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Alternating current has a small drift velocity which periodically reverses: in other words, electrons move back and forth a small distance. Unless I'm missing something, the electromagnetic force would need to "fight against" the inertia of the electrons to reverse the direction of their movement, for which there would be no need with direct current.

This doesn't seem to be a problem at all in the real world, and as far as I understand this is due to the fact that the force needed to overcome this inertia is negligible compared to the electromagnetic force applied to the electrons (since the electromagnetic force is many orders of magnitude stronger in general between two electrons).

Is my reasoning correct?

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  • $\begingroup$ Pretty much correct. An electron is very light. Protons and neutrons are about 1800 times heavier. And electric forces are very strong. $\endgroup$
    – mmesser314
    Dec 29 '20 at 15:41
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    $\begingroup$ I would expect that electron inertia acts a lot like inductance. And inductance is already a thing $\endgroup$
    – user253751
    Dec 29 '20 at 15:43
  • $\begingroup$ Inductance comes from magnetic forces. Also pretty strong. $\endgroup$
    – mmesser314
    Dec 29 '20 at 15:44
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    $\begingroup$ see physics.stackexchange.com/questions/405349/… $\endgroup$
    – lamplamp
    Dec 29 '20 at 17:20
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    $\begingroup$ and see physics.stackexchange.com/questions/404937/… $\endgroup$
    – lamplamp
    Dec 29 '20 at 17:21
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Electrons in motion produce a magnetic field, which requires work to create. When the electrons stop moving, the field collapses and the work used to build it is returned to the electrons in a way that urges them to keep moving. This makes electrons act as if they had electrical "inertia". A straight wire has only a slight tendency to exhibit this effect (called inductance) but when you coil it up into a series of adjacent loops, the inductance becomes greatly magnified and the electrons seem to exhibit lots of "inertia".

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