If a charged conductor is inserted into a hollow conductor then it is touched the
inside wall so the charge from the first conductor will move to the second conductor, no matter if the second conductor has been charged previously. If there is no difficulty due to the isolation process, the charge on the hollow conductor can be added by repeating this process. With the increasing potential conductor, the greater the repulsive force that works against them each time the charge is added to it so that one time the conductor cannot accommodate more charge.