Question

Define the Equipotential surface. Can the Electric fields be tangential to the Equipotential surface?

Answer 1

Definition of the Equipotential surface:

The equipotential surface is the surface that has the constant value of the potential at all the points on the surface.

Reason:

If the electric field lines are tangential then, the work will be done in moving the charge on the surface which is against the theory of the equipotential surface.

Therefore, The Electric field can not be tangential to the equipotential surface.