# Finding the flux of an electrix field

1. Apr 15, 2012

### spaghetti3451

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

A charge q sits in the back corner of a cube, as shown in the attachment. What is the flux of E through the shaded side?

2. Relevant equations

3. The attempt at a solution

I know that I need the surface integral of E over the shaded area, but the problem is with choosing the proper coordinates and the origin.

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2. Apr 15, 2012

### Daniiel

Gauss's law finds the charge ENCLOSED,

So one way to do this question is to enclose the charge by surrounding the charge by another 7 boxes.

Then you can compute the integral as the charge is now enclosed.

There will be 24 faces after surrounding the charge, so integral will produce a flux 24 times the flux through one face (seeing as you only need the flux through one face) and I think you can take it from there,

I've seen this question in griffiths electrodynamics before I think