If identical charges `(-q)` are placed at each corner of a cube of side `b`, then electric potential energy of charge `(+q)` which is palced at centre of the cube will be

Options

A. `(8sqrt(2) q^(2))/(4 pi epsilon_(0) b)`
B. `(-8sqrt(2) q^(2))/(pi epsilon_(0) b)`
C. `(-4 sqrt(2) q^(2))/(pi epsilon_(0) b)`
D. `(-4 q^(2))/(sqrt(3) pi epsilon_(0) b)`

Answer

4

Explanation

Number of pairs `= 8`
`U = (1)/(4 pi in_(0)) .(-q*q)/((sqrt(3) b//2)) xx 8 = (-4q^(2))/(sqrt(3) pi in_(0) b)`