Microscopic views of objects are shown. In part a, a positive rod with positive signs is close to an insulator. The negative ends of all the molecules of the insulator are aligned toward the rod and positive ends of all molecules shown as spheres are away from the rod. In part b, a negative rod with negative signs is close to an insulator. The positive ends of all the molecules of the insulator are aligned toward the rod and negative ends of all molecules shown as spheres are away from the rod. In part c, a rod with negative signs is close to an insulator. Only the net charges are shown in the insulator. The insulator surface closer to the rod has positive signs. The other surface has negative signs.