lorentz-force (induced current in magnetic filed), both forces on the front- and tail-side make the copper disk move with the magnet (see {numref}`Figure {number} <5k2002_figure_1.png>`), showing the direction of the Lorentz forces ( $F_{L}$ ) making the disk move in the same direction as the magnet does. (Only the forces closest to the magnet are drawn.)
## Remarks
diff --git a/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3001 Electric Power Transmission Line/5K3001.md b/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3001 Electric Power Transmission Line/5K3001.md
index 87877afc..4fcfe1f0 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3001 Electric Power Transmission Line/5K3001.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3001 Electric Power Transmission Line/5K3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k3001_figure_0.png
+
.
```
@@ -26,24 +25,23 @@ name: 5k3001/figure_0.png
- Multi scale voltmeter, large display.
## Presentation
-First it is shown that the $6 \mathrm{~V} / 30 \mathrm{~W}$ glows brightly when connected to the $6 \mathrm{~V}$ power supply. The demonstration is set up as shown in Diagram and {numref}`Figure {number} <5k3001/figure_1.png>`A. Tell the students that in order to simulate a long distance between the power supply and the lamp resistance wire is used between them.
+First it is shown that the $6 \mathrm{~V} / 30 \mathrm{~W}$ glows brightly when connected to the $6 \mathrm{~V}$ power supply. The demonstration is set up as shown in Diagram and {numref}`Figure {number} <5k3001_figure_1.png>`A. Tell the students that in order to simulate a long distance between the power supply and the lamp resistance wire is used between them.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k3001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k3001/figure_1.png
----
.
```
-The power supply is switched on, but the lamp shows no light. Using the voltmeter it is seen that there is no voltage across the lamp. Sliding the leads of the voltmeter along the long wires shows that all the voltage of the power supply is lost in these wires. The two identical transformers are connected into the circuit (see {numref}`Figure {number} <5k3001/figure_1.png>`B). The power supply is switched on and the lamp lights brightly!
+The power supply is switched on, but the lamp shows no light. Using the voltmeter it is seen that there is no voltage across the lamp. Sliding the leads of the voltmeter along the long wires shows that all the voltage of the power supply is lost in these wires. The two identical transformers are connected into the circuit (see {numref}`Figure {number} <5k3001_figure_1.png>`B). The power supply is switched on and the lamp lights brightly!
## Explanation
In the first part of the demonstration almost all power is lost in the long wires, because of the high resistance of these wires compared to the resistance-value of the lamp. In the second part of the demonstration, the first transformer steps the $6 \mathrm{~V}$ up to $200 \mathrm{~V}$ (using the voltmeter this can be checked). To transport power at such a higher voltage a much lower current is needed; the current in the "long" wires is now $500 / 15$ times lower than in part A of the demonstration. Then the power lost in these wires is $(500 / 15)^{2}$ times lower; the power loss in the transport wires is reduced more than a factor 1000!
-To calculate exactly we have to consider {numref}`Figure {number} <5k3001/figure_1.png>`C.
+To calculate exactly we have to consider {numref}`Figure {number} <5k3001_figure_1.png>`C.
The lamp has a resistance of about $1 \Omega$. Since $E_{2}=E_{1}\left(n_{2} / n_{1}\right)$ and $I_{2}=I_{1}\left(n_{1} / n_{2}\right)$, we find $E_{2} / I_{2}=R_{\text {lamp }}\left(n_{2} / n_{1}\right)^{2}$. This results in that $E_{2}$ 'sees' $R_{\text {lamp }}$ as $1111 \Omega$.
-{numref}`Figure {number} <5k3001/figure_1.png>`D explains the rest: The $6 \mathrm{~V}$ of the power supply is transformed by the first transformer to 200 V. Considering the resistance values, $167 \mathrm{~V}$ remains at the second transformer. This second transformer steps this voltage down to $5 \mathrm{~V}$. This is enough to make the lamp glow.
+{numref}`Figure {number} <5k3001_figure_1.png>`D explains the rest: The $6 \mathrm{~V}$ of the power supply is transformed by the first transformer to 200 V. Considering the resistance values, $167 \mathrm{~V}$ remains at the second transformer. This second transformer steps this voltage down to $5 \mathrm{~V}$. This is enough to make the lamp glow.
## Remarks
- Take care with the $200 \mathrm{~V}$ in the second part of the demonstration.
diff --git a/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3002 Transformer/5K3002.md b/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3002 Transformer/5K3002.md
index c0df05c4..3216d69c 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3002 Transformer/5K3002.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K30 Transformers/5K3002 Transformer/5K3002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k3002_figure_0.png
+
.
```
@@ -31,24 +30,22 @@ name: 5k3002/figure_0.png
## Presentation
- The demonstration is set up as shown in Diagram and {numref}`Figure {number} <5k3002/figure_1.png>`.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k3002/figure_1.png
----
+ The demonstration is set up as shown in Diagram and {numref}`Figure {number} <5k3002_figure_1.png>`.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k3002_figure_1.png
+
.
```
The $220 \mathrm{~V}$ is switched on and the students can read on the $\mathrm{V}$-meter that in the loop around the core a voltage of around $.4 \mathrm{~V}$ is induced.
-Then the demonstrator makes the wire go round the core in two loops. Again the induced voltage is read and a doubling is observed. Then make the wire go round the core three times (see {numref}`Figure {number} <5k3002/figure_2.png>`). And so on, as long as the length of the wire enables it.
+Then the demonstrator makes the wire go round the core in two loops. Again the induced voltage is read and a doubling is observed. Then make the wire go round the core three times (see {numref}`Figure {number} <5k3002_figure_2.png>`). And so on, as long as the length of the wire enables it.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5k3002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5k3002/figure_2.png
----
.
```
diff --git a/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/5K4001.md b/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/5K4001.md
index 492e184c..26244cea 100644
--- a/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/5K4001.md
+++ b/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/5K4001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5k4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5k4001_figure_0.png
+
.
```
@@ -30,25 +29,23 @@ When the front wheel is given a turn by hand, the wheel will continue turning, d
When you give the wheel a push into the other direction the dynamo will also drive the wheel into that direction.
## Explanation
-Inside the dynamo we find a static coil and a rotating permanent ceramic magnet. The ceramic magnet has 8 poles and turns inside the coil (see {numref}`Figure {number} <5k4001/figure_1.png>` and a disassembled dynamo).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5k4001/figure_1.png
----
+Inside the dynamo we find a static coil and a rotating permanent ceramic magnet. The ceramic magnet has 8 poles and turns inside the coil (see {numref}`Figure {number} <5k4001_figure_1.png>` and a disassembled dynamo).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5k4001_figure_1.png
+
.
```
By means of two claw rings, whose claws fit in the inside of the coil, the magnetic North- and South pole "appear" perpendicular to the coil. Turning the magnet makes the North- and South pole switch their position. And turning the magnet will induce an emf in the coil.
-When a power supply makes an ac current flow through the coil, the claws change their North-South polarity continuously, attracting and repelling the poles of the ceramic magnet. When the magnet has the right speed, movement into one direction will continue (see {numref}`Figure {number} <5k4001/figure_2.png>`a).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5k4001/figure_2.png
----
+When a power supply makes an ac current flow through the coil, the claws change their North-South polarity continuously, attracting and repelling the poles of the ceramic magnet. When the magnet has the right speed, movement into one direction will continue (see {numref}`Figure {number} <5k4001_figure_2.png>`a).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5k4001_figure_2.png
+
.
```
-When the magnet is too slow just a little bit the driving momentum, $F \Delta \Delta$ on the magnet becomes smaller and smaller, because $\Delta t$ becomes smaller and smaller and the magnet will stop (see {numref}`Figure {number} <5k4001/figure_2.png>`b).
+When the magnet is too slow just a little bit the driving momentum, $F \Delta \Delta$ on the magnet becomes smaller and smaller, because $\Delta t$ becomes smaller and smaller and the magnet will stop (see {numref}`Figure {number} <5k4001_figure_2.png>`b).
The magnet cannot start turning by itself because its rotational inertia is too high to pick up the right speed within $0.01 \mathrm{sec}$. When standing still the magnet is repelled and then attracted and so on, so it will make a vibrating movement.
@@ -60,7 +57,6 @@ See 9:59 minutes
```{iframe} https://www.youtube.com/watch?v=VMt43LqsvDo&t=615s
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
diff --git a/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/qr_images/qrcode_watch_v_VMt43LqsvDo_t_615s.svg b/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/qr_images/qrcode_watch_v_VMt43LqsvDo_t_615s.svg
new file mode 100644
index 00000000..37677218
--- /dev/null
+++ b/book/book/5 EM/5K electromagnetic induction/5K40 Motors and Generators/5K4001 Electric Motor/qr_images/qrcode_watch_v_VMt43LqsvDo_t_615s.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/5L2001.md b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/5L2001.md
index 11a45dee..b5f6f34d 100644
--- a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/5L2001.md
+++ b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/5L2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5l2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5l2001_figure_0.png
+
.
```
@@ -23,7 +22,7 @@ name: 5l2001/figure_0.png
- U-core with bar.
- 2 Demonstration meters.
- Safety connection box .
-- Measuring junction box (See {numref}`Figure {number} <5l2001/figure_4.png>`).
+- Measuring junction box (See {numref}`Figure {number} <5l2001_figure_4.png>`).
- Net-adapter for mobile telephone (or other appliance).
## Safety
@@ -32,27 +31,25 @@ name: 5l2001/figure_0.png
## Presentation
-The circuit is build as shown in {numref}`Figure {number} <5l2001/figure_1.png>` and in Diagram. First we show the circuit setup to the students and then connect the two Voltmeters.
+The circuit is build as shown in {numref}`Figure {number} <5l2001_figure_1.png>` and in Diagram. First we show the circuit setup to the students and then connect the two Voltmeters.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5l2001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5l2001_figure_1.png
+
.
```
-1. Connecting the $220 \mathrm{~V}$ to the circuit makes the lamp glows strongly (see {numref}`Figure {number} <5l2001/figure_2.png>`A ). The Voltmeter connected to the lamp reads almost $220 \mathrm{~V}$ : All voltage appears across the lamp; just a very little voltage is read across the coil.
+1. Connecting the $220 \mathrm{~V}$ to the circuit makes the lamp glows strongly (see {numref}`Figure {number} <5l2001_figure_2.png>`A ). The Voltmeter connected to the lamp reads almost $220 \mathrm{~V}$ : All voltage appears across the lamp; just a very little voltage is read across the coil.
***Conclusion*** is that only a very small emf of self-inductance is generated in the coil.
2. The bar is partly shifted on to the U-core. As soon as the bar touches the second leg of the $U$-core the lamp dims (see figure $2 B$ ). the Voltmeter across the lamp shows a lower voltage now and at the same time we observe an increase in voltage across the coil.
***Conclusion*** is that there is now a higher emf of self-inductance that opposes the $220 \mathrm{~V}$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5l2001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5l2001_figure_2.png
+
.
```
@@ -62,22 +59,20 @@ name: 5l2001/figure_2.png
Shifting the bar back and forth across the U-core makes the lamp dim less or more.
-4. Finally we disconnect the lamp. Now only the self-inductance is connected to the $220 \mathrm{~V}$ (see {numref}`Figure {number} <5l2001/figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 5l2001/figure_3.png
----
+4. Finally we disconnect the lamp. Now only the self-inductance is connected to the $220 \mathrm{~V}$ (see {numref}`Figure {number} <5l2001_figure_3.png>`).
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 5l2001_figure_3.png
+
.
```
Now the effect of self-inductance is most clear: the voltmeter reads $220 \mathrm{~V}$ across the coil, and only a small current is flowing (we measure $0.4 \mathrm{~A}$ ). When there would be no self-inductance, the current would be $220 \mathrm{~V} / 2.5 \Omega=88 \mathrm{~A}$ !
-Conclusion is that the emf of self-inductance really opposes the applied voltage. 5. The same demonstration is performed with a commercial net-adapter (used as charger for a mobile telephone; see {numref}`Figure {number} <5l2001/figure_4.png>`). Here also only the primary coil of the adapter is connected to the mains. We read a current of only $0.3 \mathrm{~mA}$!
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 5l2001/figure_4.png
----
+Conclusion is that the emf of self-inductance really opposes the applied voltage. 5. The same demonstration is performed with a commercial net-adapter (used as charger for a mobile telephone; see {numref}`Figure {number} <5l2001_figure_4.png>`). Here also only the primary coil of the adapter is connected to the mains. We read a current of only $0.3 \mathrm{~mA}$!
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 5l2001_figure_4.png
+
.
```
@@ -89,19 +84,17 @@ $L=\frac{\mu_{r} \mu_{0} N^{2} A}{l} L=\frac{\mu_{r} \mu_{0} N^{2} A}{l}$. This
## Remarks
- The core on the bar makes a lot of noise. This is a $100 \mathrm{~Hz}$ mains hum due to the mains frequency $(50 \mathrm{~Hz})$.
- The effect of self-inductance can also be translated into impedance of the circuit. In our demonstration 4. the circuit shows an impedance of $220 \mathrm{~V} / 0.4 \mathrm{~A}=550 \Omega$ instead of the $2.5 \Omega$ of the copper coil.
-- In figure B we read $V_{\text {coil }}=130 \mathrm{~V}$ and $V_{\text {lamp }}=110 \mathrm{~V}$. Students easily read this as a total of $240 \mathrm{~V}$, so higher than the applied $220 \mathrm{~V}$. Phase-shift between these two voltages is responsible for that. The situation must be something like {numref}`Figure {number} <5l2001/figure_5.png>` below shows.
-```{figure} figures/figure_5.png
----
-width: 70%
-name: 5l2001/figure_5.png
----
+- In figure B we read $V_{\text {coil }}=130 \mathrm{~V}$ and $V_{\text {lamp }}=110 \mathrm{~V}$. Students easily read this as a total of $240 \mathrm{~V}$, so higher than the applied $220 \mathrm{~V}$. Phase-shift between these two voltages is responsible for that. The situation must be something like {numref}`Figure {number} <5l2001_figure_5.png>` below shows.
+```{figure} figures/figure_5.png
+:width: 70%
+:label: 5l2001_figure_5.png
+
.
```
## Video Rhett Allain
```{iframe} https://www.youtube.com/watch?v=J2epiOv40Oo
:width: 70%
-:height: 400px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
```
diff --git a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg
new file mode 100644
index 00000000..457ae17a
--- /dev/null
+++ b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2001 Self Inductance in AC Circuit/qr_images/qrcode_watch_v_J2epiOv40Oo.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2002 Phase/5L2002.md b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2002 Phase/5L2002.md
index 7e6f983a..b2e8ad5d 100644
--- a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2002 Phase/5L2002.md
+++ b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2002 Phase/5L2002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5l2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5l2002_figure_0.png
+
.
```
@@ -28,12 +27,11 @@ name: 5l2002/figure_0.png
## Presentation
-Switch on the signal generator and set the frequency at $0,3 \mathrm{~Hz}$. Build the circuit with the resistor (see {numref}`Figure {number} <5l2002/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5l2002/figure_1.png
----
+Switch on the signal generator and set the frequency at $0,3 \mathrm{~Hz}$. Build the circuit with the resistor (see {numref}`Figure {number} <5l2002_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5l2002_figure_1.png
+
.
```
Adjust the voltage until about $3 \mathrm{~V}$ amplitude is read on the voltmeter. Observing also the A-meter scale, it is observed that the applied voltage and current are in phase.
diff --git a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2003 LRC Circuits/5L2003.md b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2003 LRC Circuits/5L2003.md
index 4f3ed7ab..e8f58bc8 100644
--- a/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2003 LRC Circuits/5L2003.md
+++ b/book/book/5 EM/5L AC circuits/5L20 LCR Circuits AC/5L2003 LRC Circuits/5L2003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5L2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5L2003_figure_0.png
+
.
```
@@ -28,12 +27,11 @@ name: 5L2003/figure_0.png
## Presentation
- The circuit is made as shown in Diagram and {numref}`Figure {number} <5l2003/figure_1.png>`.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5l2003/figure_1.png
----
+ The circuit is made as shown in Diagram and {numref}`Figure {number} <5l2003_figure_1.png>`.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5l2003_figure_1.png
+
.
```
C is made $1 u F$. The value of $R$ is made zero. The voltage of the signal generator is made $6 \mathrm{~V}$.
@@ -67,14 +65,13 @@ These results are similar to those measured in the seriescircuit but now the que
* Supposing the frequency extremely low (dc) it is clear that a capacitor conducts no current (it is an insulator) and so it will have a very high resistance. At low frequencies the capacitor is charged in a time very small compared to the period time of the ac-source and so the capacitor has constantly the same voltage (almost) as the source. This voltage opposes the source voltage and so no current will flow. At very high frequencies the charging time of the capacitor is equal to or larger than the period time and so the capacitor is charging (and discharging) continuously: a current is flowing.
* At extreme low frequencies the coil has a very low inductance (Dt=large) and only a voltage due to its resistance of the copper wires appears across its terminals. At high frequencies the coil will produce a high induced voltage ($Dt$=small), so at high frequencies a high voltage can be expected across it. In this qualitative way the opposite frequency-response of C and L can be talked into the students. A more thorough analysis is needed to understand all the results that can be shown in this demonstration. A phase-diagram is needed.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5l2003/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5l2003_figure_2.png
+
.
```
-Many textbooks show these diagrams. {numref}`Figure {number} <5l2003/figure_2.png>` shows the diagrams that apply to our demonstrations.
+Many textbooks show these diagrams. {numref}`Figure {number} <5l2003_figure_2.png>` shows the diagrams that apply to our demonstrations.
The explanation of the results measured in the parallel circuit can be explained using a current phase-diagram.
diff --git a/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1001 Electromagnetic Waves Lecher Lines/5N1001.md b/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1001 Electromagnetic Waves Lecher Lines/5N1001.md
index c96173a8..005613c9 100644
--- a/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1001 Electromagnetic Waves Lecher Lines/5N1001.md
+++ b/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1001 Electromagnetic Waves Lecher Lines/5N1001.md
@@ -8,19 +8,17 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5n1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5n1001_figure_0.png
+
.
```
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5n1001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5n1001_figure_1.png
+
.
```
@@ -51,7 +49,7 @@ name: 5n1001/figure_1.png
- Metal grated sheet
- Water tank with long and short $\lambda / 2$ dipole with lamps $3.8 \mathrm{~V} / 70 \mathrm{~mA}$.
- Demineralized water.
-- Ohp-sheet with {numref}`Figure {number} <5n1001/figure_2.png>`.
+- Ohp-sheet with {numref}`Figure {number} <5n1001_figure_2.png>`.
## Safety
@@ -69,17 +67,16 @@ The metal two-legged loop, having a length of $35 \mathrm{~cm}$ (Lecher-line), i
This pattern can be understood when showing that a full standing E-wave fits into the total length of $70 \mathrm{~cm}$. Then there are E-nodes at $17.5 \mathrm{~cm}(\lambda / 4)$ and at $52.5 \mathrm{~cm}(3 \lambda / 4)$. At $35 \mathrm{~cm}(\lambda / 2)$ there is an antinode. Figure1A shows this E-pattern and clarifies that maximum potential difference occurs between $\mathrm{S}$ and $\mathrm{S}$. (S-S is an in intensity oscillating dipole.)
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5n1001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5n1001_figure_2.png
+
.
```
Then the coil with $n=10.000$ is connected to a $100 \mathrm{vA}$ demonstration meter via the h.f. rectifier diode (see Diagram A). The coil is placed on a cart and slides slowly and close ( $2 \mathrm{~cm}$ distance) along one of the legs of the conducting rods. The demonstration meter shows where induction along the leg happens, it shows the nodes and anti-nodes of the magnetic field $B$ along the conducting rod; so it shows the standing current pattern in the conducting rod. We find B-nodes and anti-nodes on the places opposing those of the E-field. (see also: Remarks)
-Then longer two-legged loops are build (Lecher system; see Diagram B). This Lecher system makes i possible to investigate the standing electromagnetic wave in longer variants, either shorted or open ended ({numref}`Figure {number} <5n1001/figure_2.png>`B, C and D are possible examples). Sliding the lamp-probe and/or the coil in these examples will strengthen the idea of standing E- and B-waves on the conductors.
