Two isolated conducting spheres (S1 of radius 0.030 m and initial charge + 6.0 nC and S2 of radius 0.040 m and initial charge + 2.0 nC) are connected by a conducting wire. Charge will flow in the wire until:
(A) both spheres are equally charged.
(B) the net charge is zero.
(C) the force of repulsion between the two spheres becomes equal.
(D) both spheres have the same surface charge density.
(E) both spheres are at the same potential.
