Question

Four charges of `6 muC,2muC,-12muC and 4 muC` are placed at the corners of a square of side 1m. The square is in x-y plane and its centre is at origin. Electric potential due to these charges is zero everywhere or the line
A. `x=y,z=0`
B. `z=0=z`
C. `x=0=y`
D. `x=z,y=0`

Answer 1

Correct Answer - C

Answer 2

As Sum of all the charges is zero, so the sum of potentials at one point will be zero if it is equidistant from all the edges of the sqaure. All point on the axis passing through the center of the sqaure are equidistant from all the corners and hence in this question the Z-axis 

which can be represented as x=0=y (C)