# Calculating the force between two electrons in a wire

Tags:
1. Feb 2, 2017

### helixkirby

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

An infinite line charge (wire) has lambda = lambda0. It produces an electric field of magnitude 5E4 N/C at a distance of 2m. Determine the typical force between two adjacent extra electrons in the wire

2. Relevant equations
E_line = lambda/(2pi*r*epsilon0)

3. The attempt at a solution
I managed to find lambda0 using the above equation, but now I'm stuck trying to find the force between the two electrons, how do I find thelectricity e spacing between them given the linear charge density, can anyone help me?

2. Feb 2, 2017

### Staff: Mentor

What are the units of λ?

3. Feb 2, 2017

C/m

4. Feb 2, 2017

### Staff: Mentor

Right. So how many electron charges make up a Coulomb?

5. Feb 2, 2017

### helixkirby

1/1.6E-19 = 6.25E18 electrons

6. Feb 2, 2017

### Staff: Mentor

So how many electrons per meter for your value of λ?

7. Feb 2, 2017

### helixkirby

epsilon0 * 5E4 *4pi*6.25E18 electrons per meter I believe

8. Feb 2, 2017

### Staff: Mentor

Okay. What's the result of the calculation? What does it tell you about the meters per electron?

9. Feb 2, 2017

### helixkirby

I finally got it, I inverted the calculation to get the meters per electron which was about 2.9E-14 m per electron, then used this with coulomb's law to get .28N, thank you so much, my professor was giving me cryptic hints when I emailed him.