# Homework Help: Easy problem , not for me though

1. Jun 30, 2009

### Luhter

If I have a sphere and that has radius r and electric charge density of x
Then outside the sphere , in void (permittivity=$$\epsilon 0$$) , a point A which is at r+a distance from the sphere's center . What is the charge at point A ?

Ok i tried this at exam in a way with Gauss law,but it seems it was no good ... so I'm curious how is made

2. Jun 30, 2009

### djeitnstine

Gauss's Law works, how did you attempt it? $$\int E \cdot dA = \frac{Q_{enc}}{\epsilon_0}$$

what type of charge density is it? linear, area or volumetric... either case you need to convert the enclosed charge term to its density form.

3. Jul 1, 2009

### turin

This question is nonsensical (or trivial if all of the charge is described by the problem statement).

4. Jul 1, 2009

### Wax

I'm curious, which physics is this?

5. Jul 1, 2009

### queenofbabes

I suppose the question is actually asking for electric field strength?