Charging by Induction
A charged object may induce a charge in a nearby neutral object without touching it. For example, if a positively charged object is brought near a neutral object, the electrons in the neutral object are attracted to the positive object. Some of these electrons flow to the side of the neutral object that is nearest to the positive object. This side of the neutral object accumulates electrons and becomes negatively charged. Because electrons leave the far side of the neutral object while its protons remain stationary, that side becomes positively charged. Since the negatively charged side of the neutral object is closest to the positive object, the attraction between this side and the positive object is greater than the repulsion between the positively charged side and the positive object. The net effect is an attraction between the objects. Similarly, when a negatively charged object is brought near a neutral object, the negative object induces a positive charge on the near side of ...