Question

Draw equipotential surfaces:

(1) in the case of a single point charge and

(2) in a constant electric field in Z-direction. Why are the equipotential surfaces about a single charge not equidistant?

(3) Can electric field exist tangential to an equipotential surface? Give reason

Answer 1

(1)

(2)

The equipotential surfaces about a single charge are not equidistant because electric field due to a single change is not constant.

(3) If the electric field exist along tangential to an equipotential surface, a charged particle will experience a force along the tangential line and can move along it. As a charged particle can move only due to the potential difference (along with the direction of change of potential), this contradicts the concept of an equipotential surface.