We have seen in Chapter 1 that for a uniformly charged spherical shell,
the electric field outside the shell is as if the entire charge is concentrated
at the centre Thus, the potential outside the shell is given by
0
1
4
q
V
r
ε
=
π
   (
)
r
≥R
[2 19(a)]
where q is the total charge on the shell and R its radius The electric field
inside the shell is zero