+Then longer two-legged loops are build (Lecher system; see Diagram B). This Lecher system makes i possible to investigate the standing electromagnetic wave in longer variants, either shorted or open ended ({numref}`Figure {number} <5n1001_figure_2.png>`B, C and D are possible examples). Sliding the lamp-probe and/or the coil in these examples will strengthen the idea of standing E- and B-waves on the conductors.
(When needed to illustrate that a standing wave is related to length, the demonstration ["Handheld standing waves"](/book/3%20oscillations%20and%20waves/3B%20wave/3B22%20Standing/3B2202%20Handheld%20Standing%20Waves/3B2202.md) in this database can be used. Also ["Kundt's tube"](/book/3%20oscillations%20and%20waves/3B%20wave/3B22%20Standing/3B2203%20Kundts%20Tube/3B2203.md) can be used as an analogy.)
@@ -101,7 +98,7 @@ Move the metal rod from the receiver dipole towards the transmitter and the lamp
## Explanation
-{numref}`Figure {number} <5n1001/figure_2.png>` explains the polarized E-field that is produced by the loop dipole. This loop dipole is effectively the two-legged loop of {numref}`Figure {number} <5n1001/figure_2.png>`A, but folded in a different way. Figure1E makes clear that there is a resulting E-field pulsating with a frequency of $434 \mathrm{MHz}$. The explanation is already done in the description "PresentationXX". More details can be found in the presented "SourcesXX".
+{numref}`Figure {number} <5n1001_figure_2.png>` explains the polarized E-field that is produced by the loop dipole. This loop dipole is effectively the two-legged loop of {numref}`Figure {number} <5n1001_figure_2.png>`A, but folded in a different way. Figure1E makes clear that there is a resulting E-field pulsating with a frequency of $434 \mathrm{MHz}$. The explanation is already done in the description "PresentationXX". More details can be found in the presented "SourcesXX".
## Remarks
- The $\pi/2$ phase-shift between $E$ and $B$ on the Lecher line should not be confused with the in-phase situation of $E$ and $B$ of the EM-field in vacuum (air). The in-phase situation belongs to the EM-field as detected relatively far away from the emitting dipole.
diff --git a/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1002 Microwave Oven Standing Waves/5N1002.md b/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1002 Microwave Oven Standing Waves/5N1002.md
index 563ee707..efcf693b 100644
--- a/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1002 Microwave Oven Standing Waves/5N1002.md
+++ b/book/book/5 EM/5N electromagnetic radiation/5N10 Transmission Lines and Antennas/5N1002 Microwave Oven Standing Waves/5N1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 5n1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 5n1002_figure_0.png
+
.
```
@@ -30,23 +29,21 @@ name: 5n1002/figure_0.png
## Presentation
-Shortly the operation of the microwave oven is explained to the students. This is done by showing the cavity magnetron to them and explaining its operation (see {numref}`Figure {number} <5n1002/figure_1.png>`). See for instance: https://www.radartutorial.eu/08.transmitters/tx08.en.html
+Shortly the operation of the microwave oven is explained to the students. This is done by showing the cavity magnetron to them and explaining its operation (see {numref}`Figure {number} <5n1002_figure_1.png>`). See for instance: https://www.radartutorial.eu/08.transmitters/tx08.en.html
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 5n1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 5n1002/figure_1.png
----
.
```
-The oven is switched ON for around 2 minutes. After around 30 seconds it is observed that the marsh-mallows rise. After two minutes it is clearly observed that the rising occurs only at certain spots (see {numref}`Figure {number} <5n1002/figure_2.png>`).
+The oven is switched ON for around 2 minutes. After around 30 seconds it is observed that the marsh-mallows rise. After two minutes it is clearly observed that the rising occurs only at certain spots (see {numref}`Figure {number} <5n1002_figure_2.png>`).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 5n1002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 5n1002/figure_2.png
----
.
```
We measure $d =10 \mathrm{~cm}$.
@@ -55,7 +52,7 @@ name: 5n1002/figure_2.png
The rising of the marshmallows at certain spots only, shows that there is heating only at certain spots. This can be explained by assuming a standing em-wave in the cavity that the oven is.
### Discussion:
- Knowing that the magnetron-frequency is $2.45 \mathrm{Ghz}$, makes that the wavelength in air of the em-wave equals $12.2 \mathrm{~cm}$. Then possible standing waves are standing waves with $n(12.2) \mathrm{cm}[n=1,2,3, \ldots]$, and we expect heating at multiples of half wavelength distances, so at $\mathrm{n}(6.1) \mathrm{cm}$. We measure heating hills at $10 \mathrm{~cm}$ separation (see {numref}`Figure {number} <5n1002/figure_2.png>`). This means that the standing wave has a wavelength of $20 \mathrm{~cm}$. This can only mean that the frequency of the em-wave inside the oven is less than $2.45 \mathrm{MHz}$. supposing it is half that frequency, then we expect standing waves with $\mathrm{n}(24.4) \mathrm{cm}$, and heating hills at $12.2 \mathrm{~cm}$ separation. That we measure $10 \mathrm{~cm}$ can be caused by the dielectric constant of marshmallows being $>1$, causing a smaller wavelength inside the marshmallows.
+ Knowing that the magnetron-frequency is $2.45 \mathrm{Ghz}$, makes that the wavelength in air of the em-wave equals $12.2 \mathrm{~cm}$. Then possible standing waves are standing waves with $n(12.2) \mathrm{cm}[n=1,2,3, \ldots]$, and we expect heating at multiples of half wavelength distances, so at $\mathrm{n}(6.1) \mathrm{cm}$. We measure heating hills at $10 \mathrm{~cm}$ separation (see {numref}`Figure {number} <5n1002_figure_2.png>`). This means that the standing wave has a wavelength of $20 \mathrm{~cm}$. This can only mean that the frequency of the em-wave inside the oven is less than $2.45 \mathrm{MHz}$. supposing it is half that frequency, then we expect standing waves with $\mathrm{n}(24.4) \mathrm{cm}$, and heating hills at $12.2 \mathrm{~cm}$ separation. That we measure $10 \mathrm{~cm}$ can be caused by the dielectric constant of marshmallows being $>1$, causing a smaller wavelength inside the marshmallows.
## Sources
* https://www.radartutorial.eu/08.transmitters/tx08.en.html
\ No newline at end of file
diff --git a/book/book/6 optics/6A geometrical optics/6A01 Speed of Light/6A0101 Foucault Michelson/6A0101.md b/book/book/6 optics/6A geometrical optics/6A01 Speed of Light/6A0101 Foucault Michelson/6A0101.md
index d1680de6..bf50f43c 100644
--- a/book/book/6 optics/6A geometrical optics/6A01 Speed of Light/6A0101 Foucault Michelson/6A0101.md
+++ b/book/book/6 optics/6A geometrical optics/6A01 Speed of Light/6A0101 Foucault Michelson/6A0101.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a0101/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a0101_figure_0.png
+
.
```
@@ -33,30 +32,28 @@ Make the laser beam go as horizontal as possible; careful alignment is essential
The $+5 \mathrm{~m}$-lens is positioned at about $5 \mathrm{~m}$ distance from the rotating mirror.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a0101/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a0101_figure_1.png
+
.
```
-Image-distance $b$ (see {numref}`Figure {number} <6a0101/figure_1.png>`A) is chosen such that the image of the first mirror $\left(\mathrm{M}_{1}\right)$ is sharp at $M_{3}\left(\frac{1}{f}=\frac{1}{r+f}+\frac{1}{b}\right)$. (In our assembly this means that $b$ is around 25 meters.) Lens $+5 \mathrm{~m}$ and $M_{3}$ are carefully adjusted until, in the right postion of the rotating mirror $\left(M_{r}\right)$ the laserbeam is reflected to the camera (the camera and $M_{1}$ have the same distance to $\mathrm{M}_{3}$ ). Making the rotating mirror turn at its highest speed (about 500 rev. per second) the light spot displaces, in our assembly, the whole width of the monitor screen. This displacement is calibrated by placing a plastic ruler between the grey filter and the camera (see {numref}`Figure {number} <6a0101/figure_2.png>`A).
+Image-distance $b$ (see {numref}`Figure {number} <6a0101_figure_1.png>`A) is chosen such that the image of the first mirror $\left(\mathrm{M}_{1}\right)$ is sharp at $M_{3}\left(\frac{1}{f}=\frac{1}{r+f}+\frac{1}{b}\right)$. (In our assembly this means that $b$ is around 25 meters.) Lens $+5 \mathrm{~m}$ and $M_{3}$ are carefully adjusted until, in the right postion of the rotating mirror $\left(M_{r}\right)$ the laserbeam is reflected to the camera (the camera and $M_{1}$ have the same distance to $\mathrm{M}_{3}$ ). Making the rotating mirror turn at its highest speed (about 500 rev. per second) the light spot displaces, in our assembly, the whole width of the monitor screen. This displacement is calibrated by placing a plastic ruler between the grey filter and the camera (see {numref}`Figure {number} <6a0101_figure_2.png>`A).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a0101_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a0101/figure_2.png
----
.
```
-Shadow projection of the mm-lines on the sensitive layer of the camera show these lines on the monitor (we have $7 \mathrm{~mm}$ across the full width of the monitor screen; see {numref}`Figure {number} <6a0101/figure_2.png>`B). The geometry of the assembly makes it possible to link the rotation of the mirror to the displacement on the monitor screen (we have a displacement of around
+Shadow projection of the mm-lines on the sensitive layer of the camera show these lines on the monitor (we have $7 \mathrm{~mm}$ across the full width of the monitor screen; see {numref}`Figure {number} <6a0101_figure_2.png>`B). The geometry of the assembly makes it possible to link the rotation of the mirror to the displacement on the monitor screen (we have a displacement of around
$2.5 \mathrm{~mm}$ on the camera, corresponding to $\phi=\frac{d}{2 r}=\frac{2.5 \times 10^{-3}}{2 \times 2.6}=0.48 \times 10^{-3} \mathrm{rad}$ of $\mathrm{M}_{\mathrm{r}}$ ).
### Demonstration:
-The laser is switched on and the light path is shown to the students. By hand the rotating mirror is turned until a flash is seen on the monitor screen. In this position the light path is as drawn in the Diagram. The principle of operation is explained to the students: In the time it takes the light beam to travel the distance $M_{r}-M_{3}-M_{r}$ the rotating mirror has made a little angle ( $\varphi$ ). This is observed on the monitor screen (angle $2 \varphi$, see {numref}`Figure {number} <6a0101/figure_1.png>`B).
+The laser is switched on and the light path is shown to the students. By hand the rotating mirror is turned until a flash is seen on the monitor screen. In this position the light path is as drawn in the Diagram. The principle of operation is explained to the students: In the time it takes the light beam to travel the distance $M_{r}-M_{3}-M_{r}$ the rotating mirror has made a little angle ( $\varphi$ ). This is observed on the monitor screen (angle $2 \varphi$, see {numref}`Figure {number} <6a0101_figure_1.png>`B).
Also the calibration is explained to the students.
diff --git a/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1001 Confusing Mirrors/6A1001.md b/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1001 Confusing Mirrors/6A1001.md
index 04c7d979..1bc30e12 100644
--- a/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1001 Confusing Mirrors/6A1001.md
+++ b/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1001 Confusing Mirrors/6A1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a1001_figure_0.png
+
.
```
@@ -29,35 +28,32 @@ name: 6a1001/figure_0.png
As is known very well,the image of the left hand is a right hand. But why are top and down not interchanged?.
-2. Look into the hinged double mirror (see {numref}`Figure {number} <6a1001/figure_1.png>`), the angle between the two mirrors ( $\alpha$ is larger than $90^{\circ}$. Moving your eyes you see left and right an image of your head ({numref}`Figure {number} <6a1001/figure_1.png>`A). Left/right is interchanged in the images.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a1001/figure_1.png
----
+2. Look into the hinged double mirror (see {numref}`Figure {number} <6a1001_figure_1.png>`), the angle between the two mirrors ( $\alpha$ is larger than $90^{\circ}$. Moving your eyes you see left and right an image of your head ({numref}`Figure {number} <6a1001_figure_1.png>`A). Left/right is interchanged in the images.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a1001_figure_1.png
+
.
```
-Now make the $\alpha$ smaller than $90^{\circ}$. At around $\alpha=60^{\circ}$ you see four images (see {numref}`Figure {number} <6a1001/figure_1.png>`B): The image in the left mirror is again imaged in the right mirror and viceversa.
+Now make the $\alpha$ smaller than $90^{\circ}$. At around $\alpha=60^{\circ}$ you see four images (see {numref}`Figure {number} <6a1001_figure_1.png>`B): The image in the left mirror is again imaged in the right mirror and viceversa.
-Slowly the $\alpha$ is made smaller and the two imaged images fall together (at $\alpha=90^{\circ}$ ) (see {numref}`Figure {number} <6a1001/figure_1.png>`C). Move your head on one side to observe this particular image and see that in this image left is still left.
+Slowly the $\alpha$ is made smaller and the two imaged images fall together (at $\alpha=90^{\circ}$ ) (see {numref}`Figure {number} <6a1001_figure_1.png>`C). Move your head on one side to observe this particular image and see that in this image left is still left.
-3. Look at the revolving double mirror (see {numref}`Figure {number} <6a1001/figure_2.png>`A). Turn it round slowly and observe that you are upside down (your image is rotated $180^{\circ}$ when the mirror.
+3. Look at the revolving double mirror (see {numref}`Figure {number} <6a1001_figure_2.png>`A). Turn it round slowly and observe that you are upside down (your image is rotated $180^{\circ}$ when the mirror.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a1001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a1001/figure_2.png
----
.
```
-4. Look (close one eye) into the arrangement of three planar mirrors (see {numref}`Figure {number} <6a1001/figure_3.png>`).
+4. Look (close one eye) into the arrangement of three planar mirrors (see {numref}`Figure {number} <6a1001_figure_3.png>`).
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6a1001/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6a1001_figure_3.png
+
.
```
Observe:
diff --git a/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1002 Corner Cube/6A1002.md b/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1002 Corner Cube/6A1002.md
index e45eb5e3..40bd8d68 100644
--- a/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1002 Corner Cube/6A1002.md
+++ b/book/book/6 optics/6A geometrical optics/6A10 Reflection From Flat Surfaces/6A1002 Corner Cube/6A1002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a1002_figure_0.png
+
.
```
@@ -31,22 +30,20 @@ Directing a laser beam towards a corner cube produces a reflection back to the l
## Explanation
In a planar mirror the image and object are equidistant from the mirror surface. But there is also inversion:
-a right-handed coordinate system is converted into a left-handed one (see {numref}`Figure {number} <6a1002/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a1002/figure_1.png
----
+a right-handed coordinate system is converted into a left-handed one (see {numref}`Figure {number} <6a1002_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a1002_figure_1.png
+
.
```
We see that after reflection $a_1$ has changed into $-a_1$, while $a_2$ and $a_3$ remain the same. Vector notation is applied to treat this.
-{numref}`Figure {number} <6a1002/figure_2.png>` shows that reflection in three mutually perpendicular mirrors $(x z, x y, y z)$ will produce ray (vector) inversion. Three reflections occur:
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a1002/figure_2.png
----
+{numref}`Figure {number} <6a1002_figure_2.png>` shows that reflection in three mutually perpendicular mirrors $(x z, x y, y z)$ will produce ray (vector) inversion. Three reflections occur:
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a1002_figure_2.png
+
.
```
diff --git a/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4001 Chromatic Aberration/6A4001.md b/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4001 Chromatic Aberration/6A4001.md
index 3b7ca8a3..0fea760e 100644
--- a/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4001 Chromatic Aberration/6A4001.md
+++ b/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4001 Chromatic Aberration/6A4001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a4001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a4001_figure_0.png
+
.
```
@@ -43,12 +42,11 @@ When the $150 \mathrm{~mm}$ single lens is replaced by the doublet of $150 \math
## Explanation
Since the thin-lens equation $\frac{1}{f}=\left(n_{t}-1\right)\left(\frac{1}{R_{1}}-\frac{1}{R_{2}}\right)$ is wavelength-dependent via $n_{1}(\lambda)$
-(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6a4001/figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a4001/figure_1.png
----
+(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6a4001_figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a4001_figure_1.png
+
.
```
In general $n_{1}(\lambda)$ decreases with wavelength over the visible region, and thus $f(\lambda)$ increases with $\lambda$. And when $f(\lambda)$ increases with $\lambda$, then also the image-distance increases with $\lambda$ (object-distance is constant). The demonstration shows this: the red image being sharp at a larger distance than the blue image.
diff --git a/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4002 Curved Lightbeams/6A4002.md b/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4002 Curved Lightbeams/6A4002.md
index 47541c4b..4406457e 100644
--- a/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4002 Curved Lightbeams/6A4002.md
+++ b/book/book/6 optics/6A geometrical optics/6A40 Refractive Index/6A4002 Curved Lightbeams/6A4002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a4002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a4002_figure_0.png
+
.
```
@@ -25,11 +24,10 @@ name: 6a4002/figure_0.png
## Figures
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a4002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a4002_figure_1.png
+
.
```
diff --git a/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/6A4201.md b/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/6A4201.md
index 357af5be..50e20f44 100644
--- a/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/6A4201.md
+++ b/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/6A4201.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a4201/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a4201_figure_0.png
+
.
```
@@ -33,17 +32,8 @@ name: 6a4201/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/_OfXNZzgFr4?si=adsBQ7dZleDPpNUT
+```
### Preparation.
@@ -53,37 +43,35 @@ Mention and show to the students the relevant parts of the demonstration: "air";
### 1. $n_{i} \leq n_t$.
-- First the reflection and refraction at the boundary between air and the acrylic block is shown at different angles of incidence. The starting position is at $0^{\circ}$ (coinciding with the normal to the flat surface of the acrylic block) and slowly the angle of incidence is increased up to $90^{\circ}$ (see {numref}`Figure {number} <6a4201/figure_1.png>`A).
+- First the reflection and refraction at the boundary between air and the acrylic block is shown at different angles of incidence. The starting position is at $0^{\circ}$ (coinciding with the normal to the flat surface of the acrylic block) and slowly the angle of incidence is increased up to $90^{\circ}$ (see {numref}`Figure {number} <6a4201_figure_1.png>`A).
Repeating this demo you can draw the attention to the difference in intensities of the reflected and refracted beam
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a4201/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a4201_figure_1.png
+
.
```
-- Then a Polaroid filter is placed in the laser beam to make the E-field parallel to the plane of incidence: Show the students that the green stick indicating the direction of the resulting E-field is in the plane of the large disc: p-polarization (see Diagram B). Again reflection and refraction is observed while increasing the angle of incidence from $0-90^{\circ}$. Clearly observable now is the disappearance of the reflected beam at around $56^{\circ}$ (see {numref}`Figure {number} <6a4201/figure_1.png>`B). This shows Brewster's angle. At Brewster's angle it is also observable that between the disappeared reflected beam and the refracted beam there is an angle of $90^{\circ}$.
+- Then a Polaroid filter is placed in the laser beam to make the E-field parallel to the plane of incidence: Show the students that the green stick indicating the direction of the resulting E-field is in the plane of the large disc: p-polarization (see Diagram B). Again reflection and refraction is observed while increasing the angle of incidence from $0-90^{\circ}$. Clearly observable now is the disappearance of the reflected beam at around $56^{\circ}$ (see {numref}`Figure {number} <6a4201_figure_1.png>`B). This shows Brewster's angle. At Brewster's angle it is also observable that between the disappeared reflected beam and the refracted beam there is an angle of $90^{\circ}$.
- Repeating this demo the difference in intensities between the reflected and refracted beam is observed. This observation can be related to the projected graph of the amplitude coefficients of reflection and transmission (see {numref}`Figure {number} <6a4201/figure_2.png>` in Brewster's angle (1)" in this database).
