Question

Three identical metal spheres each carries different of +3.0uc, -2.0 and -7.0uc. these object are brought simultaneously in contact, so that each touches the others. Than they are sperated . After separation one spheres is brought in contact with fourth neutral identical sphere what is the final charge on each of the four spheres

Answer 1

When the three identical spheres are brought in contact with each other, the charges will distribute evenly among them since they are all identical. So each sphere will have a charge of (+3.0uc - 2.0uc - 7.0uc)/3 = -2.0uc.

After separation, one of the spheres with a charge of -2.0uc is brought in contact with a fourth neutral identical sphere. When they are brought in contact, the charges will distribute evenly among them. So the final charge on each of the four spheres will be (-2.0uc - 0uc)/2 = -1.0uc.

Therefore, the final charge on each of the four spheres will be -1.0uc.