Consider a uniform electric field in the `hat (z)` direction. The potential is a constant.

Options

A. in all space
B. for any x for a given z
C. for any y for a given z
D. on the x-y plane for given z

Answer

B, C, D

Explanation

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Here, the figure electric field is always remain in the direction in which the potential decreases steepest. Its magnitude is given by the change in the magnitude of potential per unit displacement normal to the equipotential surface at the point.
The electric field in z-direction suggest that equipotential surfaces are in x-y plane. therefore the potential is a constant for any x for a given z , for any y for a given z and on the x-y plane for a given z.