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Suppose an external wire of length 10^8 meter (very long indeed) is connected in between the slip rings of an AC generator externally. Taking the speed of current propagation to be ~10^7 m/s, then it takes 10 seconds for current to flow from one end of the wire to the other.
Now suppose the frequency of the AC generator is 10Hz.How would the current in the wire flow?
(To elaborate I need to say, external load is midway between the close loop of external wires. And the electrons need at least 5 seconds to reach load once the rectangular coil is rotated in a magnetic field. It seems electrons fail to reach load even after complete rotation of coil, thereby leaving an impression of colliding of electrons in the midway between the external load and any of the slip rings.)
It's difficult to explain this question in further simple words. I expect some guy with good imagination skills would understand the question and come up with a reasonable answer.
Thank you.

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    $\begingroup$ It's difficult to imagine a situation such as this one as it is not the case we observe in our everyday life. $\endgroup$ Jul 15, 2016 at 12:52
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    $\begingroup$ But its clear explanation certainly needs a little thinking. $\endgroup$ Jul 15, 2016 at 12:54

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In this case I expect the electrons move in the long wire exactly like the waves or ripples of water throughout the length of the river.

I imagine the electron density changing along the wires similar to the peak of waves. There will be time varying regions of high densities and low densities. The frequency of that changes match that of the generator.

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  • $\begingroup$ +1 - it looks like wave propagation is the correct model for this hypothetical. $\endgroup$
    – feetwet
    Feb 24, 2016 at 14:45
  • $\begingroup$ I believe that too... $\endgroup$ Feb 24, 2016 at 14:54