A solid conducting sphere of radius r is having a charge of Q and point charge q is a distance d from the centre of sphere as shown. The electric potential at the centre of the solid sphere is :

Options

A. `(1)/(4 pi in_(0))[(Q -q)/(r) + (q)/(d)]`
B. `(1)/( 4pi in_(0))[(Q)/(r) + (Q-q)/(d)]`
C. `(1)/(4 pi in_(0))[(Q)/(r) + (q)/(d)]`
D. Zero

Answer

C

Explanation

`V=Q/(4 pi e_0 r) +q/(4 pi e_0 d)`