+ Repeating this demo the difference in intensities between the reflected and refracted beam is observed. This observation can be related to the projected graph of the amplitude coefficients of reflection and transmission (see {numref}`Figure {number} <6a4201_figure_2.png>` in Brewster's angle (1)" in this database).
-- Finally the Polaroid filter is rotated $90^{\circ}$ to make the E-field normal to the plane of incidence (perpendicular to the large disc: $s$-polarization). Again reflection and refraction is observed but no Brewster's angle appears (see {numref}`Figure {number} <6a4201/figure_1.png>`C).
+- Finally the Polaroid filter is rotated $90^{\circ}$ to make the E-field normal to the plane of incidence (perpendicular to the large disc: $s$-polarization). Again reflection and refraction is observed but no Brewster's angle appears (see {numref}`Figure {number} <6a4201_figure_1.png>`C).
2. $n_{i}>n_{t}$
-- The Polaroid filter is removed and the laser beam now enters the circular side of the acrylic block. (Upon entering the acrylic block the laser beam is always perpendicular to the surface of the block. So there is no refraction upon entering the acrylic block.) Again the angle of incidence on the boundary between acrylic block and air is increased from 0 up to $90^{\circ}$ and reflection and refraction is observed (see {numref}`Figure {number} <6a4201/figure_2.png>`A). When the angle of incidence comes close to $42^{\circ}$, the refracted beam approaches $90^{\circ}$ and then disappears.
+- The Polaroid filter is removed and the laser beam now enters the circular side of the acrylic block. (Upon entering the acrylic block the laser beam is always perpendicular to the surface of the block. So there is no refraction upon entering the acrylic block.) Again the angle of incidence on the boundary between acrylic block and air is increased from 0 up to $90^{\circ}$ and reflection and refraction is observed (see {numref}`Figure {number} <6a4201_figure_2.png>`A). When the angle of incidence comes close to $42^{\circ}$, the refracted beam approaches $90^{\circ}$ and then disappears.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a4201_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a4201/figure_2.png
----
.
```
At this point the angle of incidence is called 'critical angle' and there is total internal reflection in the acrylic block.
--The Polaroid filter is used to make the E-field p-polarized. The demo is repeated and a Brewster's angle appears at $34^{\circ}$. Also check the $90^{\circ}$ angle between the refracted and disappeared reflected beam (see {numref}`Figure {number} <6a4201/figure_2.png>`B).
+-The Polaroid filter is used to make the E-field p-polarized. The demo is repeated and a Brewster's angle appears at $34^{\circ}$. Also check the $90^{\circ}$ angle between the refracted and disappeared reflected beam (see {numref}`Figure {number} <6a4201_figure_2.png>`B).
--Finally s-polarization is investigated: no Brewster's angle appears (see {numref}`Figure {number} <6a4201/figure_2.png>`C).
+-Finally s-polarization is investigated: no Brewster's angle appears (see {numref}`Figure {number} <6a4201_figure_2.png>`C).
## Explanation
Calculating Brewster's angle we use $\theta=\arctan \frac{n_{t}}{n_{i}} \cdot n_{\text {air }}=1$ and $n_{\text {acrylic block }}=1.5$. With these values we get in our first demonstration $\theta_{b}=\arctan \frac{1.5}{1}=56^{\circ}$, and in our second demonstration $\theta_{b}=\arctan \frac{1}{1.5}=34^{\circ}$.
@@ -100,7 +88,6 @@ For more explanation see also the two other Brewster's angle demos in this datab
```{iframe} https://www.youtube.com/watch?v=13_T9UZRjvA
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
```
diff --git a/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg b/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg
new file mode 100644
index 00000000..d58256ec
--- /dev/null
+++ b/book/book/6 optics/6A geometrical optics/6A42 Refraction at Flat Surfaces/6A4201 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/6A4401.md b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/6A4401.md
index 911b4e3e..66db1ec3 100644
--- a/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/6A4401.md
+++ b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/6A4401.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a4401/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a4401_figure_0.png
+
.
```
@@ -34,17 +33,8 @@ name: 6a4401/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/_OfXNZzgFr4?si=adsBQ7dZleDPpNUT
+```
### Preparation.
@@ -54,37 +44,35 @@ Mention and show to the students the relevant parts of the demonstration: "air";
### 1. $n_{i} \leq n_t$.
-- First the reflection and refraction at the boundary between air and the acrylic block is shown at different angles of incidence. The starting position is at $0^{\circ}$ (coinciding with the normal to the flat surface of the acrylic block) and slowly the angle of incidence is increased up to $90^{\circ}$ (see {numref}`Figure {number} <6a4201/figure_1.png>`A).
+- First the reflection and refraction at the boundary between air and the acrylic block is shown at different angles of incidence. The starting position is at $0^{\circ}$ (coinciding with the normal to the flat surface of the acrylic block) and slowly the angle of incidence is increased up to $90^{\circ}$ (see {numref}`Figure {number} <6a4201_figure_1.png>`A).
Repeating this demo you can draw the attention to the difference in intensities of the reflected and refracted beam
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a4201/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a4201_figure_1.png
+
.
```
-- Then a Polaroid filter is placed in the laser beam to make the E-field parallel to the plane of incidence: Show the students that the green stick indicating the direction of the resulting E-field is in the plane of the large disc: p-polarization (see Diagram B). Again reflection and refraction is observed while increasing the angle of incidence from $0-90^{\circ}$. Clearly observable now is the disappearance of the reflected beam at around $56^{\circ}$ (see {numref}`Figure {number} <6a4201/figure_1.png>`B). This shows Brewster's angle. At Brewster's angle it is also observable that between the disappeared reflected beam and the refracted beam there is an angle of $90^{\circ}$.
+- Then a Polaroid filter is placed in the laser beam to make the E-field parallel to the plane of incidence: Show the students that the green stick indicating the direction of the resulting E-field is in the plane of the large disc: p-polarization (see Diagram B). Again reflection and refraction is observed while increasing the angle of incidence from $0-90^{\circ}$. Clearly observable now is the disappearance of the reflected beam at around $56^{\circ}$ (see {numref}`Figure {number} <6a4201_figure_1.png>`B). This shows Brewster's angle. At Brewster's angle it is also observable that between the disappeared reflected beam and the refracted beam there is an angle of $90^{\circ}$.
- Repeating this demo the difference in intensities between the reflected and refracted beam is observed. This observation can be related to the projected graph of the amplitude coefficients of reflection and transmission (see {numref}`Figure {number} <6a4201/figure_2.png>` in Brewster's angle (1)" in this database).
+ Repeating this demo the difference in intensities between the reflected and refracted beam is observed. This observation can be related to the projected graph of the amplitude coefficients of reflection and transmission (see {numref}`Figure {number} <6a4201_figure_2.png>` in Brewster's angle (1)" in this database).
-- Finally the Polaroid filter is rotated $90^{\circ}$ to make the E-field normal to the plane of incidence (perpendicular to the large disc: $s$-polarization). Again reflection and refraction is observed but no Brewster's angle appears (see {numref}`Figure {number} <6a4201/figure_1.png>`C).
+- Finally the Polaroid filter is rotated $90^{\circ}$ to make the E-field normal to the plane of incidence (perpendicular to the large disc: $s$-polarization). Again reflection and refraction is observed but no Brewster's angle appears (see {numref}`Figure {number} <6a4201_figure_1.png>`C).
2. $n_{i}>n_{t}$
-- The Polaroid filter is removed and the laser beam now enters the circular side of the acrylic block. (Upon entering the acrylic block the laser beam is always perpendicular to the surface of the block. So there is no refraction upon entering the acrylic block.) Again the angle of incidence on the boundary between acrylic block and air is increased from 0 up to $90^{\circ}$ and reflection and refraction is observed (see {numref}`Figure {number} <6a4201/figure_2.png>`A). When the angle of incidence comes close to $42^{\circ}$, the refracted beam approaches $90^{\circ}$ and then disappears.
+- The Polaroid filter is removed and the laser beam now enters the circular side of the acrylic block. (Upon entering the acrylic block the laser beam is always perpendicular to the surface of the block. So there is no refraction upon entering the acrylic block.) Again the angle of incidence on the boundary between acrylic block and air is increased from 0 up to $90^{\circ}$ and reflection and refraction is observed (see {numref}`Figure {number} <6a4201_figure_2.png>`A). When the angle of incidence comes close to $42^{\circ}$, the refracted beam approaches $90^{\circ}$ and then disappears.
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a4201_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a4201/figure_2.png
----
.
```
At this point the angle of incidence is called 'critical angle' and there is total internal reflection in the acrylic block.
--The Polaroid filter is used to make the E-field p-polarized. The demo is repeated and a Brewster's angle appears at $34^{\circ}$. Also check the $90^{\circ}$ angle between the refracted and disappeared reflected beam (see {numref}`Figure {number} <6a4201/figure_2.png>`B).
+-The Polaroid filter is used to make the E-field p-polarized. The demo is repeated and a Brewster's angle appears at $34^{\circ}$. Also check the $90^{\circ}$ angle between the refracted and disappeared reflected beam (see {numref}`Figure {number} <6a4201_figure_2.png>`B).
--Finally s-polarization is investigated: no Brewster's angle appears (see {numref}`Figure {number} <6a4201/figure_2.png>`C).
+-Finally s-polarization is investigated: no Brewster's angle appears (see {numref}`Figure {number} <6a4201_figure_2.png>`C).
## Explanation
Calculating Brewster's angle we use $\theta=\arctan \frac{n_{t}}{n_{i}} \cdot n_{\text {air }}=1$ and $n_{\text {acrylic block }}=1.5$. With these values we get in our first demonstration $\theta_{b}=\arctan \frac{1.5}{1}=56^{\circ}$, and in our second demonstration $\theta_{b}=\arctan \frac{1}{1.5}=34^{\circ}$.
@@ -101,7 +89,6 @@ For more explanation see also the two other Brewster's angle demos in this datab
```{iframe} https://www.youtube.com/watch?v=13_T9UZRjvA
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/videos, courtesy Rhett Allain.
```
diff --git a/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg
new file mode 100644
index 00000000..d58256ec
--- /dev/null
+++ b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4401 Brewsters Angle/qr_images/qrcode_watch_v_13_T9UZRjvA.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4402 Tunneling/6A4402.md b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4402 Tunneling/6A4402.md
index 2b8d61ab..227873e4 100644
--- a/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4402 Tunneling/6A4402.md
+++ b/book/book/6 optics/6A geometrical optics/6A44 Total Internal Reflection/6A4402 Tunneling/6A4402.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a4202/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a4202_figure_0.png
+
.
```
@@ -40,12 +39,11 @@ The camera and monitor are placed in order to make the gap between the paraffin
The slideway is needed in order to shift one of the paraffin wax triangles along a straight line.
-When you prepare the demonstration, use the set ups as shown in {numref}`Figure {number} <6a4202/figure_1.png>`B and -C: In {numref}`Figure {number} <6a4202/figure_1.png>`B, the meter, indicating the signal received by R1, should be equal to the signal that will be received by R2 in the situation of {numref}`Figure {number} <6a4202/figure_1.png>`C. To achieve this, careful positioning is needed for sender $\mathrm{S}$, the paraffin wax blocks and both receivers.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a4202/figure_1.png
----
+When you prepare the demonstration, use the set ups as shown in {numref}`Figure {number} <6a4202_figure_1.png>`B and -C: In {numref}`Figure {number} <6a4202_figure_1.png>`B, the meter, indicating the signal received by R1, should be equal to the signal that will be received by R2 in the situation of {numref}`Figure {number} <6a4202_figure_1.png>`C. To achieve this, careful positioning is needed for sender $\mathrm{S}$, the paraffin wax blocks and both receivers.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a4202_figure_1.png
+
.
```
## Presentation
@@ -64,11 +62,10 @@ Figure C
A triangular block of paraffine wax is placed in front of the sender $S$ as shown in Figure B. Receiver R1 has no deflection, so it receives no signal. But receiver R2 shows a deflection, and this deflection is equal to that of the previous situation (Figure A). Clearly the signal from the sender is deflected by the paraffin block towards R2. Again the comparison with glass and light can be made. (Optional: show this with a laser and a rectangular prism)
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6a4202/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6a4202_figure_2.png
+
.
```
## Figure D-E
@@ -80,7 +77,7 @@ The weirdness of this phenomenon should be stressed, by mentioning that if in si
(Optional: Show that laser light that enters a beam splitter is partially transmitted and partially deflected)
## Explanation
-Apparently, the transition from wax to air into the straight on direction towards R1, as in {numref}`Figure {number} <6a4202/figure_1.png>`C, is a barrier to the microwaves, but not completely (as in {numref}`Figure {number} <6a4202/figure_2.png>`D and $-\mathrm{E}$ ).
+Apparently, the transition from wax to air into the straight on direction towards R1, as in {numref}`Figure {number} <6a4202_figure_1.png>`C, is a barrier to the microwaves, but not completely (as in {numref}`Figure {number} <6a4202_figure_2.png>`D and $-\mathrm{E}$ ).
Solving the Schroedinger wave equation provides a satisfying solution, because this shows that within a barrier the solution to the wave equation is decaying exponential, dying away to zero, and so, if that barrier ends before this zero is reached, then there is again a sinusoidal wave function. (See the many textbooks on this subject.)
## Remarks
diff --git a/book/book/6 optics/6A geometrical optics/6A60 Thin Lens/6A6001 Chromatic Aberration/6A6001.md b/book/book/6 optics/6A geometrical optics/6A60 Thin Lens/6A6001 Chromatic Aberration/6A6001.md
index e6bc24a7..6757d8fb 100644
--- a/book/book/6 optics/6A geometrical optics/6A60 Thin Lens/6A6001 Chromatic Aberration/6A6001.md
+++ b/book/book/6 optics/6A geometrical optics/6A60 Thin Lens/6A6001 Chromatic Aberration/6A6001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a6001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a6001_figure_0.png
+
.
```
@@ -43,12 +42,11 @@ When the $150 \mathrm{~mm}$ single lens is replaced by the doublet of $150 \math
## Explanation
Since the thin-lens equation $\frac{1}{f}=\left(n_{t}-1\right)\left(\frac{1}{R_{1}}-\frac{1}{R_{2}}\right)$ is wavelength-dependent via $n_{1}(\lambda)$
-(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6a6001/figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a6001/figure_1.png
----
+(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6a6001_figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a6001_figure_1.png
+
.
```
In general $n_{1}(\lambda)$ decreases with wavelength over the visible region, and thus $f(\lambda)$ increases with $\lambda$. And when $f(\lambda)$ increases with $\lambda$, then also the image-distance increases with $\lambda$ (object-distance is constant). The demonstration shows this: the red image being sharp at a larger distance than the blue image.
diff --git a/book/book/6 optics/6A geometrical optics/6A70 Optical Instruments/6A7001 Magnifying Glass/6A7001.md b/book/book/6 optics/6A geometrical optics/6A70 Optical Instruments/6A7001 Magnifying Glass/6A7001.md
index 55d15b1d..4991ae33 100644
--- a/book/book/6 optics/6A geometrical optics/6A70 Optical Instruments/6A7001 Magnifying Glass/6A7001.md
+++ b/book/book/6 optics/6A geometrical optics/6A70 Optical Instruments/6A7001 Magnifying Glass/6A7001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6a7001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6a7001_figure_0.png
+
.
```
@@ -62,15 +61,14 @@ First we use only the "Eye-part" and focus it at an object in the lecture-room f
Notify the results obtained and discuss them.
## Explanation
-When no lens is used, the object is at the near point and observed at an angle $\alpha_{u}$ (see {numref}`Figure {number} <6a7001/figure_1.png>`).
+When no lens is used, the object is at the near point and observed at an angle $\alpha_{u}$ (see {numref}`Figure {number} <6a7001_figure_1.png>`).
+
+When the lens is directly in front of the eye, the image is virtual and erect and must be observed at near point. To have this, the object has to be less than one focal length away from the lens (see {numref}`Figure {number} <6a7001_figure_1.png>`b). Analysis shows that the angular magnification equals $M=\frac{\alpha_{a}}{\alpha_{u}}=\frac{d_{0}}{f}+1$
-When the lens is directly in front of the eye, the image is virtual and erect and must be observed at near point. To have this, the object has to be less than one focal length away from the lens (see {numref}`Figure {number} <6a7001/figure_1.png>`b). Analysis shows that the angular magnification equals $M=\frac{\alpha_{a}}{\alpha_{u}}=\frac{d_{0}}{f}+1$
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6a7001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6a7001/figure_1.png
----
.
```
@@ -80,7 +78,7 @@ $$
M=\frac{\alpha_{a}}{\alpha_{u}}=\frac{d_{0}}{f}
$$
-Still the eye is close to the object. (see {numref}`Figure {number} <6a7001/figure_1.png>`c) (Theoretically a larger distance between magnifying glass and object is possible but then distorsion occurs, since the eyelens sees the imageforming rays no longer paraxial.)
+Still the eye is close to the object. (see {numref}`Figure {number} <6a7001_figure_1.png>`c) (Theoretically a larger distance between magnifying glass and object is possible but then distorsion occurs, since the eyelens sees the imageforming rays no longer paraxial.)
When the object is a comfortable reading distance away analysis shows
@@ -88,7 +86,7 @@ $$
M=\frac{L}{p\left[1+\frac{(f-p) d}{p f}\right]}
$$
-(see {numref}`Figure {number} <6a7001/figure_1.png>`d).
+(see {numref}`Figure {number} <6a7001_figure_1.png>`d).
So for maximum magnification the magnifying glass should be hold closely to the eye. To have a more comfortable situation you have to be content with a lower magnification.
diff --git a/book/book/6 optics/6B photometry/6B30 Radiation Pressure/6B3001 Radiation Pressure/6B3001.md b/book/book/6 optics/6B photometry/6B30 Radiation Pressure/6B3001 Radiation Pressure/6B3001.md
index a7102562..36f53c11 100644
--- a/book/book/6 optics/6B photometry/6B30 Radiation Pressure/6B3001 Radiation Pressure/6B3001.md
+++ b/book/book/6 optics/6B photometry/6B30 Radiation Pressure/6B3001 Radiation Pressure/6B3001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6b3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6b3001_figure_0.png
+
.
```
diff --git a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1001 Resolution/6C1001.md b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1001 Resolution/6C1001.md
index 50330723..c55b270e 100644
--- a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1001 Resolution/6C1001.md
+++ b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1001 Resolution/6C1001.md
@@ -8,18 +8,17 @@
* 6C10 (Diffraction From Two Sources)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c1001_figure_0.png
+
.
```
## Equipment
-- Rotatable disc with 8 holes: $3.0,2.5,2.0,1.5,1.0,0.5,0.4$ and $0.3 \mathrm{~mm}$ (see {numref}`Figure {number} <6c1001/figure_1.png>`).
-- Aluminium foil with 2 pair of holes fitted on a stand (see Diagram and {numref}`Figure {number} <6c1001/figure_2.png>`).
+- Rotatable disc with 8 holes: $3.0,2.5,2.0,1.5,1.0,0.5,0.4$ and $0.3 \mathrm{~mm}$ (see {numref}`Figure {number} <6c1001_figure_1.png>`).
+- Aluminium foil with 2 pair of holes fitted on a stand (see Diagram and {numref}`Figure {number} <6c1001_figure_2.png>`).
- Lamp, 220V/200W.
- Variable transformer on the $220 \mathrm{~V}$ line voltage.
- Camera with zoom lens.
@@ -37,51 +36,47 @@ Built the demonstration as shown in the Diagram:
-The lamp should not be too close to the Aluminum foil, because we need parallel light beams from the holes in the Aluminium foil. To avoid scattered light a cardboard tube is placed between lamp and the Aluminium foil.
-Adjust the vertical and horizontal position of the lamp and also its intensity to get a satisfying illumination of the small holes in the foil.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c1001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c1001_figure_1.png
+
.
```
The lamp is switched on. The rotatable disc has its largest hole in position. The camera is focussed at the pairs of holes in the aluminium foil. The holes of both pairs in the aluminium foil are observed as separate images.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c1001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c1001_figure_2.png
+
.
