(a) The electric field at r = 0.115m from the center is measured to be E = -3.10
10
3N/C(E is negative, since it is pointed inward).
, where q is the charge of the insulating sphere.
(b) The electric field at R = 0.500m from the center is measured to be E' = 2.50
10
2N/C(E' is positive, since it is pointed outward).
, where Q is the net charge of the insulating sphere plus the conductig sphere.
∴The net charge on the hollow conducting sphere is Q - q = 1.15 x 10-8C.
(c) A charge of +q forms on the inner surface to guard the interior of the conductor. So the total charge on the inner surfaces of the hollow conducting sphere is +q = 4.56 x 10-9C. A charge of +Q = 6.95 x 10-9C forms on the outer surface of the conductor.