
High school physics course notes, with JavaScript simulations - lilgreenland
https://landgreen.github.io/physics/index.html
======
lilgreenland
I just completed my two year project to build an online website to pair with
my 11th grade physics classes.

I hope it can be a resource for those learning and teaching physics. I've got
some free time this summer so let me know if you have any advice about what
else to add.

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danesparza
I'm curious about the Javascript simulations -- which lessons contains those
simulations? (I couldn't find any in the few lessons I looked at)

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worldsayshi
There's a few nice simulations on momentum here:
[https://landgreen.github.io/physics/notes/momentum/1-intro/i...](https://landgreen.github.io/physics/notes/momentum/1-intro/index.html)

And here on gravity:
[https://landgreen.github.io/physics/notes/gravity/gravitatio...](https://landgreen.github.io/physics/notes/gravity/gravitation/index.html)

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Arubis
I had outlandishly good access to a solid physics curriculum in high school,
because (a) I had a teacher who cared deeply about his students and (b) I
attended a new and well-funded charter school that had funds to throw at
materials.

For all that, our books were still, well, books: dry, static, and squinty-
small print.

This approach to teacher's notes (and the obvious care that went into it)
would've changed my approach to physics, to learning, and to life, and that's
coming from an uncommonly well-resourced background. I can't even imagine what
this would do for students with less access.

~~~
Waterluvian
Had the same thing at my public school. The physics teacher was a physics prof
who wanted to do something more chill during the back 9 of his life.

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furgooswft13
As far as physics simulations go, this is my favorite treasure trove:

[http://www.falstad.com/mathphysics.html](http://www.falstad.com/mathphysics.html)

Ripple Tank and Analog Circuit Simulator are my favs. I could play for days.

~~~
virgil_disgr4ce
THIS THIS THIS!! This guy boggles my mind. I've used his simulations in every
class I've taught, and my students are just as impressed as I am.

I owe this guy about 1000 beers. Seriously, I would love to meet him so I can
thank him personally.

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pickle-ts
I love this kind of stuff - just a bit envious I didn't have these kind of
resources when I was a kid! Javascript simulations are easy to write, and help
enormously with visualization. Here's a special relativity simulation I wrote
in ~100 lines of code:

[http://pickle-ts.com/relativity](http://pickle-ts.com/relativity)

Source code you can play with live: [https://stackblitz.com/edit/pickle-
samples?file=app%2Frelati...](https://stackblitz.com/edit/pickle-
samples?file=app%2Frelativity.ts)

~~~
lilgreenland
Cool!

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hliyan
The best online physics resource I ever used was from over fifteen years ago.
Looking at it now, I feel that the old hypercard format has aged well:
[http://hyperphysics.phy-
astr.gsu.edu/hbase/hframe.html](http://hyperphysics.phy-
astr.gsu.edu/hbase/hframe.html)

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cproctor
Congratulations! These look really nice! If you wanted to make them more
useful and inspiring to other teachers, it would be wonderful to pair them
with an essay on how they can be used effectively in class. Do students use
them to explore, like microworlds? Do you use them during classroom
discussions, for posing hypotheses or consolidating several ideas? Do students
use them as evidence during debates? Do students get used to having these and
think up others they wish they had? Do they become touchstones students use to
remind themselves of something they previously understood?

Supporting social practices is an important part of a technology--folks
without experience in schools (or informal learning environments) sometimes
picture educational technologies being used alone in a vacuum, the mooc high
school. I'm pretty hopeful about using educational technologies to help
teachers grow their teaching practices.

~~~
lilgreenland
Good idea, I'll add in a section for teachers over the summer. I might link to
some of the labs and worksheets.

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VectorLock
I love the circuit simulation that shows the field. I've never seen that
before and its super neat. Its cool how you can see what looks like random
electrons occasionally flying off and coming in from outside the 'wires' as
well.

~~~
lilgreenland
That's my favorite simulation so far, but I also like the one on wave
propagation.

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s0ulphire
> Light seems like it slows down in dense media, but light always propagates
> at the fastest possible speed for any physical thing. The slow down occurs
> when the light gets briefly absorbed by atoms and then re-emitted in the
> same direction.

Someone please correct me if I'm wrong, but Sixty Symbols (aka
nottinghamscience) did at least 2 videos on this where they expressly pointed
out that this is widely pushed but totally incorrect?
[https://www.youtube.com/watch?v=CiHN0ZWE5bk](https://www.youtube.com/watch?v=CiHN0ZWE5bk)

~~~
lilgreenland
thanks! When I wrote that line I think I went with the top result of
physics.stackexchange, but I'm now convinced that the phase velocity
explanation is better.

