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Where does energy come from?

If a light bulb is connected to a generator 186,000 miles away, it will take one second before the bulb lights up. (Hint: speed of light) But, electrons, the supposed carrier of current and energy, only move 23 micro-meters per second.  

So, where does the energy come from that lights the bulb? The electrons only moved 23 micro-meters. So how did the energy get into the light bulb?

Should we redefine current flow? Can this be answered without dragging Mr. Poynting into the discussion?

Thanks for your consideration,

Cheers,

Toby

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  • $\begingroup$ Have you wondered about sound traveling soon fast in air? $\endgroup$ Feb 4 '18 at 1:04
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It is not the electron being sent from the generator that reaches the light bulb. It only pushes on its neighbor, which pushes on the next and so on. Until the adjacent electrons move through the bulb filament. That "push" is moving - propagating - at near the speed of sound. The more packed and the more rigid the material, the faster that signal is propagating. Not the electrons themselves.

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