[javajosh]

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 energy can flow with holes (which is quite counter-intuitive, I think). In terms of mental model, the ratio of holes to ambient electrons is sometimes useful to think about, as this is fundamental to computing current limits of conductors.

There is a diagram (an animated GIF) about half-way down that sort of implies the newton's cradle method of moving charge, but I don't like it because it's not clear enough. Also, I see current as more of a fixed cloud of valence electrons with holes moving through it - which is a very different intuition than what this diagram implies.

[lilgreenland]

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...

[javajosh]

Yes, that looks much closer to what I have in mind, although I also tend to think of electrons as not visible individually and doing this as part of a large cloud over a 3-D crystalline substrate.

[dreamcompiler]

I like these diagrams. Now I want to see what superconductivity looks like in your framework. An unimpeded stream of electrons flowing as if the red dots aren't even there?

[lilgreenland]

My simulation just runs classical physics (Coulomb's law + Newton's laws). It's missing any mechanism for super conductivity. Although, I could just turn off friction.

I think superconductivity means the electrons pair up and stop colliding through the Pauli exclusion principle. I didn't code any collisions, so maybe it's already modeling a crappy version of superconductivity!

[nixpulvis]

The distinction is between the speed of propagation (e.g. how fast between a light switch flipping until lighting the room) and the physical movement of subatomic particles through the wire.

https://en.m.wikipedia.org/wiki/Drift_velocity

[Koshkin]

Looks like what you are describing is a model of the conductivity in the valence band (of a semiconductor). In the conduction band of a metal electrons move freely, their forward mobility being impeded only by heat.

[javajosh]

Well, maybe the part about the holes. But even wikipedia mentions newton's cradle! https://en.wikipedia.org/wiki/Electrical_resistivity_and_con...