# Spherical Shell

## Homework Statement

I have a simple question.

There is positive point charge in the center of a sphere 2.5 micro c. The spherical shell has inner radius of 60 cm and outer radius of 90 cm. The net charge of the spherical shell is equal to zero.

## The Attempt at a Solution

Now the net charge = 0 :

Does this mean the 2.5 + charge on the inner radius + charge on the outer radius = 0?
Because that's what I did while solving the problem.

which gave me Charge on inner radius = -2.5 and charge on outer radius = 0

But the solution manual says that charge on the inner radius + charge on the outer radius = 0

which means Charge on inner radius = -2.5 and charge on outer radius = +2.5