A charge Q is placed at height b abouve a plane horizontal conducting slab.
Write down the electric field, E(r), at a general point r above the slab (taking the point r=0 to be the point on the slab directly beneath the charge), and show that it satisfies the appropriate boundary conditions.
The Attempt at a Solution
Ok, I know that the electric field above a plane is sigma*r/2*epsilon_zero*r, but since this slab has a thickness where there will be no electric field, does this make a difference? Can I still use Gauss' Theorem? And what does it mean by "appropriate boundary conditions"? Just that it's continuous at the surface of the slab and zero at infinity?
Just, generally, where do I start with this question?