# Electric charge, simple problem for most of you.

1. Sep 1, 2013

### Fishingaxe

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

A) Two electric charges each with the charge of -35 nC is 0.70m apart from each other. With how big of a force do they impact each other?

B) A small metallic ball has a positive charge of 25nC. A particle with the charge +2.0nC is affected by a repellent force that's caused of the metallic ball. At what distance is the force of the ball 60 µN.

2. Relevant equations

3. The attempt at a solution

I'd really love some clues or perhaps links to equations that are relevant to these types of problems. I've a hard time imagining that these problems are hard once you know the relevant equations since this is the most basic physics there is.

2. Sep 1, 2013

3. Sep 1, 2013

4. Sep 1, 2013

### Fishingaxe

Thank you very much!

5. Sep 25, 2013

### Fishingaxe

Is this correct? F = q1*q2 / r^2 = -35*-35/0.49 = 2500?

And if so, what is the power measured in?