Determine the net charge contained within the cube

22steve

1. Homework Statement
At each point on the surface of the cube shown in the figure, the electric field is parallel to the z axis. The length of each edge of the cube is 3.7 m. On the top face of the cube = -40 N/C, and on the bottom face of the cube = +10 N/C. Determine the net charge contained within the cube.

2. Homework Equations

flux = E x A

flux = charge enclosed/ permittivity constant (epsilon-naught)

3. The Attempt at a Solution

I first plugged the numbers to find the flux of the the ends of the cube, then the plugged that into the second equation to find the charge enclose, but I got a really small number that wasn't right.

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rootX

What number you got?

22steve

-6x10^13 I meant a really big number.

rootX

I am getting ..6. ..E-9.

Flux is 684.5 (simply adding two together)
and then electric constant is 8.854E-12

22steve

Ahh, and then its negative, I didn't add the two together I was only using one. Dumb mistake, but thank you soo much!

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