Two point charges with electric potential energy?

AI Thread Summary
The discussion revolves around solving for two point charges that are 2.0 cm apart with a given electric potential energy of -180 microJoules and a total charge of 31 nC. The user understands the relevant equations but struggles to isolate the individual charges from the total charge and potential energy. They consider the possibility of dividing the potential energy to find equal charges but realize this approach may not be correct. The conversation highlights the need for a clearer method to break down the equations to find the individual charges. The user seeks guidance on how to proceed with the calculations effectively.
Netsurfer733
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Homework Statement



"Two point charges 2.0cm apart have an electric potential energy -180 microJoules. The total charge is 31 nC. What are the two charges?"

Homework Equations



V= k * q / r

The Attempt at a Solution



I understand that V = -180 * 10^-6, k = 9*10^9, r = 0.02m, and the TOTAL q=31*10^-9 C...but what does that leave us to solve, in this equation? I know we need to find the total charge of the both of them individually, but I don't know how to break this equation up to do that. Can anyone help me see this through?
 
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Hi netsurfer.
Let q_{1} and q_{2} be the charges you are asked to find.
How do these charges enter in your equation ?
 
Exactly, lol...I mean, I would think maybe if you cut the potential in half then solve for q then q1 and q2 would be equal? But that doesn't seem right at all... I'm a bit confused. How would I go about doing it?
 

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