```
### Presentation
Choose the smallest hole in the rotatable disc. Two rather hazy patches of light are observed by the camera. One of the two patches gives the idea that it could be a double spot. Then a larger hole is selected on the rotatable disc and we see that our idea of one of the light patches being two separate spots is strengthened.
-When we continue to select larger holes on the rotatable disc the light spot resolves as really consisting of two light spots. Even the other light spot finally resolves into two! {numref}`Figure {number} <6c1001/figure_3.png>` shows the sequence of the observed light spots.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6c1001/figure_3.png
----
+When we continue to select larger holes on the rotatable disc the light spot resolves as really consisting of two light spots. Even the other light spot finally resolves into two! {numref}`Figure {number} <6c1001_figure_3.png>` shows the sequence of the observed light spots.
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6c1001_figure_3.png
+
.
```
(In demonstrating we also go again backwards to smaller holes in the diaphragm.)
## Explanation
-If two point objects are very close, the diffraction patterns of their images will overlap. As the objects are moved closer, a separation is reached where you can't tell if there are two overlapping images or a single image. The separation at which this happens is stated by Lord Rayleigh: two images are just resolvable when the centre of the diffraction disk of one image is directly over the first minimum in the diffraction disc of the other. A circular hole shows a diffraction pattern with a central maximum of half width: $\theta=\frac{1.22 \lambda}{D}$, where $D$ is the diameter of the circular opening. Calculating with $\lambda=500 \mathrm{~nm}$ we get for the smallest hole on the rotatable disc $D=.3 \mathrm{~mm}, \theta=2 \times 10^{-3}$.
+If two point objects are very close, the diffraction patterns of their images will overlap. As the objects are moved closer, a separation is reached where you can't tell if there are two overlapping images or a single image. The separation at which this happens is stated by Lord Rayleigh: two images are just resolvable when the centre of the diffraction disk of one image is directly over the first minimum in the diffraction disc of the other. A circular hole shows a diffraction pattern with a central maximum of half :width: $\theta=\frac{1.22 \lambda}{D}$, where $D$ is the diameter of the circular opening. Calculating with $\lambda=500 \mathrm{~nm}$ we get for the smallest hole on the rotatable disc $D=.3 \mathrm{~mm}, \theta=2 \times 10^{-3}$.
+
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 6c1001_figure_4.png
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 6c1001/figure_4.png
----
.
```
-In our demonstration: $\theta=\frac{\Delta l}{f}$ (see {numref}`Figure {number} <6c1001/figure_4.png>`).
+In our demonstration: $\theta=\frac{\Delta l}{f}$ (see {numref}`Figure {number} <6c1001_figure_4.png>`).
The distance $f=2$ meter, and calculating $\theta$ for both pair of holes, we get $\theta=.75 \times 10^{-3}$ for the pair of holes with a separation of $1.5 \mathrm{~mm}$ and $\theta=2 \times 10^{-3}$ for the pair of holes with a separation of 4 $\mathrm{mm}$.
-These calculations compared with the Rayleigh criterion (that is expressed as $\theta=\frac{1.22 \lambda}{D}$ and is calculated and listed in the bottom row of {numref}`Figure {number} <6c1001/figure_3.png>`), shows that the two holes with a separation of $4 \mathrm{~mm}$ will be resolved when the diaphragm is larger than $.3 \mathrm{~mm}$ and that the holes with a separation of $1.5 \mathrm{~mm}$ will be resolved when the diaphragm is larger than $.5 \mathrm{~mm}$. The observed light spots in {numref}`Figure {number} <6c1001/figure_3.png>` show that this is more or less right!
+These calculations compared with the Rayleigh criterion (that is expressed as $\theta=\frac{1.22 \lambda}{D}$ and is calculated and listed in the bottom row of {numref}`Figure {number} <6c1001_figure_3.png>`), shows that the two holes with a separation of $4 \mathrm{~mm}$ will be resolved when the diaphragm is larger than $.3 \mathrm{~mm}$ and that the holes with a separation of $1.5 \mathrm{~mm}$ will be resolved when the diaphragm is larger than $.5 \mathrm{~mm}$. The observed light spots in {numref}`Figure {number} <6c1001_figure_3.png>` show that this is more or less right!
## Remarks
Since $\theta=\frac{1.22 \lambda}{D}$, it is useful to do this demonstration in different colours. (We didn't try this yet.)
diff --git a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1002 Fraunhofer and Fresnel Diffraction/6C1002.md b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1002 Fraunhofer and Fresnel Diffraction/6C1002.md
index a450d574..eba0e219 100644
--- a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1002 Fraunhofer and Fresnel Diffraction/6C1002.md
+++ b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1002 Fraunhofer and Fresnel Diffraction/6C1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c1002_figure_0.png
+
.
```
@@ -46,16 +45,15 @@ The demonstration is set up as shown in Diagram:
### Demonstration
-The set-up as described in "Preparation" is explained to the students, so that it is clear to them that the adjustable slit is placed in a beam of light consisting of parallel rays. The adjustable slit is set at $.6 \mathrm{~mm}$. The $+132 \mathrm{~mm}$ lens is shifted close to this slit to project a sharp image of it on the wall: a smooth red region, having a sharp boundary on both sides (see {numref}`Figure {number} <6c1002/figure_1.png>`A). Considering the wall to be far away, the lens needs to be $+132 \mathrm{~mm}$ away from the slit (the slit is in the focus of the projecting lens).
+The set-up as described in "Preparation" is explained to the students, so that it is clear to them that the adjustable slit is placed in a beam of light consisting of parallel rays. The adjustable slit is set at $.6 \mathrm{~mm}$. The $+132 \mathrm{~mm}$ lens is shifted close to this slit to project a sharp image of it on the wall: a smooth red region, having a sharp boundary on both sides (see {numref}`Figure {number} <6c1002_figure_1.png>`A). Considering the wall to be far away, the lens needs to be $+132 \mathrm{~mm}$ away from the slit (the slit is in the focus of the projecting lens).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c1002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c1002/figure_1.png
----
.
```
-Then the $+132 \mathrm{~mm}$ lens is slowly shifted away from the slit. The projected image changes: in the originally smooth red region domains of higher and lower intensity (fringes) can be discerned (see {numref}`Figure {number} <6c1002/figure_1.png>`B). Moving out still farther, the fringe pattern changes continuously: the number of fringes diminishes while the fringes themselves broaden (compare the pictures in {numref}`Figure {number} <6c1002/figure_1.png>`; reality is better than the quality of these pictures). When the $+132 \mathrm{~mm}$ lens has reached the end of the guidance rail the familiar diffraction pattern as shown when introducing diffraction, is visible (see the demonstration ["Diffraction(2), single slit"](<../../6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md>)).
+Then the $+132 \mathrm{~mm}$ lens is slowly shifted away from the slit. The projected image changes: in the originally smooth red region domains of higher and lower intensity (fringes) can be discerned (see {numref}`Figure {number} <6c1002_figure_1.png>`B). Moving out still farther, the fringe pattern changes continuously: the number of fringes diminishes while the fringes themselves broaden (compare the pictures in {numref}`Figure {number} <6c1002_figure_1.png>`; reality is better than the quality of these pictures). When the $+132 \mathrm{~mm}$ lens has reached the end of the guidance rail the familiar diffraction pattern as shown when introducing diffraction, is visible (see the demonstration ["Diffraction(2), single slit"](<../../6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md>)).
Leaving the $+132 \mathrm{~mm}$ lens in this far away position, the transformation from Fresnel to Fraunhofer can also be shown when you vary the width of the slit.
@@ -63,14 +61,13 @@ It will be clear now that distance form the slit and slit-width have both someth
## Explanation
The $+132 \mathrm{~mm}$ lens being for away from the wall projects an image of an "object" that is $132 \mathrm{~mm}$ away form it. At first we seen the sharply imaged slit; moving away from the slit, for instance $10 \mathrm{~mm}$, then the image of this position is projected on the wall. In this way the lens scans the region close to the slit (near field) and farther away (far field). Considering far field diffraction (Fraunhofer diffraction) the slit is that narrow compared to the distance in the field, that the secondary wavelets emerging from the slit proceed as being planar. This relative simplicity of Fraunhofer diffraction is explained in the demonstration "Diffraction(2), single slit" in this database.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c1002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c1002_figure_2.png
+
.
```
-In the near field configuration the width of the slit cannot longer be neglected. Due to this an extra path difference (PQ) between ray 1 and ray 2 is introduced (see {numref}`Figure {number} <6c1002/figure_2.png>`).
+In the near field configuration the width of the slit cannot longer be neglected. Due to this an extra path difference (PQ) between ray 1 and ray 2 is introduced (see {numref}`Figure {number} <6c1002_figure_2.png>`).
Applying Pythagoras shows $L^{2}+\frac{a^{2}}{4}=(L+P Q)^{2}$, and $P Q=\frac{a^{2}}{8 L}$. If, as a rule of thumb, this extra path difference is neglected if it is smaller than $\lambda / 4$, we find that for the distance $L$ we need $L>\frac{a^{2}}{2 \lambda}$. So, the distance $L \approx \frac{a^{2}}{2 \lambda}$ can be considered as the "border" between Fresnel - and Fraunhofer diffraction. Applying the data In this demonstration $(a=.6 \mathrm{~mm} ; \lambda=650 \mathrm{~nm})$, we find: $L=.25 \mathrm{~m}$. Performing the demonstration confirms this.
diff --git a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1003 Youngs Double Slit/6C1003.md b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1003 Youngs Double Slit/6C1003.md
index 14379d1e..41abe67c 100644
--- a/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1003 Youngs Double Slit/6C1003.md
+++ b/book/book/6 optics/6C diffraction/6C10 Diffraction From Two Sources/6C1003 Youngs Double Slit/6C1003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c1003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c1003_figure_0.png
+
.
```
@@ -53,24 +52,22 @@ The set-up as described in Preparation is shortly explained to the students. The
The slide with the double slits is placed on an overhead projector, so the students can see the configuration. The dimensions are indicated on an overhead sheet that is projected at the same time.
-The laser is switched on, the broadened beam projects on the wall. When the $+132 \mathrm{~mm}$ lens is placed at the end of the table, this spot is enlarged (see {numref}`Figure {number} <6c1003/figure_1.png>`A; the diameter of the projected spot is around $1 \mathrm{~m}$ ). Then the double slit is shifted into the beam starting with configuration a (see Equipment).
+The laser is switched on, the broadened beam projects on the wall. When the $+132 \mathrm{~mm}$ lens is placed at the end of the table, this spot is enlarged (see {numref}`Figure {number} <6c1003_figure_1.png>`A; the diameter of the projected spot is around $1 \mathrm{~m}$ ). Then the double slit is shifted into the beam starting with configuration a (see Equipment).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c1003_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c1003/figure_1.png
----
.
```
-The typical interference pattern appears (see {numref}`Figure {number} <6c1003/figure_1.png>`B; {numref}`Figure {number} <6c1003/figure_1.png>`C shows a snapshot of a real projection on the wall). Then we shift to configuration $\mathbf{b}$, then $\mathbf{b}$ and finally $\mathbf{b}$; in that way going from large to smaller slit-separation. It is observed that with smaller slitseparation the distance between the lines of interference increases
+The typical interference pattern appears (see {numref}`Figure {number} <6c1003_figure_1.png>`B; {numref}`Figure {number} <6c1003_figure_1.png>`C shows a snapshot of a real projection on the wall). Then we shift to configuration $\mathbf{b}$, then $\mathbf{b}$ and finally $\mathbf{b}$; in that way going from large to smaller slit-separation. It is observed that with smaller slitseparation the distance between the lines of interference increases
## Explanation
-Young explained the observed pattern with the Huygens wave theory and so introduced the principle of interference. Many textbooks give the explanation. {numref}`Figure {number} <6c1003/figure_2.png>` shows the arrangement: $s$ is very large compared to the slit separation $b$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c1003/figure_2.png
----
+Young explained the observed pattern with the Huygens wave theory and so introduced the principle of interference. Many textbooks give the explanation. {numref}`Figure {number} <6c1003_figure_2.png>` shows the arrangement: $s$ is very large compared to the slit separation $b$.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c1003_figure_2.png
+
.
```
In $P$, ray $r_{1}$ and ray $r_{2}$ interfere. This interference will be constructive when $r_{1}-r_{2}=m \lambda$ $(m=0,1,2,3, \ldots)$.
diff --git a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2001 Diffraction introduction/6C2001.md b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2001 Diffraction introduction/6C2001.md
index 287e6197..2b54d3c2 100644
--- a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2001 Diffraction introduction/6C2001.md
+++ b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2001 Diffraction introduction/6C2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c2001_figure_0.png
+
.
```
@@ -58,31 +57,28 @@ The set-up as described in Preparation is shortly explained to the students. The
The razorblade is placed on an overhead projector, so the students can see its shape. The laser is switched on and the broadened beam projects on the wall (see Diagram, $\mathrm{C}_{1}$; the diameter of the projected spot is around $1 \mathrm{~m}$ ). Then the razorblade is shifted on the slide holder into the beam. The typical diffraction pattern appears (see Diagram, $\mathrm{C}_{2}$ ). This photograph is of a poor quality as compared to what we see in the projection: we easily see around 10 fringes. The razorblade is removed and the demonstrator holds his fingertip in the broadened beam. Also now a fringed shadow pattern appears. Then the razorblade is set vertically in the slide holder and the shadow of one side of the razorblade is observed more carefully: We see many fringes in the region of uniform illumination. The distance between the fringes diminishes as we move away from the geometrical shadow line. Also very clear is that the intensity of the first fringe is higher then the intensity of the uniform illumination.
###optional
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c2001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c2001_figure_1.png
+
.
```
- The pattern scanner, as described in the list of equipment,is placed in the projected beam (see {numref}`Figure {number} <6c2001/figure_1.png>`) and connected to the interface to scan and record position and intensity of the image on the pc. First the intensity of the broadened laserbeam is registered (see {numref}`Figure {number} <6c2001/figure_2.png>`, red line). Then the razorblade is positioned vertically, blocking half the beam and again the whole pattern is scanned (see {numref}`Figure {number} <6c2001/figure_2.png>`, green line).
+ The pattern scanner, as described in the list of equipment,is placed in the projected beam (see {numref}`Figure {number} <6c2001_figure_1.png>`) and connected to the interface to scan and record position and intensity of the image on the pc. First the intensity of the broadened laserbeam is registered (see {numref}`Figure {number} <6c2001_figure_2.png>`, red line). Then the razorblade is positioned vertically, blocking half the beam and again the whole pattern is scanned (see {numref}`Figure {number} <6c2001_figure_2.png>`, green line).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c2001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c2001/figure_2.png
----
.
```
In this registration it is very clear that there is an increase and decrease all over the fringe pattern (by eye we see only the increase in intensity of the first fringe). When the fringe pattern is enlarged, the continuing fringing can be seen at all points of the registered intensity. Also the change in fringe separation is very clear. We also see that in the shadow region the intensity drops off rapidly.
## Explanation
The first part of the demonstration is used as an introduction to diffraction, to give some idea of the richness and complexity of "just casting a shadow by an opaque object". The second part of the demonstration shows that in the shadow image there are points of constructive - and destructive interference. An extensive explanation of the fringed pattern is not appropriate when this demonstration is used just as an introduction to diffraction.(Such an explanation needs Fresnel equations and the visualization by means of the Cornu spiral.) At such an introductory stage it suffices to look at Figure3, where the secondary wavelets emitting from the red points (Huygens-Fresnel principle) next to the edge of the razorblade meet at $P$.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6c20.01/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6c20.01_figure_3.png
+
.
```
diff --git a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md
index e9d4ae69..6e46e6be 100644
--- a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md
+++ b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/6C2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c2002_figure_0.png
+
.
```
@@ -29,17 +28,8 @@ name: 6c2002/figure_0.png
## Presentation
-
-
-
-
-
+```{iframe} https://www.youtube.com/embed/yTNxj_2iOc4?si=FT1tVAM85De71-Lu
+```
### Preparation
diff --git a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/qr_images/qrcode_yTNxj_2iOc4_si_FT1tVAM85De71_Lu_.svg b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/qr_images/qrcode_yTNxj_2iOc4_si_FT1tVAM85De71_Lu_.svg
new file mode 100644
index 00000000..c137dbb0
--- /dev/null
+++ b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2002 Diffraction Single Slit/qr_images/qrcode_yTNxj_2iOc4_si_FT1tVAM85De71_Lu_.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2003 Diffraction Single Slit/6C2003.md b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2003 Diffraction Single Slit/6C2003.md
index 108c6223..b3c81841 100644
--- a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2003 Diffraction Single Slit/6C2003.md
+++ b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2003 Diffraction Single Slit/6C2003.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c2003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c2003_figure_0.png
+
.
```
@@ -28,7 +27,7 @@ name: 6c2003/figure_0.png
- Lens, $\mathrm{f}=132 \mathrm{~mm}$.
- Opticail rail, $\mathrm{I}=1 \mathrm{~m}$, as guiding ruler.
- Variable slit with vernier adjustment.
-- Overheadsheet with {numref}`Figure {number} <6c2003/figure_1.png>`.
+- Overheadsheet with {numref}`Figure {number} <6c2003_figure_1.png>`.
## Presentation
@@ -44,12 +43,11 @@ The demonstration is set up as shown in Diagram:
The set-up as described in Preparation is shortly explained to the students. The most important in this explanation is that the slit will be placed in a broadened beam and that the adjustable slit will be illuminated by plane waves.
-The laser is switched on. A spot of $2 \mathrm{~cm}$ projects on the wall (see ["Diffraction(2a)](../6C2002 Diffraction Single Slit/6C2002.md>)). The $+132 \mathrm{~mm}$-lens is placed at the end of the guiding ruler, to project an enlarged image of the interference-pattern as it will be "seen" around $85 \mathrm{~cm}$ (1m-132mm) behind the slit. The broadened and enlarged beam projects as a spot on the wall (diameter of the spot is around $40 \mathrm{~cm}$ ). The slit is closed and positioned in the beam. (By means of an overheadsheet it is shown to the students what the geometrical projection will show to us (see {numref}`Figure {number} <6c2003/figure_1.png>`): When the wall is at a distance as indicated in this figure, then the slit width $a$ is projected 20 times larger on the wall. So when the slit width is $0,1 \mathrm{~mm}$, then we will see a width of $2 \mathrm{~mm}$.)
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c2003/figure_1.png
----
+The laser is switched on. A spot of $2 \mathrm{~cm}$ projects on the wall (see ["Diffraction(2a)](../6C2002 Diffraction Single Slit/6C2002.md>)). The $+132 \mathrm{~mm}$-lens is placed at the end of the guiding ruler, to project an enlarged image of the interference-pattern as it will be "seen" around $85 \mathrm{~cm}$ (1m-132mm) behind the slit. The broadened and enlarged beam projects as a spot on the wall (diameter of the spot is around $40 \mathrm{~cm}$ ). The slit is closed and positioned in the beam. (By means of an overheadsheet it is shown to the students what the geometrical projection will show to us (see {numref}`Figure {number} <6c2003_figure_1.png>`): When the wall is at a distance as indicated in this figure, then the slit width $a$ is projected 20 times larger on the wall. So when the slit width is $0,1 \mathrm{~mm}$, then we will see a width of $2 \mathrm{~mm}$.)
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c2003_figure_1.png
+
.
```
-slit at $0.2 \mathrm{~mm}$, band of light $=15 \mathrm{~cm}$, first subsidiary maxima appear;
@@ -65,15 +63,14 @@ At this $0.7 \mathrm{~mm}$ slit width the first subsidiary maxima are almost as
## Explanation
When the slit is $0.1 \mathrm{~mm}$ and the geometrical projection would be only $2 \mathrm{~mm}$ wide, clearly light is bending, broadening the band to $20 \mathrm{~cm}$.
-Many textbooks give a detailed explanation (see Sources). We consider {numref}`Figure {number} <6c2003/figure_2.png>`.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c2003/figure_2.png
----
+Many textbooks give a detailed explanation (see Sources). We consider {numref}`Figure {number} <6c2003_figure_2.png>`.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c2003_figure_2.png
+
.
