Question

A metal sphere A has charge Q. Two other spheres, B and C, are identical to A except they have zero net charge. A touches B, then the two spheres are separated. B touches C, with C grounded during this contact, then those spheres are separated. Finally, C touches A and those two spheres are separated. How much charge is on each sphere?

Answer 1

Answer:

A= Q/4 B=0 C=Q/4

Explanation:

The initial condition, is as follows:

A=Q B=0 C=0

When A is brought to contact with B, as both spheres are conductors, charge distribute evenly between the two spheres, so after this, the charges on the spheres are as follows:

A= Q/2 B=Q/2 C=0

If B touches C, while C is grounded, this supplies a infinite source of sink of charge, so both spheres lose any charge.

At this stage, the charge distribution is as follows:

A = Q/2 B=0 C=0

Assuming C is not grounded, when finally touches A, the charge on A distributes evenly between A and C, so the final situation is as follows:

A = Q/4 B=0 C=Q/4