Consider three identical metal spheres, A, B, and C. Sphere A carries a charge of +3q. Sphere B carries a charge of -q. Sphere C carries no net charge. Spheres A and B are touched together and then separated. Sphere C is then touched to sphere A and separated from it. Lastly, sphere C is touched to sphere B and separated from it.
(a) What is the ratio of the final charge on sphere C to q? What is the ratio of the final total charge on the three spheres to q
(b) before they are allowed to touch each other and
(c) after they have touched?