# A coulombs law problem

1. Jan 29, 2009

### corey7

1. The problem statement, all variables and given/known data
What is the magnitude of the force a +15 µC charge exerts on a +2.6 mC charge 41 cm away?

2. Relevant equations
F=Ke(Q1*Q2)/d^2

3. The attempt at a solution
Well I plugged in the numbers for the variables. Converted 15 and 2.6 to coulombs and 41 to meters. I did the math and got like .2088. I have to input my answer on this site and I have five tries to do so. I used three already so I really don't want to screw up again without help...or something like that...you get what I'm saying.

2. Jan 29, 2009

### LowlyPion

Welcome to PF.

I think your orders of magnitude are off. Check your powers of 10.

3. Jan 29, 2009

### corey7

Well you uhh may be right, and thanks for the welcome. I tried it again and I got 2.088 but I put that in and still got it wrong. Me == confused now. Maybe it wants an exact answer or its screwing me over for sig figs or something....maybe I'm just wrong.

4. Jan 29, 2009

### corey7

Ooof I read it over...hehe...yeah I converted 2.6 as if it were micro