A solid insulating sphere of radius a = 5 cm is fixed at the origin of a co-ordinate system as shown. The sphere is uniformly charged with a charge density ? = -312 ?C/m3. Concentric with the sphere is an uncharged spherical conducting shell of inner radius b = 10.1 cm, and outer radius c = 12.1 cm.
1) What is V(b), the electric potential at the inner surface of the conducting shell? Define the potential to be zero at infinity.
2) What is V(a), the electric potential at the outer surface of the insulating sphere? Define the potential to be zero at infinity.