Show that electric field is always directed perpendicular to an equipotential surface.

Define equipotential surface.

Why electric lines of force are always perpendicular to the equipotential surface ? Explain.

Give two properties of equipotential surface.

Describe schematically the equipotential surfaces corrsponsing to a constant electric field in the z-direction, Use the concept that the equipotential surface is always normal to the direction of electric field.

The angle between electric line of force and equipotential surface is

Why the surface of an isolated charged conductor is an equipotential surface ?