```
-At $\mathrm{P}, \mathrm{N}$ secondary wavelets superimpose, having a path difference of $\frac{a}{N} \sin \theta$. Applying phase addition (see {numref}`Figure {number} <6c2003/figure_2.png>`B), $\mathrm{A}_{p}$ is the resultant wave amplitude at $\mathrm{P}$. At $\mathrm{O}$, the total amplitude of the secondary wavelets will be the arclength in that phasor diagram, since all vectors then have the same phase. At Q ( $\theta$ is larger) the phase difference between the "individual" secondary wavelets is larger and the phase diagram ({numref}`Figure {number} <6c2003/figure_2.png>`C) shows that the total amplitude can eventually be zero.
+At $\mathrm{P}, \mathrm{N}$ secondary wavelets superimpose, having a path difference of $\frac{a}{N} \sin \theta$. Applying phase addition (see {numref}`Figure {number} <6c2003_figure_2.png>`B), $\mathrm{A}_{p}$ is the resultant wave amplitude at $\mathrm{P}$. At $\mathrm{O}$, the total amplitude of the secondary wavelets will be the arclength in that phasor diagram, since all vectors then have the same phase. At Q ( $\theta$ is larger) the phase difference between the "individual" secondary wavelets is larger and the phase diagram ({numref}`Figure {number} <6c2003_figure_2.png>`C) shows that the total amplitude can eventually be zero.
Analysis gives for the intensities $\left(I_{\theta}\right)$ (see textbooks): $\frac{I_{\theta}}{I_{0}}=\left[\frac{\sin \left(\frac{\pi a \sin \theta}{\lambda}\right)}{\frac{\pi a \sin \theta}{\lambda}}\right]^{2}=\left[\frac{\sin \alpha}{\alpha}\right]$. Minima occur at $\sin \alpha=0$, so when $\alpha=\mathrm{n} \pi$, and maxima at $\alpha=\left(\frac{2 n+1}{2}\right) \pi$. The intensities of these maxima are then given by $\frac{I_{\theta}}{I_{0}}=\frac{\sin ^{2} \alpha}{\alpha}=\frac{4}{(2 n+1)^{2} \pi^{2}}$.
@@ -84,7 +81,7 @@ $\mathrm{n}=2, \mathrm{I}_{2}=0.016 \mathrm{I}_{0}$, etc.
So, the subsidiary maxima are comparatively weak, but yet clearly visible as the demonstration showed.
## Remarks
-- The $+132 \mathrm{~mm}$ lens is positioned at a distance of about $1 \mathrm{~m}$ away from the slit. This means that on the wall an image is projected of a point around $85 \mathrm{~cm}$ (1m-132mm) away from that slit. In that way it is assured that the diffraction pattern is far field Fraunhofer pattern. Increasing the slit opening beyond $0.7 \mathrm{~mm}$ will transfer the projected pattern into a Fresnel diffraction pattern, spoiling (complicating) our demonstration. The transition form Fraunhofer to Fresnel diffraction occurs in this set-up at around (see {numref}`Figure {number} <6c2003/figure_1.png>`): $s=a^{2} / 2 \lambda, s=85 \mathrm{~cm}$, so $a=1 \mathrm{~mm}$. In this single slit introductory demonstration we should not go beyond that width. (See the demonstration ["Fraunhofer-Fresneldiffraction"](<../6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md>).)
+- The $+132 \mathrm{~mm}$ lens is positioned at a distance of about $1 \mathrm{~m}$ away from the slit. This means that on the wall an image is projected of a point around $85 \mathrm{~cm}$ (1m-132mm) away from that slit. In that way it is assured that the diffraction pattern is far field Fraunhofer pattern. Increasing the slit opening beyond $0.7 \mathrm{~mm}$ will transfer the projected pattern into a Fresnel diffraction pattern, spoiling (complicating) our demonstration. The transition form Fraunhofer to Fresnel diffraction occurs in this set-up at around (see {numref}`Figure {number} <6c2003_figure_1.png>`): $s=a^{2} / 2 \lambda, s=85 \mathrm{~cm}$, so $a=1 \mathrm{~mm}$. In this single slit introductory demonstration we should not go beyond that width. (See the demonstration ["Fraunhofer-Fresneldiffraction"](<../6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md>).)
## Sources
- Hecht, Eugene, Optics, pag. 442-447
diff --git a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md
index 06fb512f..751ea504 100644
--- a/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md
+++ b/book/book/6 optics/6C diffraction/6C20 Diffraction Around Objects/6C2004 Fraunhofer and Fresnel Diffraction/6C2004.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6c2004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6c2004_figure_0.png
+
.
```
@@ -46,16 +45,15 @@ The demonstration is set up as shown in Diagram:
### Demonstration
-The set-up as described in "Preparation" is explained to the students, so that it is clear to them that the adjustable slit is placed in a beam of light consisting of parallel rays. The adjustable slit is set at $.6 \mathrm{~mm}$. The $+132 \mathrm{~mm}$ lens is shifted close to this slit to project a sharp image of it on the wall: a smooth red region, having a sharp boundary on both sides (see {numref}`Figure {number} <6c2004/figure_1.png>`A). Considering the wall to be far away, the lens needs to be $+132 \mathrm{~mm}$ away from the slit (the slit is in the focus of the projecting lens).
+The set-up as described in "Preparation" is explained to the students, so that it is clear to them that the adjustable slit is placed in a beam of light consisting of parallel rays. The adjustable slit is set at $.6 \mathrm{~mm}$. The $+132 \mathrm{~mm}$ lens is shifted close to this slit to project a sharp image of it on the wall: a smooth red region, having a sharp boundary on both sides (see {numref}`Figure {number} <6c2004_figure_1.png>`A). Considering the wall to be far away, the lens needs to be $+132 \mathrm{~mm}$ away from the slit (the slit is in the focus of the projecting lens).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6c2004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6c2004/figure_1.png
----
.
```
-Then the $+132 \mathrm{~mm}$ lens is slowly shifted away from the slit. The projected image changes: in the originally smooth red region domains of higher and lower intensity (fringes) can be discerned (see {numref}`Figure {number} <6c2004/figure_1.png>`B). Moving out still farther, the fringe pattern changes continuously: the number of fringes diminishes while the fringes themselves broaden (compare the pictures in {numref}`Figure {number} <6c2004/figure_1.png>`; reality is better than the quality of these pictures). When the $+132 \mathrm{~mm}$ lens has reached the end of the guidance rail the familiar diffraction pattern as shown when introducing diffraction, is visible (see the demonstration ["Diffraction(2), single slit"](/book/6%20optics/6C%20diffraction/6C20%20Diffraction%20Around%20Objects/6C2002%20Diffraction%20Single%20Slit/6C2002.md).
+Then the $+132 \mathrm{~mm}$ lens is slowly shifted away from the slit. The projected image changes: in the originally smooth red region domains of higher and lower intensity (fringes) can be discerned (see {numref}`Figure {number} <6c2004_figure_1.png>`B). Moving out still farther, the fringe pattern changes continuously: the number of fringes diminishes while the fringes themselves broaden (compare the pictures in {numref}`Figure {number} <6c2004_figure_1.png>`; reality is better than the quality of these pictures). When the $+132 \mathrm{~mm}$ lens has reached the end of the guidance rail the familiar diffraction pattern as shown when introducing diffraction, is visible (see the demonstration ["Diffraction(2), single slit"](/book/6%20optics/6C%20diffraction/6C20%20Diffraction%20Around%20Objects/6C2002%20Diffraction%20Single%20Slit/6C2002.md).
Leaving the $+132 \mathrm{~mm}$ lens in this far away position, the transformation from Fresnel to Fraunhofer can also be shown when you vary the width of the slit.
@@ -63,14 +61,13 @@ It will be clear now that distance form the slit and slit-width have both someth
## Explanation
The $+132 \mathrm{~mm}$ lens being for away from the wall projects an image of an "object" that is $132 \mathrm{~mm}$ away form it. At first we seen the sharply imaged slit; moving away from the slit, for instance $10 \mathrm{~mm}$, then the image of this position is projected on the wall. In this way the lens scans the region close to the slit (near field) and farther away (far field). Considering far field diffraction (Fraunhofer diffraction) the slit is that narrow compared to the distance in the field, that the secondary wavelets emerging from the slit proceed as being planar. This relative simplicity of Fraunhofer diffraction is explained in the demonstration "Diffraction(2), single slit" in this database.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6c2004/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6c2004_figure_2.png
+
.
```
-In the near field configuration the width of the slit cannot longer be neglected. Due to this an extra path difference (PQ) between ray 1 and ray 2 is introduced (see {numref}`Figure {number} <6c2004/figure_2.png>`).
+In the near field configuration the width of the slit cannot longer be neglected. Due to this an extra path difference (PQ) between ray 1 and ray 2 is introduced (see {numref}`Figure {number} <6c2004_figure_2.png>`).
Applying Pythagoras shows $L^{2}+\frac{a^{2}}{4}=(L+P Q)^{2}$, and $P Q=\frac{a^{2}}{8 L}$. If, as a rule of thumb, this extra path difference is neglected if it is smaller than $\lambda / 4$, we find that for the distance $L$ we need $L>\frac{a^{2}}{2 \lambda}$. So, the distance $L \approx \frac{a^{2}}{2 \lambda}$ can be considered as the "border" between Fresnel - and Fraunhofer diffraction. Applying the data In this demonstration $(a=.6 \mathrm{~mm} ; \lambda=650 \mathrm{~nm})$, we find: $L=.25 \mathrm{~m}$. Performing the demonstration confirms this.
diff --git a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1001 Fresnel Double Mirror/6D1001.md b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1001 Fresnel Double Mirror/6D1001.md
index 3a51da54..66e21ee9 100644
--- a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1001 Fresnel Double Mirror/6D1001.md
+++ b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1001 Fresnel Double Mirror/6D1001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d1001_figure_0.png
+
.
```
@@ -28,34 +27,31 @@ name: 6d1001/figure_0.png
## Presentation
-The room is darkened and the laser is switched on. By means of the $+20 \mathrm{~mm}$ lens an illuminated disk is projected on the white screen. The Fresnel double mirror is adjusted so that the two halves of the mirror are parallel. The mirror surface is shifted into the diverging light beam, approximately parallel to it and turned just that much so that the beam of rays strike both mirror halves equally. Two light spots (half circles) are visible on the screen/monitor, separated by a dark zone (see {numref}`Figure {number} <6d1001/figure_1.png>`).
+The room is darkened and the laser is switched on. By means of the $+20 \mathrm{~mm}$ lens an illuminated disk is projected on the white screen. The Fresnel double mirror is adjusted so that the two halves of the mirror are parallel. The mirror surface is shifted into the diverging light beam, approximately parallel to it and turned just that much so that the beam of rays strike both mirror halves equally. Two light spots (half circles) are visible on the screen/monitor, separated by a dark zone (see {numref}`Figure {number} <6d1001_figure_1.png>`).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d1001_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d1001/figure_1.png
----
.
```
-Turning the adjustment screw of the Fresnel mirror, the movable part of the mirror is tilted and the two light spots start overlapping. From a distance, an intensification of the light in the overlapping zone is clearly observed. Then, at a closer look, by means of a camera, a clear interference pattern is observed. (see {numref}`Figure {number} <6d1001/figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d1001/figure_2.png
----
+Turning the adjustment screw of the Fresnel mirror, the movable part of the mirror is tilted and the two light spots start overlapping. From a distance, an intensification of the light in the overlapping zone is clearly observed. Then, at a closer look, by means of a camera, a clear interference pattern is observed. (see {numref}`Figure {number} <6d1001_figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d1001_figure_2.png
+
.
```
Stress especially the clearly visible increase in intensity of the fringes themselves and the zero intensity between them, illustrating respectively the constructive - and destructive interference. The separation between the fringes becomes less the more the movable mirror is pivoted.
## Explanation
-One part of the wavefront coming from point $S$ is reflected from the first mirror and the other part is reflected from the second mirror (see {numref}`Figure {number} <6d1001/figure_3.png>`).
+One part of the wavefront coming from point $S$ is reflected from the first mirror and the other part is reflected from the second mirror (see {numref}`Figure {number} <6d1001_figure_3.png>`).
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6d1001_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6d1001/figure_3.png
----
.
```
An interference field exists in the region where the two reflected waves are superimposed. The mirror images $S_{1}$ and $S_{2}$ can be considered as separate coherent sources, placed a distance $a$ apart. The separation ( $\Delta y$ ) between the fringes is given by $\Delta y \approx \frac{s}{a} \lambda$ ( $s$ being the distance between the plane of the two sources and the screen).
diff --git a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1002 Fresnel Double Prism/6D1002.md b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1002 Fresnel Double Prism/6D1002.md
index 57ff21e3..39d805a3 100644
--- a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1002 Fresnel Double Prism/6D1002.md
+++ b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1002 Fresnel Double Prism/6D1002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d1002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d1002_figure_0.png
+
.
```
@@ -35,31 +34,28 @@ The laserbeam is switched on and expanded using a telescope consisting of the mi
### Presentation
On the viewing screen, a couple of meters away we see a large circular light spot. (Blowing smoke into the lens set-up enlightens the light path).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d1002/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d1002_figure_1.png
+
.
```
-When descending the biprism (apex line vertical) into the diverging beam, close to the focal point (see {numref}`Figure {number} <6d1002/figure_1.png>`), we see that the original circular light spot is refracted into two half circle segments and that in the centre these two halves overlap (see {numref}`Figure {number} <6d1002/figure_2.png>`), narrowing the original lightspot.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d1002/figure_2.png
----
+When descending the biprism (apex line vertical) into the diverging beam, close to the focal point (see {numref}`Figure {number} <6d1002_figure_1.png>`), we see that the original circular light spot is refracted into two half circle segments and that in the centre these two halves overlap (see {numref}`Figure {number} <6d1002_figure_2.png>`), narrowing the original lightspot.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d1002_figure_2.png
+
.
```
The centre shows an increase in light intensity. When the biprism is moved closer to the focal point of the $50 \mathrm{~mm}$ lens, we will easily see that the centre contains fringes, lines of positive and negative interference. When the biprism is close to this focal point the fringe spacing is large; when the biprism is moving away from the focal point, the fringe spacing is smaller but can still be observed when the viewing screen is tilted.
## Explanation
- See {numref}`Figure {number} <6d1002/figure_3.png>`. The left portion of the wavefront is refracted to the right, the right portion to the left. In the region of superposition interference occurs.
+ See {numref}`Figure {number} <6d1002_figure_3.png>`. The left portion of the wavefront is refracted to the right, the right portion to the left. In the region of superposition interference occurs.
+
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6d1002_figure_3.png
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6d1002/figure_3.png
----
.
```
diff --git a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1003 Lloyds Mirror/6D1003.md b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1003 Lloyds Mirror/6D1003.md
index d416b9b7..52988a62 100644
--- a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1003 Lloyds Mirror/6D1003.md
+++ b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1003 Lloyds Mirror/6D1003.md
@@ -17,25 +17,23 @@
## Presentation
-The room is darkened and the laser is switched on. By means of the $+10 \mathrm{~mm}$-lens an illuminated disk is projected on the white screen. The surface mirror is placed parallel to the diverging light beam (see {numref}`Figure {number} <6d1003/figure_0.png>`A)
+The room is darkened and the laser is switched on. By means of the $+10 \mathrm{~mm}$-lens an illuminated disk is projected on the white screen. The surface mirror is placed parallel to the diverging light beam (see {numref}`Figure {number} <6d1003_figure_0.png>`A)
+
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d1003_figure_0.png
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d1003/figure_0.png
----
.
```
-and then turned just a little, so that the outer rays of the beam are reflected (see {numref}`Figure {number} <6d1003/figure_0.png>`B). In the light spot on the wall the fringes are visible now.
+and then turned just a little, so that the outer rays of the beam are reflected (see {numref}`Figure {number} <6d1003_figure_0.png>`B). In the light spot on the wall the fringes are visible now.
## Explanation
- A portion of the wavefront is reflected from S (see {numref}`Figure {number} <6d1003/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d1003/figure_1.png
----
+ A portion of the wavefront is reflected from S (see {numref}`Figure {number} <6d1003_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d1003_figure_1.png
+
.
```
The other portion proceeds directly to the screen. Interference occurs in the region where the two portions are superimposed $S$ and its mirrorimage $S_{1}$ can be considered as separate coherent sources, placed a distance $a$ apart. Then the separation ( $\Delta y$ ) between the fringes is given by $\Delta y \approx \frac{S}{a} \lambda$ ( $s$ being the distance between the plane of the two sources and the screen).
diff --git a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/6D1004.md b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/6D1004.md
index af52289c..cf124a79 100644
--- a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/6D1004.md
+++ b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/6D1004.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d1004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d1004_figure_0.png
+
.
```
@@ -53,24 +52,22 @@ The set-up as described in Preparation is shortly explained to the students. The
The slide with the double slits is placed on an overhead projector, so the students can see the configuration. The dimensions are indicated on an overhead sheet that is projected at the same time.
-The laser is switched on, the broadened beam projects on the wall. When the $+132 \mathrm{~mm}$ lens is placed at the end of the table, this spot is enlarged (see {numref}`Figure {number} <6d1004/figure_1.png>`A; the diameter of the projected spot is around $1 \mathrm{~m}$ ). Then the double slit is shifted into the beam starting with configuration a (see Equipment).
+The laser is switched on, the broadened beam projects on the wall. When the $+132 \mathrm{~mm}$ lens is placed at the end of the table, this spot is enlarged (see {numref}`Figure {number} <6d1004_figure_1.png>`A; the diameter of the projected spot is around $1 \mathrm{~m}$ ). Then the double slit is shifted into the beam starting with configuration a (see Equipment).
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d1004_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d1004/figure_1.png
----
.
```
-The typical interference pattern appears (see {numref}`Figure {number} <6d1004/figure_1.png>`B; {numref}`Figure {number} <6d1004/figure_1.png>`C shows a snapshot of a real projection on the wall). Then we shift to configuration $\mathbf{b}$, then $\mathbf{b}$ and finally $\mathbf{b}$; in that way going from large to smaller slit-separation. It is observed that with smaller slitseparation the distance between the lines of interference increases
+The typical interference pattern appears (see {numref}`Figure {number} <6d1004_figure_1.png>`B; {numref}`Figure {number} <6d1004_figure_1.png>`C shows a snapshot of a real projection on the wall). Then we shift to configuration $\mathbf{b}$, then $\mathbf{b}$ and finally $\mathbf{b}$; in that way going from large to smaller slit-separation. It is observed that with smaller slitseparation the distance between the lines of interference increases
## Explanation
-Young explained the observed pattern with the Huygens wave theory and so introduced the principle of interference. Many textbooks give the explanation. {numref}`Figure {number} <6d1004/figure_2.png>` shows the arrangement: $s$ is very large compared to the slit separation $b$.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d1004/figure_2.png
----
+Young explained the observed pattern with the Huygens wave theory and so introduced the principle of interference. Many textbooks give the explanation. {numref}`Figure {number} <6d1004_figure_2.png>` shows the arrangement: $s$ is very large compared to the slit separation $b$.
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d1004_figure_2.png
+
.
```
In $P$, ray $r_{1}$ and ray $r_{2}$ interfere. This interference will be constructive when $r_{1}-r_{2}=m \lambda$ $(m=0,1,2,3, \ldots)$.
@@ -92,7 +89,6 @@ If a becomes vanishingly small, then the diffraction envelope term approaches 1
```{iframe} https://www.youtube.com/watch?v=OMVmppspf1E
:width: 70%
-:height: 300px
:align: center
Video embedded from https://www.youtube.com/@rhettallain/
diff --git a/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/qr_images/qrcode_watch_v_OMVmppspf1E.svg b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/qr_images/qrcode_watch_v_OMVmppspf1E.svg
new file mode 100644
index 00000000..d23a233b
--- /dev/null
+++ b/book/book/6 optics/6D interference/6D10 Interference From Two Sources/6D1004 Youngs Double Slit/qr_images/qrcode_watch_v_OMVmppspf1E.svg
@@ -0,0 +1 @@
+
\ No newline at end of file
diff --git a/book/book/6 optics/6D interference/6D20 Lasers/6D2001 Speckle Spots and random Diffraction/6D2001.md b/book/book/6 optics/6D interference/6D20 Lasers/6D2001 Speckle Spots and random Diffraction/6D2001.md
index ce694d2a..9eee0f34 100644
--- a/book/book/6 optics/6D interference/6D20 Lasers/6D2001 Speckle Spots and random Diffraction/6D2001.md
+++ b/book/book/6 optics/6D interference/6D20 Lasers/6D2001 Speckle Spots and random Diffraction/6D2001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d2001_figure_0.png
+
.
