Chapter 19, Problem 79GP

CE Four lightweight, plastic spheres, labeled A, B, C, and D, are suspended from threads in various combinations, as illustrated in Figure 19-47. It is given that the net charge on sphere D is +Q, and that the other spheres have net charges of +Q, −Q or 0. From the results of the four experiments shown in Figure 19-47, and the fact that the spheres have equal masses, determine the net charge of (a) sphere A, (b) sphere B, and (c) sphere C.