Two uncharged conducting spheres, A and B, are suspended from insulating threads so that they touch each other. While a positively charged rod is near A (not touching sphere A), the spheres are moved apart. How will the spheres be charged, if at all?
Solution. Posted on Tuesday, May 5, 2015.
The charged rod attracts the electrons in the conductor. There is an excess of electrons at the surface of the sphere A, and deficiency of electrons at the surface of the sphere B. When we separate the two spheres, the sphere A is left with a net negative charge, and the sphere B is left with a net positive charge. This process is referred to as charging by induction.