```
@@ -36,16 +35,15 @@ The room is darkened and the laser is switched on. An illuminated disk is projec
## Explanation
The laser light is scattered from a diffuse surface. This light is spatially coherent and it will fill the surrounding region with a stationary interference pattern. At any position in space the resultant field is the superposition of many contributing scattered wavelengths. A real system of fringes is formed of the scattered waves that converge in front of the screen. After forming the real image in space, the rays proceed to diverge, and any region of the image can therefore be viewed directly with the eye approximately focussed.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d2001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d2001_figure_1.png
+
.
```
The constructive and destructive interference occur in the eye.
-The diverging rays appear to the eye as if they had originated behind the scattering screen (see {numref}`Figure {number} <6d2001/figure_1.png>`). This is a result of chromatic aberration: normal and farsighted eyes tend to focus red light behind the screen. (A nearsighted person in front of the screen.)
+The diverging rays appear to the eye as if they had originated behind the scattering screen (see {numref}`Figure {number} <6d2001_figure_1.png>`). This is a result of chromatic aberration: normal and farsighted eyes tend to focus red light behind the screen. (A nearsighted person in front of the screen.)
## Sources
* Hecht, Eugene, Optics, pag. 595-596
diff --git a/book/book/6 optics/6D interference/6D30 Thin Films/6D3001 Newtons Rings/6D3001.md b/book/book/6 optics/6D interference/6D30 Thin Films/6D3001 Newtons Rings/6D3001.md
index 66ad7f84..eb2c8cb6 100644
--- a/book/book/6 optics/6D interference/6D30 Thin Films/6D3001 Newtons Rings/6D3001.md
+++ b/book/book/6 optics/6D interference/6D30 Thin Films/6D3001 Newtons Rings/6D3001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d3001_figure_0.png
+
.
```
@@ -26,28 +25,26 @@ name: 6d3001/figure_0.png
## Presentation
-The prism is placed on the convex side of the $5000 \mathrm{~mm}$-lens. The camera looks almost perpendicular at a side of the prism (see Diagram). The image is projected. Concentric Newton's rings are observed (see {numref}`Figure {number} <6d3001/figure_1.png>`).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d3001/figure_1.png
----
+The prism is placed on the convex side of the $5000 \mathrm{~mm}$-lens. The camera looks almost perpendicular at a side of the prism (see Diagram). The image is projected. Concentric Newton's rings are observed (see {numref}`Figure {number} <6d3001_figure_1.png>`).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d3001_figure_1.png
+
.
```
## Explanation
-{numref}`Figure {number} <6d3001/figure_2.png>` shows the setup of the demonstration and the way the light rays go towards the camera (eye). The thin film between the flat and convex surface causes a phase difference between the two reflected rays: Reflection from the plane gives a phase change of $\Delta \phi=0$ (the black ray); reflection from the convex surface gives a phase change of $\Delta \phi=\pi$, and next to this phase change of $\pi$ the transit-time in the short air wedge adds to this phase difference (the red ray).
+{numref}`Figure {number} <6d3001_figure_2.png>` shows the setup of the demonstration and the way the light rays go towards the camera (eye). The thin film between the flat and convex surface causes a phase difference between the two reflected rays: Reflection from the plane gives a phase change of $\Delta \phi=0$ (the black ray); reflection from the convex surface gives a phase change of $\Delta \phi=\pi$, and next to this phase change of $\pi$ the transit-time in the short air wedge adds to this phase difference (the red ray).
+
+The incoming light is diffuse, so when the camera (eye) is shifted, another pair of interfering rays is caught by the camera, and a changed pattern is observed (see the black- and green colored ray in {numref}`Figure {number} <6d3001_figure_2.png>`).
-The incoming light is diffuse, so when the camera (eye) is shifted, another pair of interfering rays is caught by the camera, and a changed pattern is observed (see the black- and green colored ray in {numref}`Figure {number} <6d3001/figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d3001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d3001/figure_2.png
----
.
```
-Using the $5000 \mathrm{~mm}$-lens makes the curvature in {numref}`Figure {number} <6d3001/figure_2.png>` much less and so the layer of air will change much slower in the $x$-direction, broadening the distance between the fringes.
+Using the $5000 \mathrm{~mm}$-lens makes the curvature in {numref}`Figure {number} <6d3001_figure_2.png>` much less and so the layer of air will change much slower in the $x$-direction, broadening the distance between the fringes.
## Remarks
- In literature this setup is also known as "interference prism".
diff --git a/book/book/6 optics/6D interference/6D30 Thin Films/6D3002 Newtons Rings/6D3002.md b/book/book/6 optics/6D interference/6D30 Thin Films/6D3002 Newtons Rings/6D3002.md
index 2426d8ac..e712658d 100644
--- a/book/book/6 optics/6D interference/6D30 Thin Films/6D3002 Newtons Rings/6D3002.md
+++ b/book/book/6 optics/6D interference/6D30 Thin Films/6D3002 Newtons Rings/6D3002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d3002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d3002_figure_0.png
+
.
```
@@ -31,31 +30,29 @@ name: 6d3002/figure_0.png
## Presentation
-Set up the equipment as shown in Diagram. Images are projected on the wall (see {numref}`Figure {number} <6d3002/figure_1.png>`A)
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d3002/figure_1.png
----
+Set up the equipment as shown in Diagram. Images are projected on the wall (see {numref}`Figure {number} <6d3002_figure_1.png>`A)
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d3002_figure_1.png
+
.
```
-After the lamp is heated up, situation of Diagram A is presented to the students, to indicate that there will be a reflected and a transmitted beam of light. Then the transmitted beam is blocked (black screen) and using the mirror and a $+150 \mathrm{~mm}$-lens the reflection image is projected (Diagram B). Clearly Newton's rings are observed. Observe the central dark spot (see also: Remarks) observe the colored rings, the color-sequence and observe the diminishing distance between the rings when moving away from the centre. Changing the pressure on the Newton's rings apparatus will change/move the reflected image. Then the black screen is removed and using the second $+150 \mathrm{~mm}$-lens the transmitted image is projected next to the reflected image (see Diagram C and {numref}`Figure {number} <6d3002/figure_1.png>`). It is clearly visible that both images are complementary.
+After the lamp is heated up, situation of Diagram A is presented to the students, to indicate that there will be a reflected and a transmitted beam of light. Then the transmitted beam is blocked (black screen) and using the mirror and a $+150 \mathrm{~mm}$-lens the reflection image is projected (Diagram B). Clearly Newton's rings are observed. Observe the central dark spot (see also: Remarks) observe the colored rings, the color-sequence and observe the diminishing distance between the rings when moving away from the centre. Changing the pressure on the Newton's rings apparatus will change/move the reflected image. Then the black screen is removed and using the second $+150 \mathrm{~mm}$-lens the transmitted image is projected next to the reflected image (see Diagram C and {numref}`Figure {number} <6d3002_figure_1.png>`). It is clearly visible that both images are complementary.
-At first glance, the observed colors look rainbowlike, but careful observation shows that it differs from a rainbow (see {numref}`Figure {number} <6d3002/figure_2.png>`; reality is much better than this photograph).
+At first glance, the observed colors look rainbowlike, but careful observation shows that it differs from a rainbow (see {numref}`Figure {number} <6d3002_figure_2.png>`; reality is much better than this photograph).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d3002_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d3002/figure_2.png
----
.
```
Observing the reflected image shows, when moving away from the central dark spot, at first a rainbow, but already in the next ring the color purple appears; in the next rings white and orange are dominating; around ring 10 there is a repeating sequence of blue and orange and around ring 16 repeating bands of dark violet and yellowish rings are visible giving form a distance the impression of a continuity of black and white fringes.
## Explanation
-See {numref}`Figure {number} <6d3002/figure_1.png>` B. Looking at the two red rays drawn in this figure, we see that it is the height $d$ that introduces the phasedifference. $d=R-\left(R^{2}-x^{2}\right)^{1 / 2}$.
+See {numref}`Figure {number} <6d3002_figure_1.png>` B. Looking at the two red rays drawn in this figure, we see that it is the height $d$ that introduces the phasedifference. $d=R-\left(R^{2}-x^{2}\right)^{1 / 2}$.
The two rays, one reflecting from the hemisphere and the other reflecting from the plane, will have a phasedifference of $\Delta \phi=k(2 d)-\pi$ ( $\pi$ at reflection off the plane).
@@ -63,17 +60,16 @@ Maximum, constructive interference will occur at $\Delta \varphi=\frac{4 \pi d}{
This result translated to the distance $x$ (because $x$ lies in the plane we are watching/projecting) yields $1 / 2 \lambda(m+1 / 2)=R-\left(R^{2}-x^{2}\right)^{1 / 2}$, giving $x=\{\lambda R(m+1 / 2)$ $\left.1 / 4 \lambda^{2}(m+1 / 2)^{2}\right\}^{1 / 2}$. And $R$ being much larger than $\lambda$ will give $x=\{\lambda R(m+1 / 2)\}^{1 / 2}$. First conclusion is that $x$ is proportional to the squareroot of wavelength. So a higher wavelength yields a higher $x$. blue is on the inside, red on the outside. Second, the proportionality in $(m+1 / 2)^{1 / 2}$ shows that the sequence of the bright fringes follows a square root: moving away from the centre the fringes come closer and closer together.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 6d3002/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 6d3002_figure_3.png
+
.
```
-Finally, we calculated for a number of $m$-values $x$. {numref}`Figure {number} <6d3002/figure_3.png>` shows the calculated results ( $10^{-5} ; \mathrm{R}=1 \mathrm{~m}$ ) for the red, green and blue line of $\mathrm{H}_{0}$-light. In this way it is clear that the colours observed are the result of different combinations. Only near the centre a rainbow pattern appears.
+Finally, we calculated for a number of $m$-values $x$. {numref}`Figure {number} <6d3002_figure_3.png>` shows the calculated results ( $10^{-5} ; \mathrm{R}=1 \mathrm{~m}$ ) for the red, green and blue line of $\mathrm{H}_{0}$-light. In this way it is clear that the colours observed are the result of different combinations. Only near the centre a rainbow pattern appears.
-It is not difficult now to show that for destructive interference we get $x=(\lambda R \mathrm{~m})^{1 / 2}$. This yields that the centre of the reflected Newton's rings must be a dark spot. {numref}`Figure {number} <6d3002/figure_3.png>` shows the minima as dashed lines for red, green and blue.
+It is not difficult now to show that for destructive interference we get $x=(\lambda R \mathrm{~m})^{1 / 2}$. This yields that the centre of the reflected Newton's rings must be a dark spot. {numref}`Figure {number} <6d3002_figure_3.png>` shows the minima as dashed lines for red, green and blue.
## Remarks
* Using filters, it is possible to show a monochromatic interference pattern. Especially in the yellow line of Hg the pattern is bright.
diff --git a/book/book/6 optics/6D interference/6D30 Thin Films/6D3003 Oil Film/6D3003.md b/book/book/6 optics/6D interference/6D30 Thin Films/6D3003 Oil Film/6D3003.md
index 9784cba7..0bbd9c77 100644
--- a/book/book/6 optics/6D interference/6D30 Thin Films/6D3003 Oil Film/6D3003.md
+++ b/book/book/6 optics/6D interference/6D30 Thin Films/6D3003 Oil Film/6D3003.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d3003/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d3003_figure_0.png
+
.
```
@@ -34,25 +33,23 @@ name: 6d3003/figure_0.png
## Presentation
The demonstration is prepared as shown in Diagram.
-First the demonstration is performed with white light, so the $200 \mathrm{~mm}$ lens should be placed near the Petri dish A. The dish is filled with a layer tap water. The lens projects an image of the water surface on the wall (see {numref}`Figure {number} <6d3003/figure_1.png>`A). By means of the wash bottle a drop of oil is deposited on the water surface. The drop spreads out quickly, no colors are observed; only the very attentive students have seen colors at the rim of the oil spot that moved quickly outwards.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d3003/figure_1.png
----
+First the demonstration is performed with white light, so the $200 \mathrm{~mm}$ lens should be placed near the Petri dish A. The dish is filled with a layer tap water. The lens projects an image of the water surface on the wall (see {numref}`Figure {number} <6d3003_figure_1.png>`A). By means of the wash bottle a drop of oil is deposited on the water surface. The drop spreads out quickly, no colors are observed; only the very attentive students have seen colors at the rim of the oil spot that moved quickly outwards.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d3003_figure_1.png
+
.
```
-The Petri dish is cleaned and a new layer of tap water is poured in it. The thin stick is dipped in the oil and by tipping the stick on the water surface a small oil drop is positioned on it. Immediately it spreads outward in a spot and clearly colors are observed (see {numref}`Figure {number} <6d3003/figure_1.png>`B). After a short while the broadening stops and the oil spot is seen showing one color only (sometimes reddish or yellowish or green or blue or.. -see {numref}`Figure {number} <6d3003/figure_1.png>`C). In applying more small drops of oil on the preceding oil spot, the process of observing changing color patterns can be repeated. The advantage of placing drops on the preceding oil spots is that the speed by which the colors move and change diminishes and the process can be followed better.
+The Petri dish is cleaned and a new layer of tap water is poured in it. The thin stick is dipped in the oil and by tipping the stick on the water surface a small oil drop is positioned on it. Immediately it spreads outward in a spot and clearly colors are observed (see {numref}`Figure {number} <6d3003_figure_1.png>`B). After a short while the broadening stops and the oil spot is seen showing one color only (sometimes reddish or yellowish or green or blue or.. -see {numref}`Figure {number} <6d3003_figure_1.png>`C). In applying more small drops of oil on the preceding oil spot, the process of observing changing color patterns can be repeated. The advantage of placing drops on the preceding oil spots is that the speed by which the colors move and change diminishes and the process can be followed better.
The demonstration is repeated in monochromatic red laser light. The $10 \mathrm{~mm}$-lens makes a diverging bundle of light and via the surface mirror the water in Petri dish $\mathrm{B}$ is exposed. Using the stick, a small drop of oil is put on the water surface. It is really amazing how clearly visible the fringed pattern of closely spaced black and red circles appears and broadens. Also in this demonstration the process of broadening is slowed down when applying more drops of oil on the foregoing oil spots.
## Explanation
-The thin oil film (thickness in the order of the wavelength used) serves as an amplitude splitting device (see {numref}`Figure {number} <6d3003/figure_2.png>`).
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d3003/figure_2.png
----
+The thin oil film (thickness in the order of the wavelength used) serves as an amplitude splitting device (see {numref}`Figure {number} <6d3003_figure_2.png>`).
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d3003_figure_2.png
+
.
```
Light reflects from the top and from the bottom of the oilfilm (from the first - and the second interface), so that $\mathrm{E}_{1 \text { r }}$ and $\mathrm{E}_{2 \mathrm{r}}$ may be considered as arising from two coherent sources ( $\mathrm{S}_{1}$ and $\mathrm{S}_{2}$ ). When the two parallel reflected rays are brought together on the retina of the eye, they add up, producing interference of light. (In this demonstration the $200 \mathrm{~mm}$ lens brings the parallel rays together in the projection on the wall.) There is a phas edifference between the two rays of
diff --git a/book/book/6 optics/6D interference/6D30 Thin Films/6D3004 Soap Film/6D3004.md b/book/book/6 optics/6D interference/6D30 Thin Films/6D3004 Soap Film/6D3004.md
index 206a34a2..49981658 100644
--- a/book/book/6 optics/6D interference/6D30 Thin Films/6D3004 Soap Film/6D3004.md
+++ b/book/book/6 optics/6D interference/6D30 Thin Films/6D3004 Soap Film/6D3004.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6d3004/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6d3004_figure_0.png
+
.
```
@@ -29,14 +28,13 @@ name: 6d3004/figure_0.png
## Presentation
Having set up the demonstration as shown in Diagram, an image of the rim of the wineglass is projected on the wall. Using a felt pen you mark the position of the wineglass on the table. Using your finger you can show that the projected image is upside down. Dip the wineglass in the soap solution, so that the rim of the glass has a film on it. Put the glass back in its marked position.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6d3004/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6d3004_figure_1.png
+
.
```
-First, the image is whitish, but very soon a reddish haze appears, transforming into red and white stripes. Gradually more colors appear (see {numref}`Figure {number} <6d3004/figure_1.png>`A) and when full color rainbows appear, also black stripes show themselves. Finally a broad whitish band appears on the upper side, abruptly followed by complete darkness (see {numref}`Figure {number} <6d3004/figure_1.png>`B). Then the film breaks.
+First, the image is whitish, but very soon a reddish haze appears, transforming into red and white stripes. Gradually more colors appear (see {numref}`Figure {number} <6d3004_figure_1.png>`A) and when full color rainbows appear, also black stripes show themselves. Finally a broad whitish band appears on the upper side, abruptly followed by complete darkness (see {numref}`Figure {number} <6d3004_figure_1.png>`B). Then the film breaks.
The demonstration is repeated a couple of times because the color transformations go pretty fast. Sometimes it needs to be repeated because the soap film breaks too soon.
@@ -55,15 +53,14 @@ Going down the film until it is $1 / 4$ wavelength of blue light in thickness th
When the film is $1 / 2$ of a wavelength of blue light thick the blue waves cancel. But now the film is also $1 / 4$ of the wavelength of red light thick, and the red light is reflected strongly. Every integral multiple of $1 / 2$ blue wavelength, blue light is removed, every odd multiple of $1 / 4$ wavelength of blue light is strengthened.
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6d3004/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6d3004_figure_2.png
+
.
```
-The same holds for red light. {numref}`Figure {number} <6d3004/figure_2.png>` shows the result of this simplified blue-red dance. This figure clarifies that red dominates blue: the maximum of blue has always some red in it, while the maximum of red is "pure" red. In incandescent lamplight this is even stronger, due to the fact that red has a higher intensity in that light than blue.
+The same holds for red light. {numref}`Figure {number} <6d3004_figure_2.png>` shows the result of this simplified blue-red dance. This figure clarifies that red dominates blue: the maximum of blue has always some red in it, while the maximum of red is "pure" red. In incandescent lamplight this is even stronger, due to the fact that red has a higher intensity in that light than blue.
## Remarks
* The color pattern can also be easily observed in normal daylight. But for a larger group projection will be necessary.
diff --git a/book/book/6 optics/6F color/6F30 Dispersion/6F3001 Chromatic Aberration/6F3001.md b/book/book/6 optics/6F color/6F30 Dispersion/6F3001 Chromatic Aberration/6F3001.md
index cfe8133d..fdf3ec32 100644
--- a/book/book/6 optics/6F color/6F30 Dispersion/6F3001 Chromatic Aberration/6F3001.md
+++ b/book/book/6 optics/6F color/6F30 Dispersion/6F3001 Chromatic Aberration/6F3001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6f3001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6f3001_figure_0.png
+
.
```
@@ -43,12 +42,11 @@ When the $150 \mathrm{~mm}$ single lens is replaced by the doublet of $150 \math
## Explanation
Since the thin-lens equation $\frac{1}{f}=\left(n_{t}-1\right)\left(\frac{1}{R_{1}}-\frac{1}{R_{2}}\right)$ is wavelength-dependent via $n_{1}(\lambda)$
-(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6f3001/figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6f3001/figure_1.png
----
+(dispersion), the focal length must also vary with $\lambda$ ({numref}`Figure {number} <6f3001_figure_1.png>` shows the graph of $n$, versus $\lambda$ of crown-glass.).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6f3001_figure_1.png
+
.
