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Multiple current loops

  1. Jan 14, 2010 #1
    I assume that if one has several current loops that the magnetic fields that they generate just add together linearlly. Just want to make sure.
     
  2. jcsd
  3. Jan 14, 2010 #2
    Yup...that is how it looks to be (at least classically).
     
  4. Jan 14, 2010 #3

    Matterwave

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    to first order they do, but I think the interaction between the current loops and other magnetic fields would induce emfs which would change the magnetic fields produced, and would further induce emfs, etc.

    I suppose, if you assumed no coupling, the fields would just add linearly.
     
  5. Jan 14, 2010 #4
    Interesting. How would you solve this problem with coupling? The law of Biot and Savart would not work. I guess you would hold the currents in the loops constant.
     
    Last edited: Jan 14, 2010
  6. Jan 14, 2010 #5

    Matterwave

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    For example, for 2 loops:

    [tex]emf_1=\epsilon_1-\frac{d\Phi_{21}}{dt}[/tex]

    [tex]emf_2=\epsilon_2-\frac{d\Phi_{12}}{dt}[/tex]

    Where [tex]\Phi_{12}[/tex] that's the flux on 2 due to 1 and vice versa. It's a coupled differential equation. If you had 3 loops, you'd just have more terms and more equations. Don't quote me on this, it's been a while since I've done this stuff :P.
     
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