Two point charges with electric potential energy?

  • #1

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?
 

Answers and Replies

  • #2
75
0
Hi netsurfer.
Let [tex]q_{1}[/tex] and [tex]q_{2}[/tex] be the charges you are asked to find.
How do these charges enter in your equation ?
 
  • #3
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?
 

Related Threads on Two point charges with electric potential energy?

Replies
1
Views
16K
Replies
3
Views
2K
Replies
2
Views
3K
Replies
2
Views
681
Replies
9
Views
5K
Replies
0
Views
4K
Replies
2
Views
3K
Replies
1
Views
8K
Replies
1
Views
11K
Replies
8
Views
8K
Top