```
In general $n_{1}(\lambda)$ decreases with wavelength over the visible region, and thus $f(\lambda)$ increases with $\lambda$. And when $f(\lambda)$ increases with $\lambda$, then also the image-distance increases with $\lambda$ (object-distance is constant). The demonstration shows this: the red image being sharp at a larger distance than the blue image.
diff --git a/book/book/6 optics/6H polarisation/6H20 Reflection/6H2001 Brewsters Angle/6H2001.md b/book/book/6 optics/6H polarisation/6H20 Reflection/6H2001 Brewsters Angle/6H2001.md
index bdd9befe..68a9a28c 100644
--- a/book/book/6 optics/6H polarisation/6H20 Reflection/6H2001 Brewsters Angle/6H2001.md
+++ b/book/book/6 optics/6H polarisation/6H20 Reflection/6H2001 Brewsters Angle/6H2001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6h2001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6h2001_figure_0.png
+
.
```
@@ -31,15 +30,14 @@ name: 6h2001/figure_0.png
## Presentation
Etienne Malus was standing at the window of his house in the Rue d'Enfer (Paris) examining a calcite crystal. The sun was setting, and its image reflected towards him from the windows of the Luxembourg Palace not far away. He held up the crystal and looked through it at the sun's reflection. To his astonishment, he saw one of the double images of the sun disappear as he rotated the calcite!
-This historical situation is presented in our demonstration (see Diagram). The 12Vlamp is in our situation operating at $6 \mathrm{~V}$ in series with a $2 \Omega / 20 \mathrm{~W}$ resistor. This is the red glowing setting sun. The acrylic sheet is a window of the palace and the camera is the eye of Etienne Malus. The beamer projects to the audience the image that Etienne saw: "window" and reflected image of the "sun" (see {numref}`Figure {number} <6h2001/figure_1.png>`A). Take care that the camera is focussed on the light spot and not on the "window" itself.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6h2001/figure_1.png
----
+This historical situation is presented in our demonstration (see Diagram). The 12Vlamp is in our situation operating at $6 \mathrm{~V}$ in series with a $2 \Omega / 20 \mathrm{~W}$ resistor. This is the red glowing setting sun. The acrylic sheet is a window of the palace and the camera is the eye of Etienne Malus. The beamer projects to the audience the image that Etienne saw: "window" and reflected image of the "sun" (see {numref}`Figure {number} <6h2001_figure_1.png>`A). Take care that the camera is focussed on the light spot and not on the "window" itself.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6h2001_figure_1.png
+
.
```
-The lay-out of the demonstration is such that the angle of incidence is about $60^{\circ}$. The large $30-60-90^{\circ}$ triangle shows this to the students. Now the calcite crystal is placed in front of the camera-lens (see {numref}`Figure {number} <6h2001/figure_1.png>`B). Everything in the projected image is doubled. While rotating the crystal also the double images rotate, but at two positions of rotation the doubling of the reflected "sun" disappears and only one "sun" is seen!
+The lay-out of the demonstration is such that the angle of incidence is about $60^{\circ}$. The large $30-60-90^{\circ}$ triangle shows this to the students. Now the calcite crystal is placed in front of the camera-lens (see {numref}`Figure {number} <6h2001_figure_1.png>`B). Everything in the projected image is doubled. While rotating the crystal also the double images rotate, but at two positions of rotation the doubling of the reflected "sun" disappears and only one "sun" is seen!
Observe also that the double image of the window never disappears.
## Explanation
@@ -53,13 +51,12 @@ coefficient equals: $t_{\text {par }}=\frac{2 n_{i} \cos \theta_{i}}{n_{i} \cos
and $t_{\text {perp }}=\frac{2 n_{i} \cos \theta_{i}}{n_{i} \cos \theta_{i}+n_{t} \cos \theta_{t}}$
-{numref}`Figure {number} <6h2001/figure_2.png>` shows these formulas in a graph (as function of the angle of incidence).
+{numref}`Figure {number} <6h2001_figure_2.png>` shows these formulas in a graph (as function of the angle of incidence).
+
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 6h2001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 6h2001/figure_2.png
----
.
```
There appears zero amplitude for $r_{p a r}$ at a certain angle. This angle can be found when using Snell's law in $r_{p a r}: r_{\text {par }}=\frac{\sin \theta_{i} \cos \theta_{i}-\sin \theta_{t} \cos \theta_{t}}{\sin \theta_{i} \cos \theta_{i}+\sin \theta_{t} \cos \theta_{t}}$. Rewriting (see textbooks) $r_{\text {par }}=\frac{\tan \left(\theta_{i}-\theta_{t}\right)}{\tan \left(\theta+\theta_{i} \theta_{t}\right)}$
diff --git a/book/book/6 optics/6H polarisation/6H20 Reflection/6H2002 Brewsters Angle/6H2002.md b/book/book/6 optics/6H polarisation/6H20 Reflection/6H2002 Brewsters Angle/6H2002.md
index c936da71..4e5836cd 100644
--- a/book/book/6 optics/6H polarisation/6H20 Reflection/6H2002 Brewsters Angle/6H2002.md
+++ b/book/book/6 optics/6H polarisation/6H20 Reflection/6H2002 Brewsters Angle/6H2002.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 6h2002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 6h2002_figure_0.png
+
.
```
@@ -29,31 +28,29 @@ name: 6h2002/figure_0.png
## Presentation
The demonstration is presented as shown in Diagram. The angle of incidence is about $60^{\circ}$. In this lay-out the plane of incidence is horizontal.
-Switching on the lamp and shifting the condenser, a parallel beam of light is made. On the blackboard the transmitted beam through the acrylic sheet is observed and the black screen shows that there is also a (weaker) reflected beam (see Diagram). When the Polaroid filter is placed in the beam of light, having its direction of polarization parallel to the plane of incidence, the reflected wave disappears (see {numref}`Figure {number} <6h2002/figure_1.png>`A): there is only transmission.
+Switching on the lamp and shifting the condenser, a parallel beam of light is made. On the blackboard the transmitted beam through the acrylic sheet is observed and the black screen shows that there is also a (weaker) reflected beam (see Diagram). When the Polaroid filter is placed in the beam of light, having its direction of polarization parallel to the plane of incidence, the reflected wave disappears (see {numref}`Figure {number} <6h2002_figure_1.png>`A): there is only transmission.
+
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 6h2002_figure_1.png
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 6h2002/figure_1.png
----
.
```
When the Polaroid is rotated there is again reflection. Figure $1 B$ shows the situation when the direction of polarization is perpendicular to the plane of incidence.
## Explanation
The refracted wave entering the acrylic sheet drives the bound electrons and they in turn reradiate.
-```{figure} figures/figure_2_old.png
----
-width: 70%
-name: 6h2002/figure_2.png
----
+```{figure} figures/figure_2_old.png
+:width: 70%
+:label: 6h2002_figure_2.png
+
.
```
-{numref}`Figure {number} <6h2002/figure_2.png>`A shows such a dipole radiation pattern (green line is the envelope) of such an oscillating charge. If the situation is arranged such that $\theta_{r}+\theta_{t}=90^{\circ}$, there is no reradiation into the direction of reflection (see {numref}`Figure {number} <6h2002/figure_2.png>`B ): the reflected wave vanishes. (In a simple way you can say that in the direction of reflection an observer "sees" no oscillation). The angle at which this situation happens is called Brewster's angle $\left(\theta_{p}\right.$ )
+{numref}`Figure {number} <6h2002_figure_2.png>`A shows such a dipole radiation pattern (green line is the envelope) of such an oscillating charge. If the situation is arranged such that $\theta_{r}+\theta_{t}=90^{\circ}$, there is no reradiation into the direction of reflection (see {numref}`Figure {number} <6h2002_figure_2.png>`B ): the reflected wave vanishes. (In a simple way you can say that in the direction of reflection an observer "sees" no oscillation). The angle at which this situation happens is called Brewster's angle $\left(\theta_{p}\right.$ )
## Remarks
* Also see the demonstration [Brewster's angle (1)](<../6H2001 Brewsters Angle/6H2001.md) .
- * The pictures in Diagram, {numref}`Figure {number} <6h2002/figure_1.png>`A and -1B show that in this demonstration you can also say something about the intensities of the reflected and transmitted beams. {numref}`Figure {number} <6h2002/figure_2.png>` in the demonstration [Brewster's angle](../6H2001 Brewsters Angle/6H2001.md) can be used to elucidate the observed differences in intensities.
+ * The pictures in Diagram, {numref}`Figure {number} <6h2002_figure_1.png>`A and -1B show that in this demonstration you can also say something about the intensities of the reflected and transmitted beams. {numref}`Figure {number} <6h2002_figure_2.png>` in the demonstration [Brewster's angle](../6H2001 Brewsters Angle/6H2001.md) can be used to elucidate the observed differences in intensities.
## Sources
diff --git a/book/book/7 modern physics/7A quantum effects/7A50 Wave Mechanics/7A5002 Tunneling/7A5002.md b/book/book/7 modern physics/7A quantum effects/7A50 Wave Mechanics/7A5002 Tunneling/7A5002.md
index c082468c..77ee9237 100644
--- a/book/book/7 modern physics/7A quantum effects/7A50 Wave Mechanics/7A5002 Tunneling/7A5002.md
+++ b/book/book/7 modern physics/7A quantum effects/7A50 Wave Mechanics/7A5002 Tunneling/7A5002.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 7a5002/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 7a5002_figure_0.png
+
.
```
@@ -40,12 +39,11 @@ The camera and monitor are placed in order to make the gap between the paraffin
The slideway is needed in order to shift one of the paraffin wax triangles along a straight line.
-When you prepare the demonstration, use the set ups as shown in {numref}`Figure {number} <7a5002/figure_1.png>`B and -C: In {numref}`Figure {number} <7a5002/figure_1.png>`B, the meter, indicating the signal received by R1, should be equal to the signal that will be received by R2 in the situation of {numref}`Figure {number} <7a5002/figure_1.png>`C. To achieve this, careful positioning is needed for sender $\mathrm{S}$, the paraffin wax blocks and both receivers.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 7a5002/figure_1.png
----
+When you prepare the demonstration, use the set ups as shown in {numref}`Figure {number} <7a5002_figure_1.png>`B and -C: In {numref}`Figure {number} <7a5002_figure_1.png>`B, the meter, indicating the signal received by R1, should be equal to the signal that will be received by R2 in the situation of {numref}`Figure {number} <7a5002_figure_1.png>`C. To achieve this, careful positioning is needed for sender $\mathrm{S}$, the paraffin wax blocks and both receivers.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 7a5002_figure_1.png
+
.
```
## Presentation
@@ -64,11 +62,10 @@ Figure C
A triangular block of paraffine wax is placed in front of the sender $S$ as shown in Figure B. Receiver R1 has no deflection, so it receives no signal. But receiver R2 shows a deflection, and this deflection is equal to that of the previous situation (Figure A). Clearly the signal from the sender is deflected by the paraffin block towards R2. Again the comparison with glass and light can be made. (Optional: show this with a laser and a rectangular prism)
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 7a5002/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 7a5002_figure_2.png
+
.
```
## Figure D-E
@@ -80,7 +77,7 @@ The weirdness of this phenomenon should be stressed, by mentioning that if in si
(Optional: Show that laser light that enters a beam splitter is partially transmitted and partially deflected)
## Explanation
-Apparently, the transition from wax to air into the straight on direction towards R1, as in {numref}`Figure {number} <7a5002/figure_1.png>`C, is a barrier to the microwaves, but not completely (as in {numref}`Figure {number} <7a5002/figure_2.png>`D and $-\mathrm{E}$ ).
+Apparently, the transition from wax to air into the straight on direction towards R1, as in {numref}`Figure {number} <7a5002_figure_1.png>`C, is a barrier to the microwaves, but not completely (as in {numref}`Figure {number} <7a5002_figure_2.png>`D and $-\mathrm{E}$ ).
Solving the Schroedinger wave equation provides a satisfying solution, because this shows that within a barrier the solution to the wave equation is decaying exponential, dying away to zero, and so, if that barrier ends before this zero is reached, then there is again a sinusoidal wave function. (See the many textbooks on this subject.)
## Remarks
diff --git a/book/book/7 modern physics/7A quantum effects/7A60 X ray and Electron Diffraction/7A6001 Bragg Scattering/7A6001.md b/book/book/7 modern physics/7A quantum effects/7A60 X ray and Electron Diffraction/7A6001 Bragg Scattering/7A6001.md
index e0bf7da4..f0ad1bbe 100644
--- a/book/book/7 modern physics/7A quantum effects/7A60 X ray and Electron Diffraction/7A6001 Bragg Scattering/7A6001.md
+++ b/book/book/7 modern physics/7A quantum effects/7A60 X ray and Electron Diffraction/7A6001 Bragg Scattering/7A6001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 7a6001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 7a6001_figure_0.png
+
.
```
@@ -36,26 +35,24 @@ We simulate such an experiment using cm-waves instead of $\mathrm{X}$-rays and a
First, the sender and receiver face each other. (A camera, perpendicular above the set-up, projects the lay-out to the audience.) The large demonstration meter is adjusted to give a sufficient deflection. Putting your hand between sender and receiver reduces the received signal to zero. Then a large piece of plastic foam is placed between the sender and receiver. It fills that space completely, but the receiver still shows the same intensity of received signal: To these cm-waves the plastic foam is perfectly transparent.
-Then the crystal model is placed between the sender and receiver on the rotatable table The crystal's plane $\mathrm{A}(100)$ is perpendicular to the incident microwave beam (see {numref}`Figure {number} <7a6001/figure_1.png>`A). The received signal is lower now. Conclusion must be that the array of steel balls is responsible for this signal reduction (see also Remarks).
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 7a6001/figure_1.png
----
+Then the crystal model is placed between the sender and receiver on the rotatable table The crystal's plane $\mathrm{A}(100)$ is perpendicular to the incident microwave beam (see {numref}`Figure {number} <7a6001_figure_1.png>`A). The received signal is lower now. Conclusion must be that the array of steel balls is responsible for this signal reduction (see also Remarks).
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 7a6001_figure_1.png
+
.
```
-Following the suggestion of Von Laue that there could be diffraction due to the crystal lattice, we rotate ( $\alpha$ ) the receiver slowly around the crystal, using the arm of the goniometer (see {numref}`Figure {number} <7a6001/figure_1.png>`B). Off $\alpha=0^{\circ}$ the receiver signal diminishes and no relevant signal is found at any angle $\alpha$.
+Following the suggestion of Von Laue that there could be diffraction due to the crystal lattice, we rotate ( $\alpha$ ) the receiver slowly around the crystal, using the arm of the goniometer (see {numref}`Figure {number} <7a6001_figure_1.png>`B). Off $\alpha=0^{\circ}$ the receiver signal diminishes and no relevant signal is found at any angle $\alpha$.
+
+The demonstration is repeated with a different orientation of the crystal. The number of orientations is, of course, infinitive, so we choose a number of possibilities (see {numref}`Figure {number} <7a6001_figure_1.png>`A). Orientation $\mathrm{A}(100)$ is done, next we try $\mathrm{B}(410)$, then $\mathrm{C}(210)$ and so on. (The green bar shows the orientation to the audience; see green bar in {numref}`Figure {number} <7a6001_figure_2.png>`.)
-The demonstration is repeated with a different orientation of the crystal. The number of orientations is, of course, infinitive, so we choose a number of possibilities (see {numref}`Figure {number} <7a6001/figure_1.png>`A). Orientation $\mathrm{A}(100)$ is done, next we try $\mathrm{B}(410)$, then $\mathrm{C}(210)$ and so on. (The green bar shows the orientation to the audience; see green bar in {numref}`Figure {number} <7a6001/figure_2.png>`.)
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 7a6001_figure_2.png
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 7a6001/figure_2.png
----
.
```
-B shows no relevant result, but $\mathrm{C}$ shows a peak when the angle of rotation, $\alpha$, is a little bit more than $45^{\circ}$. Observing the position of sender receiver and crystal planes, symmetry is observed! We aid this observation by placing the red stick in the direction of the (100) plane (see {numref}`Figure {number} <7a6001/figure_2.png>`). This strongly suggests that the peak measured is due to reflections off the (100) planes of the crystal. In this symmetry-situation $\alpha=2 \phi, \phi$ being the so-called grazing angle (or glancing angle). In this situation that grazing angle is around $22.5^{\circ}$.
+B shows no relevant result, but $\mathrm{C}$ shows a peak when the angle of rotation, $\alpha$, is a little bit more than $45^{\circ}$. Observing the position of sender receiver and crystal planes, symmetry is observed! We aid this observation by placing the red stick in the direction of the (100) plane (see {numref}`Figure {number} <7a6001_figure_2.png>`). This strongly suggests that the peak measured is due to reflections off the (100) planes of the crystal. In this symmetry-situation $\alpha=2 \phi, \phi$ being the so-called grazing angle (or glancing angle). In this situation that grazing angle is around $22.5^{\circ}$.
All other orientations of the crystal give no relevant result, except orientation $\mathrm{G}$, where a weak peak is measured at $\alpha$ of around $60^{\circ}$. Observing the position of sender, receiver and crystal in this situation makes us placing the red-stick-of-symmetry along the diagonal of the crystal (plane (110)). The grazing angle $\phi$ is then around $30^{\circ}$.
diff --git a/book/book/7 modern physics/7B atomic physics/7B10 Spectra/7B1001 Balmer Series/7B1001.md b/book/book/7 modern physics/7B atomic physics/7B10 Spectra/7B1001 Balmer Series/7B1001.md
index 1761736a..4ff9131d 100644
--- a/book/book/7 modern physics/7B atomic physics/7B10 Spectra/7B1001 Balmer Series/7B1001.md
+++ b/book/book/7 modern physics/7B atomic physics/7B10 Spectra/7B1001 Balmer Series/7B1001.md
@@ -8,11 +8,10 @@
* 7B10 (Spectra)
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 7b1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 7b1001_figure_0.png
+
.
```
@@ -40,12 +39,11 @@ name: 7b1001/figure_0.png
The gas discharge lamp and the two lenses are placed on the optical rail. The power supply of the lamp is switched on. Steady discharge is reached after approx. 15 minutes (see "notes on operation" of Leybold Didactic).
-The $+50 \mathrm{~mm}$ lens is shifted close to the lamp to focus as much light as possible through the $+150 \mathrm{~mm}$ lens. Both lenses are fixed. Then the variable slit and camera (mounted on the linear positioner and connected to the beamer; see {numref}`Figure {number} <7b1001/figure_1.png>`) are positioned on the optical rail. The slit is shifted to image it sharply on the camera CCD-screen. The linear positioner is shifted also, until the slit can be seen on the middle of the projected image.
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 7b1001/figure_1.png
----
+The $+50 \mathrm{~mm}$ lens is shifted close to the lamp to focus as much light as possible through the $+150 \mathrm{~mm}$ lens. Both lenses are fixed. Then the variable slit and camera (mounted on the linear positioner and connected to the beamer; see {numref}`Figure {number} <7b1001_figure_1.png>`) are positioned on the optical rail. The slit is shifted to image it sharply on the camera CCD-screen. The linear positioner is shifted also, until the slit can be seen on the middle of the projected image.
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 7b1001_figure_1.png
+
.
```
## Demonstration
@@ -53,20 +51,18 @@ name: 7b1001/figure_1.png
The room is darkened and a sharp and intense image of the slit is visible to the audience. Then the grating is placed in its holder as close as possible to the camera. We also place the black tube around the set-up (see Diagram B). Blue and red lines appear (also a fainting of the slit-image can be observed when the grating is placed). In this way we have build a spectroscope, like Fraunhofer did (1814).
The students are invited to describe what they see:
-```{figure} figures/figure_2.png
----
-width: 70%
-name: 7b1001/figure_2.png
----
+```{figure} figures/figure_2.png
+:width: 70%
+:label: 7b1001_figure_2.png
+
.
```
*“... diffraction pattern of a grating; first and second orders on both sides of the central maximum; blue is closer to the central maximum then red; ..."*
We shift the camera sideways so that the central maximum is on one side of the projected image. Then we ask the students what will happen when we shift the grating away from the camera. After their answering we shift it away and observe the broadening of the orders, but the pattern remains the same. In the shifting also a faint violet line ( $v$ ) can be seen.
