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Homework Help: What is the magnitude of the induced current in the coil

  1. Apr 14, 2007 #1
    The component of the external magnetic field along the central axis of a 50−turn coil of radius 5.0 cm increases from 0 to 1.0 T in 4.3 s. (a) If the resistance of the coil is 2.9 Ω, what is the magnitude of the induced current in the coil? (b) What is the direction of the current if the axial component of the field points away from the viewer?

    I am trouble starting this problem.
    Which equation am I suppose to start with.
    I am trying to use
    emf = vBL
    but I don't know what v would be.
    i tried to use Faraday's law equation but i didn't have all of the exponents.
  2. jcsd
  3. Apr 15, 2007 #2


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    Homework Helper

    You are not applying Faraday's law correctly for this particular question. For (a), you want to consider the rate of change of magnetic flux through the coil. Think of the coil as 50 circular loops. Think of the area of a loop.
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