# Homework Help: Uniformly charged spheres

1. Jan 15, 2009

### simple_kuri

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

Suppose that the magnitude of the charge on the yellow sphere is determined to be 2q. Calculate the charge q_red on the red sphere.
Express your answer in terms of q , d_1 , d_2 , theta and .

Hi Guys iv done the first two bits to this problem
the sign of the charge on the yellow sphere is negative and the sign of the charge on the red sphere is positive.

I cant do this third part though.
It would be gr8 if you could help me out.

I dont know where to start.

2. Jan 16, 2009

### CompuChip

Did you forget to tell us anything? Like the charge of the blue sphere (I would expect it to be q, but you didn't say that). Also, the charge on the red sphere could be anything. You need some more information to determine it, like the red sphere is stationary or is at a minimum of the electric potential.

Please state the entire problem.

3. Jan 18, 2009

### simple_kuri

Thank u for the reply.
I was actually missing out that information which is why i got stuck on it.
I should have checked the notes they had given with the question.