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Comment by mtVessel | Hacker News Reader

Wait, is that right? I thought that was one of those "lies to children". I mean, yes, the electrons move (er...drift), but I thought the important thing is that it's the charge that moves, not the electrons.

At least it's not just me that thinks the usual explanations are lacking.

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The charge and the electrons are the same thing (at least in a normal conductor). Both move very slowly. But energy moves through them very quickly (fluid analogy is helpful here: when you pump water into a full hose then water starts flowing out of the hose quickly even though it may take a long time for the water you just pumped in to exit. In electricity the difference is even more extreme).

Correct. In a related concept, I had a professor that explained it as a combination of electron flow in one direction, and "hole" [1] flow in the other. Either way of looking at it is valid.

[1] https://en.m.wikipedia.org/wiki/Electron_hole

edit: I'm not sure, on second thought, how far you can really go with that. Lightning clearly has directionality to it.

But lightning is where the gas has broken down, turning into plasma. Lightning is a growing conductor, like a motorized antenna on an oldschool car radio.

The growth of lightning is much like a growing metal dendrite-crystal.

Also, when lightning leaps rapidly upwards, the electrons INSIDE the lightning are flowing slowly downwards. The extending tip of a lightning-streamer is not an electric current, it's more like the moving tip of a growing fracture.

Right. This passage from TFA hits on that:

> ...mistaking the wave for the medium. Is "electricity" the electrons, or is it the wave of electron-flow, or is it energy that flows THROUGH a column of electrons. Think of how difficult it would be to understand sound waves and air pressure if we had just a single word that meant both "sound" and "wind" and "air."

Sound : AC (maybe? Not sure.)

Wind : DC

Air : conductor

I think in this analogy, sound is more like voltage in the sense that voltage is like pressure: it’s a measure of potential per electron or force per air molecule. And when you push on the electrons at one end of a wire, that pressure change rapidly propagates to the other end of the wire even without the electrons moving. Like the way sound doesn’t involve air molecules flowing from place to place but is a pressure wave.

Wind is like electrical current in the sense that you set up a pressure difference between one point and another, and then you open up a little path for the electrons/air molecules to flow through, then they will move along that path, and the amount of air molecules/electrons flowing past a point per second is the current/wind. That’s the analogy.

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