Question

Four point charges (with equal magnitude of charge of 5 C; but with different signs) are
placed at four corners of a square of side 10 m. Assuming that the square is centered at the
origin and the configuration of the charges are as given in the figure, the potential and the
magnitude of electric field at the origin, respectively are
-
(A)0 V and 0 V/m
(B) 0 V and 5
V/m
(C) 5
Vand 5
kv/m
k
(D) O V and 5 V/m
(E) 5
V and 0 v/m​

Answer 1

Net electric field will be zero due to the symmetry and equal amount of charges at the corners.

As for net potential, calculate the distance between the origin and any one of the charges which is equal for all i.e 10/✔️2

V= k(20C/r)
= k(20Cx✔️2/10m)
=k10✔️2 V