Question

A conducting sphere carrying charge +5 C is surrounded by a spherical conducting shell. If charge 2 C is moved to a position between the shell and the sphere, what is the magnitude of the net charge on the inner surface of the shell?

Answer 1

As the conductor resides the all charges on the outer surface so the charge on outer surface of the conducting sphere is +Q. Since total charge inside a conducting shell is zero so the inner surface of the shell will get charge -Q and outer surface will get positive charge +Q. When charge , q is placed in between the shell and the sphere, the charge on inner surface becomes (-Q-q) and the charge on outer surface becomes (Q+q).