# Gauss Law

1. Mar 1, 2004

### tandoorichicken

A point charge Q is at the center of a conducting spherical shell of radius R. The total charge of the shell is -Q. (a) What is the field in the region between the point charge and the shell? (b)What is the field outside the shell?

I think I got part (a): $$F = \frac{kq_1 q_2}{r^2} = \frac{kQ(-Q)}{R^2} = -\frac{kQ^2}{R^2}$$
$$E = \frac{F}{Q} = -\frac{kQ}{R^2}$$

Not quite sure how to do part (b) though.

2. Mar 1, 2004

$$\int_S \boldsymbol{E}\cdot d\boldsymbol{A} = \frac{Q}{\epsilon_0}$$