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A comment on Activists who embrace nuclear power. Parent comment

Re:Activists who embrace nuclear power by Ono-Sendai on Sunday February 21, 2021 @09:44PM (#26220210)
I don't think you are correct. For electricity to propagate at near light speed, electrons will have to move at near light speed, if only for a short time. Or to be a little more precise, shape changes in the electron wavefunction will need to propagate at near light speed. I think we can do this to electrons because their mass is so low.

This only really applies when a circuit is opened or closed however. Once a circuit reaches a stable state (voltage is unchanged) the electrons don't move fast, I guess.

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Re:Activists who embrace nuclear power by StillBored on Monday February 22, 2021 @03:52PM (#26230439)
No, he is correct, its the wave that propagates at a fraction of the speed of light (depending on the conductor). The electrons themselves don't move very fast.

"An electron travels at a speed of about 1 cm/sec. " (in copper) per: https://www.informit.com/articles/article.aspx?p=2916283&seq...

This should be taught in a basic AP physics class in HS (where i initially heard it). I vaguely remember doing some of these calculations in my physics for engineers class as a first year engineering student too.

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Re:Activists who embrace nuclear power by Ono-Sendai on Monday February 22, 2021 @06:52PM (#26232223)
That article is probably wrong too. A changed electric field requires a change in the position of electrons. Hence a fast signal change requires fast position changes.
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