# Homework Help: Kinetic Energy Gain due to Coulomb Force

1. Sep 4, 2014

### quantumfoam

1. The problem statement, all variables and given/known data
Hi guys! I have a problem pertaining to the kinetic energy gained by a point charge from interacting with a another point charge. Here's the problem: A point charge of mass m1 and charge q is placed near another point charge with mass m2 and charge Q. Both charges are of equal sign. The two charges are separated by a distance R. If the charge q was held stationary and the charge Q was allowed to move, what would be the resultant velocity of charge Q given that it has no initial velocity?

2. Relevant equations
ΔV=kQq/R and ΔKE=(m2/2)(v2)

3. The attempt at a solution
I equated the change in kinetic energy of Q that would result from the electric repulsion with the change in electric potential energy between the two charges. I then rearranged the equality to solve for v:

v=(2kQq/Rm2)1/2

Is this a correct method of solving this problem?

2. Sep 4, 2014

### Satvik Pandey

I think your solution is right.