Given:
Two uncharged conducting spheres, A and B, are suspended from insulating threads so that they touch each other.
A negatively charged rod is held near, but not touching sphere A.
Someone moves ball B away from A.
To find:
The types of charges on the spheres
Explanation:
The negatively charged rod induces a positive charge on the left side of sphere A and a negative charge on the right side of sphere B. The positive charge on the right side of sphere A induces a negative charge on the left side of sphere B and a positive charge on the right side of sphere B but the magnitude of the negative charge dominates so sphere B is negatively charged.
Hence, sphere A is positively charged and sphere B is negatively charged.
