(a) Inside a charged hollow metal sphere, electric field
(E) is zero but electric potential
(V) is not zero and equal to same potential as on its surface.
Work done to move a charge particle (either
+ve or -ve) on a equipotential surface between any two points is always zero.
Since,
W=q(V1−V2) ‌=q(V−V)‌‌(∵V1=V2=V)‌=0 Potential energy of system of two like charges placed at a distance
r is given as,
U=‌‌ When both like charges
q1 and
q2 are brought closer, then
r decreases, hence potential energy
U increases.
Therefore, statements (A), (B) and (C), all are true.