Question

Consider a uniform horizontal electric field of 50 N/C directed toward the east. If the electric potential measured at a given point is 80 V, what is the
potential at a point 1.0 m directly west of that point?

Answer 1

Electric field = $\frac {-dV} {dx}$

So electric potential decrease in the direction of EF

$50 = \frac {(v - 80)} {1}$

V = 130 V

So the potential west of that point will be 130 V