The electric potential decreases uniformly from 180V to 20V as one moves on the X-axis from `x=-2cm ` to `x= +2cm`. The electric field at the origin:

Options

A. must be equal to 40 V/cm
B. may be equal to 40 V/cm
C. may be less than 30 V/m
D. may be less than 40 V/cm

Answer

B

Explanation

from given data `E_(x)=160/4 V//cm =40 V//cm`
but E`=sqrt(E_(x)^(2)+E_(y)^(2)+E_(z)^(2)) rArr ` E may be equal or greater than 40 V/cm ie.

As shown, there can be electric fields `bot` to x axis, which will not affect the electric potential difference but can increase net field.