Electric Field in Conductor: Why Does it Become Zero Inside?

When charges mutually repel and distribute themselves on the surface of conductors, what happens to the electric field inside the conductor?

What happens to the electric field inside the conductor when charges arrange themselves on the surface? Is it zero, radially symmetric, or a non-zero value everywhere?

Answer:

When charges mutually repel and distribute themselves on a conductor's surface, the electric field inside the conductor becomes zero.

When charges mutually repel and distribute themselves on the surface of conductors, the electric field inside the conductor becomes zero. This is achieved through an electrostatic equilibrium wherein excess charges repel each other and move until they are uniformly distributed on the surface of the conductor. This force to the surface continues until there is no electric field present within the conductor.

For instance, consider a spherical conductor with an excess positive charge. The repulsion of these excess positive charges distributes them uniformly on the surface of the conductor, resulting in an electric field that is perpendicular to the surface and zero inside. Outside the conductor, the resulting field is identical to that of a point charge situated at the center equal to the excess charge.

In the instance of a conductor with two cavities, differing charges within each cavity polarize the conductor resulting in differing charges on the internal and external surfaces of the cavities. Upon reaching equilibrium, the distribution of charge within a conductor creates an electric field that cancels out the external electric field within the body of the conductor.

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