The variation of potential with distance R from a fixed point is as shown in figure.

the electric field at R = 5 m is $\left(\frac{4}{5}\right)$ V-m-1 the electric field at R = 5 m is $\left(\frac{4}{5}\right)$ V-m+1 the potential at R = 5m is +2.5 V-m–1 is continuous and a decreasing function of distance. the segment AB corresponds to an equipotent surface.

the segment AB corresponds to an equipotent surface.

The segment AB corresponding to an equipotential surface.