# Gauss's Law problem

1. Jan 12, 2008

### samblue

1. The problem statement, all variables and given/known data

Ok so I', having some problems with Gauss's law. I know what it is, but I still cant get the answers right.

A metallic sphere of diameter 2*10-2m has been given a charge of 2 nC. State Gauss's law. Use this to determine the electrical field at the surface of the sphere. What is the electrical field inside the field?

2. Relevant equations

integral (E.dA)=Qenclosed/permitivity of free space

3. The attempt at a solution

the fist part is the equation written below.

However im not sure about the next part. How do I distinguish between the charge inside the spehere and the charge on the surface?

Thanks

2. Jan 12, 2008

### Staff: Mentor

Assuming electrostatic equilibrium, what's the charge inside a conductor?

3. Jan 12, 2008

### samblue

Not really sure. Is it zero? Becasue all of the charge passes through it?

4. Jan 12, 2008

### Staff: Mentor

Key fact (where electrostatic equilibrium holds): The electric field is zero everwhere inside a conductor. All the (net) charge on a conductor lies on its surface.

5. Jan 12, 2008

thanks