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Homework Help: Calculate EMF Induced

  1. Jan 14, 2010 #1
    Can anyone point me in the right direction? I'm awful with electromagnetism.
     
    Last edited: Jan 14, 2010
  2. jcsd
  3. Jan 14, 2010 #2

    Matterwave

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    Do you know Faraday's law? This is a pretty straight forward application of Faraday's law. Just do the EMF induced in 1 turn of the wire, and then multiply by 100 since there's 100 turns. It's just that simple.
     
  4. Jan 14, 2010 #3
    It's finding the EMF induced in one turn that's the problem. I know EMF=-d[tex]\Phi[/tex]/dt but I don't know how to find that when I'm just given the rate of increase of B.
     
  5. Jan 14, 2010 #4

    Matterwave

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    [tex]\Phi=\int_S{BdA}[/tex]

    Now, since the B field is constant over that surface, and is perpendicular to that surface:

    [tex]\Phi=B*A[/tex]

    Therefore

    [tex]\frac{d\Phi}{dt}=\frac{d(B*A)}{dt}[/tex]

    Can you figure it out from there?
     
  6. Jan 14, 2010 #5
    Thanks for your help. Iurns out I was using the circumference rather than the area, which was giving me the wrong answer!
     
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