Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

3. The surface of a charged conductor is equipotential.

Explanation:
In conductors, charges are equally distributed over the surface of the conductor. Therefore the potential throughout the surface is the same, i.e. equipotential. The electric field is a vector quantity and the field lines cut the equipotential surfaces at 90 degrees. The field lines due to a point charge are radial.