Question

What would a tangential component of the electric field at a conductor's surface cause?

Options

• The electric field inside the conductor would become zero automatically.

• The conductor's surface charge density would become permittivity of free space.

• Charges on the surface would move along the surface.

• The cavity would acquire a charge.

Answer 1

A tangential field component would exert a force along the surface and make surface charges move. At equilibrium, the electric field is therefore perpendicular to the surface.