# How will electrons flow in a very long conductor?

erocored
I have two charged spheres connected to different ends of an infinitely long conductor. The first sphere has positive charge, another sphere has negative charge. Suppose that the electric field of the first sphere at point A is zero, and the electric field of the second sphere is zero at point B. Will be any current in this conductor?

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An infinitely long conductor has no ends.

erocored
An infinitely long conductor has no ends.
I mean two spheres are so distant that their electric fields do not interact

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I mean two spheres are so distant that their electric fields do not interact
You still must have an electric potential difference. And interaction between the charges in the conductor and the spheres at either end.

erocored
You still must have an electric potential difference.
Then what will move electrons through the segment AB?

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Then what will move electrons through the segment AB?
The electric field is never zero for either sphere.

Are the spheres insulators or conductors themselves?

erocored
The electric field is never zero for either sphere.

Are the spheres insulators or conductors themselves?
spheres are conductors. Is this almost zero electric field enough to move electrons?

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spheres are conductors. Is this almost zero electric field enough to move electrons?
Electrons at one end of the conductor will be drained off to neutralise the positive charge; and the excess electrons on the negative sphere will drain into the conductor. Just as you should expect.

vanhees71 and erocored
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spheres are conductors. Is this almost zero electric field enough to move electrons?
The flow of electrons is proportional to the strength of the electric field across the conductor. There is no deadband or hysteresis.

The tricky thing about you scenario is that as soon as some current flows, the charge difference between the spheres will reduce and decrease the electric field. The charges will quickly balance and the current will stop flowing.

vanhees71 and erocored