A point charge is surrounded symmetrically by six identical charges at distance `r` as shown in the figure How much work is done by the froces of electrostatic repulsion when the point charge at the centre is removed to infinity ?

Options

A. Zero
B. `6q^2//4piepsilon_0r`
C. `q^2//4piepsilon_0r`
D. `12q^2//4piepsilon_0r`

Answer

B

Explanation

`U_i =(6q^2)/(4piepsilon_0r)=qV_0=q(6/(4piepsilon_0r).q/r)`
`U_f=0`
`|W|=U_f-U_i|=(6q^2)/(4piepsilon_0r)`