Define an equipotential surface.

Show that the direction of electric field at a given is normal to the equipotential surface passing through that point.

The angle between the electric lines of force and the equipotential surface is

The equation of an equipotential line in an electric field is $y = 2x$, then the electric field strength vector at $(1, 2)$ may be

Thepoints resembling equal potentials are

Given below are two statements: one is labelled a

Assertion $(A)$ and the other is labelled as Reason$(R)$

$Assertion$ $(A)$ : Work done by electric field on moving a positive charge on an equipotential surface is always zero.

$Reason$ $(R)$ : Electric lines of forces are always perpendicular to equipotential surfaces.

In the light of the above statements, choose the most appropriate answer from the options given below