A point charge +Q is placed at the center O of an uncharged hollow spherical conductor of inner radius 'a' and outer radius 'b'. Find the following:
(a) The magnitiude and sign of the charge induced on the inner and outer surface of the conducting shell.
(b) The magnitude of electric field vector at a distance
(i) r = \(\frac{a}{2}\), and
(ii) r = 2b, from the center of the shell.