# Gauss's law and electric flux

1. Jan 21, 2008

### jincy34

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

What is the net electric flux through the the torus if a=-6 nC and b=60 nC ?

2. Relevant equations

Electric flux=Qin/E

3. The attempt at a solution

I solved with Qin being 6*10^-9 C as it is the charge inside and E0=8.85*10^-12. I got 678 for electric flux. But it is wrong.

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Last edited: Jan 21, 2008
2. Jan 21, 2008

### G01

$$\epsilon_0 = 8.85*10^{-12}$$ not $$8.85*10^{-9}$$.

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3. Jan 21, 2008

### jincy34

I put the right value for E0. But, I am not sure if the charge I am using is right or not. Is the charge inside 60nC, 6nC or net charge?

Last edited: Jan 21, 2008
4. Jan 21, 2008

### G01

Is the +60nC charge contained inside the surface of the solenoid?