Charge Q is uniformly distributed over a body. How should the body be divided into two parts, so that force acting between the two parts of body is maximum for a separation between them ?

Explanation

Charge Q is uniformly distributed over the body. Now, suppose the body is broken into two parts such that the charge on one part of body is q and on the other is Q - q. The force existing between the two parts separated by distance r will be,
`F =k(q(Q-q))/r^(2)`
Now, for the maximum force E.
`q(Q-q) = Qq-q^(2)` should be maximum.
`therefore q = Q/2`