a spherical shell of radius 'a' with charge Q is expanded to radius 'b' . find the work done by electrical force in the process?
in this ques.why we use the relation w=12 VQ.....instead of W=VQ?
the work done would be given as
W = Q(VB - VA)
here,
VA = kQ/a
and
VB = kQ/b
so,
W = Q.[(kQ/b) - (kQ/a)]
thus,
W = kQ2.[(1/b) - (1/a)]