Question

A longer conducting cylinder carrying a charge $+q$ is surrounded by a conducting cylindrical shell having charge $-2q$. The charge on the inner and outer side of conducting shell is :

• A. $q,-q$
• B. $-q,-3q$
• C. $-q,+3q$
• D. $-q,-q$

Answer 1

The correct option is D $-q,-q$

Firstly, it is given that there is charge $q$ outside the conducting shell so for balancing this there will be $-q$ charge outside the conducting shell
now we know that total charge on shell is $-2q$
so charge inside the shell =$-2q-(-q)=-q$