Why cant there be an electric field in a conductor?

AI Thread Summary
An electric field cannot exist within a conductor at equilibrium because the fields from opposite sides cancel each other out, resulting in a net electric field of zero. If the conductor is not at equilibrium, such as when a voltage or current source is applied, the electric field becomes non-zero, allowing charge carriers to move. This movement disrupts equilibrium, indicating that an external force is acting on the charges. The relationship between the electric field and current in this scenario is described by Ohm's law. Understanding these principles is essential for analyzing electrical circuits and conductor behavior.
indigojoker
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why can't there be an electric field in a conductor?
 
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Because Maxwell said so!
Short answer is that the fields from each side of a point inside the conductor cancel out - long answer involves a bit of maths.
 
I guess you are talking about a conductor at equilibrium. In this case the electric field in the conductor is 0 because otherwise the charge (which is mobile in a conductor) would be moving and there wouldn't be equilibrium any more.
 
I guess you are talking about a conductor at equilibrium.

what other cases are there and why would there be an electric field in the conductor?
 
indigojoker said:
what other cases are there and why would there be an electric field in the conductor?

If there is a net force acting on the charge carriers, the conductor isn't at equilibrium any more. This force could come from a voltage/current source or from a change in the magnetic flux in that circuit.
In this case the electric field in that conductor isn't 0 any more. It is given by Ohm's[/PLAIN] law
 
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