# Point charge and a plane question

1. Jan 26, 2008

### joker_900

OK I'm really not understanding any of this, please help, and any tips on how to go about problems like this in general would be much appreciated.

1. The problem statement, all variables and given/known data
A point charge Q is situated a distance d from an infinite conducting plate connected to ground. Show that the total charge on the conductor is -Q.

2. Relevant equations
I'm not sure but I think the Gauss equations?

3. The attempt at a solution
I've found the electric field at any point on the plane to be

[kQ/(x^2 + y^2 + d^2)^(3/2)] (-x, -y, d)

But like I said, I don't really know what I'm doing!

2. Jan 26, 2008

### Mindscrape

Do you know the method of images? I suppose that regardless of whether or not you know, you ought to learn it to do the problem. This is a really standard image problem, and I think that once you look it up that you will not have any problems.

Edit:
I don't know how far you plan on going in physics, if for example you will do EM with vector calculus, but Griffiths definitely has the best EM book out there, and now that I look this exact problem is an example he goes over.

Last edited: Jan 26, 2008