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Homework Help: Separation distance between wires - Magnetic fields

  1. Jun 24, 2011 #1
    1. The problem statement, all variables and given/known data
    http://i.imgur.com/mgIkS.png
    Two long parallel wires carry currents of 2.03 A and 8.83 A. The magnitude of the force per unit length acting on each wire is 4.49*10^5 N/m. Find the separation distance of the wires expressed in millimeters.


    2. Relevant equations
    I'm not entirely sure.


    3. The attempt at a solution
    I thought that I would need to use the formula:
    http://latex.codecogs.com/gif.latex?F_{21}=(\mu_0*I_1*I_2*L )/(2\pi d)
    I don't have L however, so how do I solve for d?
     
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Jun 24, 2011 #2
    Actually you have the right formula, just understand the parameters involved and relate to the given problem.

    Hint: "The magnitude of the force per unit length acting on each wire is 4.49*10^5 N/m."
     
  4. Jun 24, 2011 #3
    So are you suggesting that L=1?
    Edit: I tried it with L=1 and it worked. Thanks!
     
    Last edited: Jun 24, 2011
  5. Jun 24, 2011 #4
    We'll you can say that, but I can also say L=2 and my F = 2.245x105 N/m.

    What I want you to understand is that you don't need to know L as you are readily given with F/L.
     
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