Here is my updated text:

<p>While individual waves of light always move at c, light seems to move
slower in dense media. This is because as the light wave propagates through a
medium it produces ripples that <a
href="[https://www.youtube.com/watch?v=CiHN0ZWE5bk">interfere</a>](https://www.youtube.com/watch?v=CiHN0ZWE5bk">interfere</a>)
in a way that slows the group velocity of the light wave.</p>

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mncharity
> We are going to focus on the two types of dry friction: static and kinetic.

"dry friction"... As I remember the story, someone was trying to replicate
Arrheniius's equipment and results. The results weren't matching, until they
took the equipment to an outreach event... where it got covered with greasy
fingerprints. Turns out, it's Arrheniius's law of large objects sliding on pig
fat.

We actually now understand friction down to nanoscale. Something that wasn't
true a decade ago. But I've never seen introductory friction content written
to reflect that.

~~~
lilgreenland
I'm not that knowledgeable on friction. Do you think the friction equations
are OK for high school level physics?

Would you say that this is accurate?

"Kinetic friction is primarily caused by chemical bonding between surfaces;
however, in many cases roughness is dominant."

~~~
mncharity
My very fuzzy impression is HS friction is more roughness and debris than
adhesion?[1]

[1] "Bridging from Atomic Forces to Macroscopic Friction"
[http://online.kitp.ucsb.edu/online/suspensions-c18/robbins/](http://online.kitp.ucsb.edu/online/suspensions-c18/robbins/)
. And the preceding "Contact of rough solids"
[http://online.kitp.ucsb.edu/online/suspensions18/robbins/](http://online.kitp.ucsb.edu/online/suspensions18/robbins/)
. Robbins also has an old 2004 AJP article "Understanding and illustrating the
atomic origins of friction"
[http://dx.doi.org/10.1119/1.1715107](http://dx.doi.org/10.1119/1.1715107) ,
but I've not skimmed it, nor explored its cited-bys for something similar but
more recent.

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bluedino
Somewhat simple stuff like this is the real reason classrooms should have
computers or iPads - not the wasteful resources and clunky programs they
actually get used for

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mncharity
Perhaps take screenshots of your favorite interactives, and add them to a new
"Highlights" section of the landing page? To guard against people stopping by,
randomly sampling a few pages, and by chance, missing interesting ones, and
thus giving up and going away, not knowing they missed fun things. Sort of
like the extract of figures from a paper - something to trigger "oh, _that_
looks interesting".

~~~
lilgreenland
That's a good idea. My current solution is to just try and make every page
awesome, but I know some sections have more love than others.

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anonnel
Very cool. Where’s the patreon link!

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emumoo
Here's another great resource for physics simulations

[http://galileoandeinstein.physics.virginia.edu/more_stuff/Ap...](http://galileoandeinstein.physics.virginia.edu/more_stuff/Applets/home.html)

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Edmond
nice...have you considered PHET syms
([https://phet.colorado.edu/](https://phet.colorado.edu/))?

I also built a CMS-type environment for this type of content. It combines
content creation with an IDE to create simulations that can be combined with
the content.

Here is a static and old version of the software:
[http://schoolnotez.com/](http://schoolnotez.com/)

There are folks interested in creating these types of interactive learning
environments, unfortunately it doesn't appear that there is much demand for it
by schools.

~~~
psalminen
Was going to mention PHET myself. These simulations were amazing when I was
studying physics at CU.

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kajecounterhack
The practice question generation is awesome. Wish I had this in high school.

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partycoder
Looks didactic and polished. Congratulations.

Now, I think this should be a "Show HN" entry.

If I was to implement something like this I would try to make use of Jupyter
or R with Shiny.

~~~
lilgreenland
If I had to do it over a Jupyter notebook might be cool. It would make the
graphing and equations easier. Although, I think simulation graphics are
probably better with html5 js canvas.

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Exuma
Hmm.. I feel crazy but... is that how atom nucleus' work??? Why does the
charge completely "exit" the atom? WTF?

~~~
lilgreenland
My Coulomb's law simulation is classical only, no quantum physics. I hope it
has some value in showing emergent phenomena.

Electrons can just leave the atom, this is how static electricity works.

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Exuma
Something so obvious I guess I never realized. So when electricity moves, the
nucleus stays still, and the electrons are what move?

~~~
lilgreenland
Hey my sims worked! You got it, although I'd add in that only the free
electrons can move around like the ones in the outer valence of metals.

~~~
Exuma
Damn, well... thats really wild. I feel stupid now, but yes, that absolutely
made it click.

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MaxLeiter
I just took AP Physics and this looks like it would have been very useful.
Will pass on to my teacher. Nice work!

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misrab
what's used to render the latex?

I used to use mathjax but I'm not sure if that's the case here

~~~
lilgreenland
I tried MathJax, but it added a half second render time, Katex loaded
instantly.

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reuseman
Quality.

~~~
lilgreenland
:)

