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by lamontcg 1650 days ago
The problem is that his video is a mish-mash of two different concepts that were taught perfectly well in my freshman physics course. One is that the electric field travels down a wire at the speed of light while the electrons do not. The other is induced currents by moving charges.

I got the answer "wrong" by watching the video because I didn't consider the tiny amount of current induced in the other wire to be sufficient to turn on the light in any useful manner. If you had replaced the light with a sensitive ammeter and asked me what the first point in time there would be any measurable deflection from zero, then I would have gotten it correct.

Could have also just asked how this works, and the success rate would have gone way up (but he'd have lost all his clickbait):

https://www.amazon.com/Fluke-324-Temperature-Capacitance-Mea...

Ask bad questions, get bad answers. Nothing wrong with how physics/EE is taught.

1 comments

This is exactly it. If being "right" or "wrong" about something involves subjective facts (is the lamp "lit" by the small amount of electricity induced by cosmic rays too?!?!) and trying to visually inspect an experiment you can't access in-person, then the only thing "wrong" is the video maker.
"Communicating badly and then acting smug when you're misunderstood" https://xkcd.com/169/
Let's not forget that Derek's PhD thesis was about the practice of making videos that dunk on unsuspecting members of the general public.
I don't think there is any need to be snarky here.

Link to his PhD thesis (PDF) - https://www.sydney.edu.au/science/physics/pdfs/research/supe...

I'm not being snarky, the formula of his videos at the time was 1) Ask somebody in a public park a science question. 2) They get it wrong. 3) Explain why they're wrong. His thesis was about the supposed efficacy of this style of video (which he has since moved on from, to his credit.)