41–48 of 48 posts
Earlier quoted context omitted.
I used to use the scene in "the two towers" where they light the fire to let Rohan know that Gondor is in need of aid. I thinks I have to stop referencing Lord of the Rings because most high schoolers haven't seen the movie these days. https://www.youtube.com/results?search_query=beacons+of+mina...
At least you aren't referencing the Twilight Bark from 101 Dalmatians - https://www.youtube.com/watch?v=xp-DW-2bq2U .
I teach high school physics. Here's my notes/textbook on electricity with simulations and equations rendered in LaTex. https://landgreen.github.io/physics/notes/circuits/electrici...
Awesome notes. I haven't had my coffee yet so perhaps I'm just misreading this part: "In 1746 Benjamin Franklin mistakenly assigned a negative value to the charge carriers that we now call electrons." Shouldn't that read "mistakenly assigned a _positive_ value to the charge carriers that we now call electrons"?
Earlier quoted context omitted.
But existing theory predicts all those just fine, it just happens that some things are not in the same direction, but it’s not like one can ignore direction. The math is still always there. And I argue things going in different directions is a feature, not a bug, because it reinforces the point that net charge and net particles are not the same thing.
Right, the math is the same. We face this in physics all the time. You drop a ball and it accelerates downward. Should the distance it covers be a negative number? Well, it seems linear distance should be positive, but if it is, then does down become positive? Shouldn't up be positive? Or do we reverse from end-minus-start and make it start-minus-end? It doesn't matter. The math is all the same with just different la…
The classic, and really intuitive, experiment that requires one to understand the movement of both the carriers and the charge at the same time is the Haynes Shockley experiment [1]. It has not been my experience that charge convention gets in the way of students interpreting this experiment.
For the vast majority of practical (artificial?) electronics, when designing one only needs to look at the movement of net charge. Passive sign convention (used by spice) is about the flow of charge, not carriers. Maxwell's equations don't even mention the carriers. It's not clear to me why one needs to visualise carriers to design circuits. In my experience (i.e. transmission lines) it can actually hinder students to consider the movement of carriers when designing a practical circuit.
[1] https://en.wikipedia.org/wiki/Haynes–Shockley_experiment [2] https://en.wikipedia.org/wiki/Passive_sign_convention
It's interesting to me when I read it. We take it down to the proton neutron and electron stating they are charged with positive negative or neutral charge.... but what are they charged with ? Electricity ? What is it made of ?
It's made of the electromagnetic force. We can measure it and characterize it very accurately with mathematics. We can say what it isn't (gravity or the weak force or the strong force), but we cannot say what the electromagnetic force is . Sorry. If you figure it out you'll get a Nobel Prize.
Isn't the electric and the weak force considered the same force these days? See also https://en.m.wikipedia.org/wiki/Electroweak_interaction
Earlier quoted context omitted.
Right, the math is the same. We face this in physics all the time. You drop a ball and it accelerates downward. Should the distance it covers be a negative number? Well, it seems linear distance should be positive, but if it is, then does down become positive? Shouldn't up be positive? Or do we reverse from end-minus-start and make it start-minus-end? It doesn't matter. The math is all the same with just different la…
We're probably going to have to agree to disagree on this one as I just don't see the nuisance and I see some positive aspects to the existing convention which I highlighted previously. The classic, and really intuitive, experiment that requires one to understand the movement of both the carriers and the charge at the same time is the Haynes Shockley experiment [1]. It has not been my experience that charge conventio…
This is trivial for somebody who studies electrical engineering in highschool
One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how…
Here's my take on a cartoony conductivity simulation. I've got three models: conductors, semiconductors, and semiconductors but with holes. https://landgreen.github.io/physics/notes/electromagnetism/c...