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Homework Help: Emf and current

  1. Feb 19, 2008 #1
    1. The problem statement, all variables and given/known data
    A magnetic field is perpendicular to the plane of a single-turn circular coil. The magnitude of the field is changing, so that an emf of 0.76 V and a current of 3.1 A are induced in the coil. The wire is the re-formed into a single-turn square coil, which is used in the same magnetic field (again perpendicular to the plane of the coil and with a magnitude changing at the same rate). What emf and current are induced in the square coil?

    2. Relevant equations


    3. The attempt at a solution
    i found the emf (.589V) but i can't figure out the current. what do i do?
  2. jcsd
  3. Feb 19, 2008 #2
    Well your equation is wrong, it's Ohm's Law, remember

    So if you know the voltage and current, you can find the resistance of the coil, which doesn't change. Therefore if you change the voltage(which you've done by reshaping the coil), you can find the current induced
  4. Feb 19, 2008 #3
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