Conductors

A conductor with excess charge carriers all at rest (no currents) is said to be in electrostatic equilibrium. Conductors in electrostatic equilibrium have the following properties (which you should be able to demonstrate):

The electric field inside the conductor is zero everywhere, regardless of any excess or nearby electric charge.
Any excess charge placed on the conductor resides entirely on its surface.
The electric field just outside the conductor’s surface is perpendicular to that surface with magnitude equal to s/e₀ , where s is the charge per unit area at that point.
On an irregularly shaped conductor, charge tends to accumulate at sharp points and move away from valleys.