-```{figure} figures/figure_3.png
----
-width: 70%
-name: 7b1001/figure_3.png
----
+```{figure} figures/figure_3.png
+:width: 70%
+:label: 7b1001_figure_3.png
+
.
```
The image is partly projected on the blackboard and we indicate with chalk the horizontal positions of: Central maximum (Cm), violet(v) -, blue(b) - and red(r) line. With a measuring tape we found:
@@ -80,15 +76,14 @@ $Cm-r=256 \mathrm{~cm}$
An explanation of what is observed now follows.
## Explanation
-Calibration is performed by using $\sin \theta=\frac{\lambda}{d}$ (first order maximum of a diffraction pattern created by a grating, $d$ being the distance between the slits of the grating.), see {numref}`Figure {number} <7b1001/figure_2.png>`.
-```{figure} figures/figure_4.png
----
-width: 70%
-name: 7b1001/figure_4.png
----
+Calibration is performed by using $\sin \theta=\frac{\lambda}{d}$ (first order maximum of a diffraction pattern created by a grating, $d$ being the distance between the slits of the grating.), see {numref}`Figure {number} <7b1001_figure_2.png>`.
+```{figure} figures/figure_4.png
+:width: 70%
+:label: 7b1001_figure_4.png
+
.
```
-{numref}`Figure {number} <7b1001/figure_2.png>` shows: $\sin \theta=\frac{x}{\sqrt{x^{2}+s^{2}}}$. Rewriting we get: $x=s \frac{\lambda}{\sqrt{d^{2}-\lambda^{2}}}$. When $\lambda \ll d$ then $x$ is directly proportional to $\lambda$. Since we do not know s exactly we cannot calibrate our spectroscope. But we can compare the different first order colors like Balmer did. Using our tape measurements we find:
+{numref}`Figure {number} <7b1001_figure_2.png>` shows: $\sin \theta=\frac{x}{\sqrt{x^{2}+s^{2}}}$. Rewriting we get: $x=s \frac{\lambda}{\sqrt{d^{2}-\lambda^{2}}}$. When $\lambda \ll d$ then $x$ is directly proportional to $\lambda$. Since we do not know s exactly we cannot calibrate our spectroscope. But we can compare the different first order colors like Balmer did. Using our tape measurements we find:
$$
\frac{C m-r}{C m-b}=\frac{256}{188}=1,36 ; \frac{C m-r}{C m-v}=\frac{256}{170}=1,51 ; \frac{C m-b}{C m-v}=\frac{188}{170}=1,11
diff --git a/book/book/7 modern physics/7B atomic physics/7B50 Atomic Models/7B5001 deBroglie Applied to Bohr/7B5001.md b/book/book/7 modern physics/7B atomic physics/7B50 Atomic Models/7B5001 deBroglie Applied to Bohr/7B5001.md
index 5b8478eb..3defd3f1 100644
--- a/book/book/7 modern physics/7B atomic physics/7B50 Atomic Models/7B5001 deBroglie Applied to Bohr/7B5001.md
+++ b/book/book/7 modern physics/7B atomic physics/7B50 Atomic Models/7B5001 deBroglie Applied to Bohr/7B5001.md
@@ -9,11 +9,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 7b5001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 7b5001_figure_0.png
+
.
```
@@ -34,21 +33,20 @@ name: 7b5001/figure_0.png
The wire loop is fitted to the mechanical wave driver shaft. The wave driver is connected to the signal generator. The image of wire loop and display of the frequency of the driving generator is projected (see Diagram).
Start at low frequency (around $5 \mathrm{~Hz}$ ) and low amplitude, making the loop starting to vibrate. Increase the frequency to see various modes of standing waves in the circular loop. (At higher frequencies the amplitude of the signal generator has to increase to obtain visible amplitude in the oscillating wire loop.) We observe:
-```{figure} figures/figure_1.png
----
-width: 70%
-name: 7b5001/figure_1.png
----
+```{figure} figures/figure_1.png
+:width: 70%
+:label: 7b5001_figure_1.png
+
.
```
- 2 nodes and anti-nodes at $14 \mathrm{~Hz}$;
-- 3 nodes and anti-nodes at $23 \mathrm{~Hz}$ (very large amplitude) (see {numref}`Figure {number} <7b5001/figure_1.png>`A);
+- 3 nodes and anti-nodes at $23 \mathrm{~Hz}$ (very large amplitude) (see {numref}`Figure {number} <7b5001_figure_1.png>`A);
- 4 nodes and anti-nodes at $30 \mathrm{~Hz}$;
-- 5 nodes and anti-nodes at $76 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001/figure_1.png>`B);
+- 5 nodes and anti-nodes at $76 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001_figure_1.png>`B);
-- 7 nodes and anti-nodes at $163 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001/figure_1.png>`C);
+- 7 nodes and anti-nodes at $163 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001_figure_1.png>`C);
-- 9 nodes and anti-nodes at $273 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001/figure_1.png>`D);
+- 9 nodes and anti-nodes at $273 \mathrm{~Hz}$ (see {numref}`Figure {number} <7b5001_figure_1.png>`D);
-11 nodes and anti-nodes at $398 \mathrm{~Hz}$ (this last one is not so good visible to a larger audience due to its low amplitude).
diff --git a/book/book/7 modern physics/7F relativity/7F10 Relativity/7F1001 E mc2/7F1001.md b/book/book/7 modern physics/7F relativity/7F10 Relativity/7F1001 E mc2/7F1001.md
index a705519e..c59b64ed 100644
--- a/book/book/7 modern physics/7F relativity/7F10 Relativity/7F1001 E mc2/7F1001.md
+++ b/book/book/7 modern physics/7F relativity/7F10 Relativity/7F1001 E mc2/7F1001.md
@@ -8,11 +8,10 @@
## Diagram
-```{figure} figures/figure_0.png
----
-width: 70%
-name: 7f1001/figure_0.png
----
+```{figure} figures/figure_0.png
+:width: 70%
+:label: 7f1001_figure_0.png
+
.
```
diff --git a/book/export.yml b/book/export.yml
new file mode 100644
index 00000000..f7433482
--- /dev/null
+++ b/book/export.yml
@@ -0,0 +1,54 @@
+version: 1
+project:
+
+ plugins:
+# - https://github.com/jupyter-book/myst-plugins/releases/download/iframe-to-qr-pdf/iframe-to-qr-pdf.mjs
+ - iframe-to-qr-pdf.mjs
+ - typst.mjs
+
+ downloads:
+ - id: output-pdf
+
+ exports:
+ - id: output-pdf
+ format: typst
+ template: https://github.com/myst-templates/plain_typst_book.git
+ output: export/demobook.pdf
+# additional options #
+
+# Include a figure at the cover page
+ cover: figures/coverbook.jpg
+ coverposition: 2 #in cm from title
+ cover_width: 12 #in cm
+
+# ToC
+ ToC_depth: 2
+ show_ToC: true
+
+# Page settings
+ #### Logo at top of position
+ # logo: logo.svg
+ # logo_width: 10
+
+ #### Looks
+ papersize: a4
+ margin_top: 2 #cm
+ margin_bottom: 2 #cm
+ margin_left: 10 #%
+ margin_right: 10 #%
+ show_pagenumber: true
+
+ #### Fonts
+ fontsize: 12
+ fontstyle:
+ linespacing: .5
+ justification: false
+
+ #### Theme
+ colortheme: blue.darken(30%)
+ colorheadings: navy
+
+# Preface
+ preface:
+
+
diff --git a/book/export/demobook.pdf b/book/export/demobook.pdf
new file mode 100644
index 00000000..5612180b
Binary files /dev/null and b/book/export/demobook.pdf differ
diff --git a/book/iframe-to-qr-pdf.mjs b/book/iframe-to-qr-pdf.mjs
new file mode 100644
index 00000000..d8d625da
--- /dev/null
+++ b/book/iframe-to-qr-pdf.mjs
@@ -0,0 +1,1736 @@
+// ../../../../../node_modules/qrcode-generator/dist/qrcode.mjs
+var qrcode = function(typeNumber, errorCorrectionLevel) {
+ const PAD0 = 236;
+ const PAD1 = 17;
+ let _typeNumber = typeNumber;
+ const _errorCorrectionLevel = QRErrorCorrectionLevel[errorCorrectionLevel];
+ let _modules = null;
+ let _moduleCount = 0;
+ let _dataCache = null;
+ const _dataList = [];
+ const _this = {};
+ const makeImpl = function(test, maskPattern) {
+ _moduleCount = _typeNumber * 4 + 17;
+ _modules = (function(moduleCount) {
+ const modules = new Array(moduleCount);
+ for (let row = 0; row < moduleCount; row += 1) {
+ modules[row] = new Array(moduleCount);
+ for (let col = 0; col < moduleCount; col += 1) {
+ modules[row][col] = null;
+ }
+ }
+ return modules;
+ })(_moduleCount);
+ setupPositionProbePattern(0, 0);
+ setupPositionProbePattern(_moduleCount - 7, 0);
+ setupPositionProbePattern(0, _moduleCount - 7);
+ setupPositionAdjustPattern();
+ setupTimingPattern();
+ setupTypeInfo(test, maskPattern);
+ if (_typeNumber >= 7) {
+ setupTypeNumber(test);
+ }
+ if (_dataCache == null) {
+ _dataCache = createData(_typeNumber, _errorCorrectionLevel, _dataList);
+ }
+ mapData(_dataCache, maskPattern);
+ };
+ const setupPositionProbePattern = function(row, col) {
+ for (let r = -1; r <= 7; r += 1) {
+ if (row + r <= -1 || _moduleCount <= row + r) continue;
+ for (let c = -1; c <= 7; c += 1) {
+ if (col + c <= -1 || _moduleCount <= col + c) continue;
+ if (0 <= r && r <= 6 && (c == 0 || c == 6) || 0 <= c && c <= 6 && (r == 0 || r == 6) || 2 <= r && r <= 4 && 2 <= c && c <= 4) {
+ _modules[row + r][col + c] = true;
+ } else {
+ _modules[row + r][col + c] = false;
+ }
+ }
+ }
+ };
+ const getBestMaskPattern = function() {
+ let minLostPoint = 0;
+ let pattern = 0;
+ for (let i = 0; i < 8; i += 1) {
+ makeImpl(true, i);
+ const lostPoint = QRUtil.getLostPoint(_this);
+ if (i == 0 || minLostPoint > lostPoint) {
+ minLostPoint = lostPoint;
+ pattern = i;
+ }
+ }
+ return pattern;
+ };
+ const setupTimingPattern = function() {
+ for (let r = 8; r < _moduleCount - 8; r += 1) {
+ if (_modules[r][6] != null) {
+ continue;
+ }
+ _modules[r][6] = r % 2 == 0;
+ }
+ for (let c = 8; c < _moduleCount - 8; c += 1) {
+ if (_modules[6][c] != null) {
+ continue;
+ }
+ _modules[6][c] = c % 2 == 0;
+ }
+ };
+ const setupPositionAdjustPattern = function() {
+ const pos = QRUtil.getPatternPosition(_typeNumber);
+ for (let i = 0; i < pos.length; i += 1) {
+ for (let j = 0; j < pos.length; j += 1) {
+ const row = pos[i];
+ const col = pos[j];
+ if (_modules[row][col] != null) {
+ continue;
+ }
+ for (let r = -2; r <= 2; r += 1) {
+ for (let c = -2; c <= 2; c += 1) {
+ if (r == -2 || r == 2 || c == -2 || c == 2 || r == 0 && c == 0) {
+ _modules[row + r][col + c] = true;
+ } else {
+ _modules[row + r][col + c] = false;
+ }
+ }
+ }
+ }
+ }
+ };
+ const setupTypeNumber = function(test) {
+ const bits = QRUtil.getBCHTypeNumber(_typeNumber);
+ for (let i = 0; i < 18; i += 1) {
+ const mod = !test && (bits >> i & 1) == 1;
+ _modules[Math.floor(i / 3)][i % 3 + _moduleCount - 8 - 3] = mod;
+ }
+ for (let i = 0; i < 18; i += 1) {
+ const mod = !test && (bits >> i & 1) == 1;
+ _modules[i % 3 + _moduleCount - 8 - 3][Math.floor(i / 3)] = mod;
+ }
+ };
+ const setupTypeInfo = function(test, maskPattern) {
+ const data = _errorCorrectionLevel << 3 | maskPattern;
+ const bits = QRUtil.getBCHTypeInfo(data);
+ for (let i = 0; i < 15; i += 1) {
+ const mod = !test && (bits >> i & 1) == 1;
+ if (i < 6) {
+ _modules[i][8] = mod;
+ } else if (i < 8) {
+ _modules[i + 1][8] = mod;
+ } else {
+ _modules[_moduleCount - 15 + i][8] = mod;
+ }
+ }
+ for (let i = 0; i < 15; i += 1) {
+ const mod = !test && (bits >> i & 1) == 1;
+ if (i < 8) {
+ _modules[8][_moduleCount - i - 1] = mod;
+ } else if (i < 9) {
+ _modules[8][15 - i - 1 + 1] = mod;
+ } else {
+ _modules[8][15 - i - 1] = mod;
+ }
+ }
+ _modules[_moduleCount - 8][8] = !test;
+ };
+ const mapData = function(data, maskPattern) {
+ let inc = -1;
+ let row = _moduleCount - 1;
+ let bitIndex = 7;
+ let byteIndex = 0;
+ const maskFunc = QRUtil.getMaskFunction(maskPattern);
+ for (let col = _moduleCount - 1; col > 0; col -= 2) {
+ if (col == 6) col -= 1;
+ while (true) {
+ for (let c = 0; c < 2; c += 1) {
+ if (_modules[row][col - c] == null) {
+ let dark = false;
+ if (byteIndex < data.length) {
+ dark = (data[byteIndex] >>> bitIndex & 1) == 1;
+ }
+ const mask = maskFunc(row, col - c);
+ if (mask) {
+ dark = !dark;
+ }
+ _modules[row][col - c] = dark;
+ bitIndex -= 1;
+ if (bitIndex == -1) {
+ byteIndex += 1;
+ bitIndex = 7;
+ }
+ }
+ }
+ row += inc;
+ if (row < 0 || _moduleCount <= row) {
+ row -= inc;
+ inc = -inc;
+ break;
+ }
+ }
+ }
+ };
+ const createBytes = function(buffer, rsBlocks) {
+ let offset = 0;
+ let maxDcCount = 0;
+ let maxEcCount = 0;
+ const dcdata = new Array(rsBlocks.length);
+ const ecdata = new Array(rsBlocks.length);
+ for (let r = 0; r < rsBlocks.length; r += 1) {
+ const dcCount = rsBlocks[r].dataCount;
+ const ecCount = rsBlocks[r].totalCount - dcCount;
+ maxDcCount = Math.max(maxDcCount, dcCount);
+ maxEcCount = Math.max(maxEcCount, ecCount);
+ dcdata[r] = new Array(dcCount);
+ for (let i = 0; i < dcdata[r].length; i += 1) {
+ dcdata[r][i] = 255 & buffer.getBuffer()[i + offset];
+ }
+ offset += dcCount;
+ const rsPoly = QRUtil.getErrorCorrectPolynomial(ecCount);
+ const rawPoly = qrPolynomial(dcdata[r], rsPoly.getLength() - 1);
+ const modPoly = rawPoly.mod(rsPoly);
+ ecdata[r] = new Array(rsPoly.getLength() - 1);
+ for (let i = 0; i < ecdata[r].length; i += 1) {
+ const modIndex = i + modPoly.getLength() - ecdata[r].length;
+ ecdata[r][i] = modIndex >= 0 ? modPoly.getAt(modIndex) : 0;
+ }
+ }
+ let totalCodeCount = 0;
+ for (let i = 0; i < rsBlocks.length; i += 1) {
+ totalCodeCount += rsBlocks[i].totalCount;
+ }
+ const data = new Array(totalCodeCount);
+ let index = 0;
+ for (let i = 0; i < maxDcCount; i += 1) {
+ for (let r = 0; r < rsBlocks.length; r += 1) {
+ if (i < dcdata[r].length) {
+ data[index] = dcdata[r][i];
+ index += 1;
+ }
+ }
+ }
+ for (let i = 0; i < maxEcCount; i += 1) {
+ for (let r = 0; r < rsBlocks.length; r += 1) {
+ if (i < ecdata[r].length) {
+ data[index] = ecdata[r][i];
+ index += 1;
+ }
+ }
+ }
+ return data;
+ };
+ const createData = function(typeNumber2, errorCorrectionLevel2, dataList) {
+ const rsBlocks = QRRSBlock.getRSBlocks(typeNumber2, errorCorrectionLevel2);
+ const buffer = qrBitBuffer();
+ for (let i = 0; i < dataList.length; i += 1) {
+ const data = dataList[i];
+ buffer.put(data.getMode(), 4);
+ buffer.put(data.getLength(), QRUtil.getLengthInBits(data.getMode(), typeNumber2));
+ data.write(buffer);
+ }
+ let totalDataCount = 0;
+ for (let i = 0; i < rsBlocks.length; i += 1) {
+ totalDataCount += rsBlocks[i].dataCount;
+ }
+ if (buffer.getLengthInBits() > totalDataCount * 8) {
+ throw "code length overflow. (" + buffer.getLengthInBits() + ">" + totalDataCount * 8 + ")";
+ }
+ if (buffer.getLengthInBits() + 4 <= totalDataCount * 8) {
+ buffer.put(0, 4);
+ }
+ while (buffer.getLengthInBits() % 8 != 0) {
+ buffer.putBit(false);
+ }
+ while (true) {
+ if (buffer.getLengthInBits() >= totalDataCount * 8) {
+ break;
+ }
+ buffer.put(PAD0, 8);
+ if (buffer.getLengthInBits() >= totalDataCount * 8) {
+ break;
+ }
+ buffer.put(PAD1, 8);
+ }
+ return createBytes(buffer, rsBlocks);
+ };
+ _this.addData = function(data, mode) {
+ mode = mode || "Byte";
+ let newData = null;
+ switch (mode) {
+ case "Numeric":
+ newData = qrNumber(data);
+ break;
+ case "Alphanumeric":
+ newData = qrAlphaNum(data);
+ break;
+ case "Byte":
+ newData = qr8BitByte(data);
+ break;
+ case "Kanji":
+ newData = qrKanji(data);
+ break;
+ default:
+ throw "mode:" + mode;
+ }
+ _dataList.push(newData);
+ _dataCache = null;
+ };
+ _this.isDark = function(row, col) {
+ if (row < 0 || _moduleCount <= row || col < 0 || _moduleCount <= col) {
+ throw row + "," + col;
+ }
+ return _modules[row][col];
+ };
+ _this.getModuleCount = function() {
+ return _moduleCount;
+ };
+ _this.make = function() {
+ if (_typeNumber < 1) {
+ let typeNumber2 = 1;
+ for (; typeNumber2 < 40; typeNumber2++) {
+ const rsBlocks = QRRSBlock.getRSBlocks(typeNumber2, _errorCorrectionLevel);
+ const buffer = qrBitBuffer();
+ for (let i = 0; i < _dataList.length; i++) {
+ const data = _dataList[i];
+ buffer.put(data.getMode(), 4);
+ buffer.put(data.getLength(), QRUtil.getLengthInBits(data.getMode(), typeNumber2));
+ data.write(buffer);
+ }
+ let totalDataCount = 0;
+ for (let i = 0; i < rsBlocks.length; i++) {
+ totalDataCount += rsBlocks[i].dataCount;
+ }
+ if (buffer.getLengthInBits() <= totalDataCount * 8) {
+ break;
+ }
+ }
+ _typeNumber = typeNumber2;
+ }
+ makeImpl(false, getBestMaskPattern());
+ };
+ _this.createTableTag = function(cellSize, margin) {
+ cellSize = cellSize || 2;
+ margin = typeof margin == "undefined" ? cellSize * 4 : margin;
+ let qrHtml = "";
+ qrHtml += '