Question

A spherical shell with a net charge of 3Q surrounds a point charge of -q at the center of the shell. The charges on the inner and outer surfaces of the shell are:

Answer 1

1) The charge on the outer shell is +4·Q

2) The charge on the inner shell is +Q

Step-by-step explanation:

1) The given parameters of the spherical shell are;

The net charge on the spherical shell = 3·Q

The point charge surrounded by the spherical shell = -Q

Let 'x' represent the charge on the outer shell, and let 'y', represent the charge on the inner shell, we have;

The net charge, 3·Q = -q + x

∴ x = 3·Q + Q = 4·Q

The charge on the outer shell, x = 4·Q

2) The net charge in the shell is zero, therefore, the charge on the inner shell, 'y', is given as follows;

-Q + y = 0

∴ y = +Q

The charge on the inner shell, y = +Q