The electric field at point P just outside the outer surface of a hollow spherical conductor of inner radius 11 cm and outer radius 32 cm has magnitude 475 N/C and is directed outward. When an unknown point charge Q is introduced into the center of the sphere, the electric field at P is still directed outward but is now 212 N/C.
(a) What was the net charge enclosed by the outer surface before Q was introduced? (b) What is charge Q ? After Q is introduced, what is the charge on the (c) inner and (d) outer surface of the conductor? Give answers in nC.