Posted by Scott on .
A point charge of 1.8 uC is at the center of a Gaussian cube 55 cm on edge. What is the net electric flux through the surface?
I have no idea where to start with this problem.

College Physics 
drwls,
According to Gauss' Law, you will get the same answer no matter where the charge q is placed inside the box, and no matter how large the box is. It does not even have to be a cube, as long as it encloses the charge.
Total flux = q/(epsilonzero)
= 1.8*10^6/8.82*10^12
= 2.04*10^5 (N*m^2/C)
That is a lot easier than doing the actual integhtration of E(normal) over the six sides of the cube, but the answer will be the same.