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Homework Help: Electromagnetic Induction and Faraday's Law

  1. Feb 26, 2005 #1
    The generator of a car idling at 950 rpm produces 12.4 V. What will the output be at a rotation speed of 2500 rpm assuming nothing else changes?

    I'm guessing that is easier and I'm looking to make it harder. I can't find anything in my textbook involving rpm. I'm thinkin to use this formula
    E = NBAw but I'm actually not quit sure how to approach the problem.

    is N my rpm? and then I do an initial rpm and final rpm sequence?
  2. jcsd
  3. Feb 26, 2005 #2
    N is number of loop... [tex] \omega [/tex] is the angular velocity.....

    the rpm (rotation per minute, or radian per minute) is directly proportional to the angular velocity.... does that make sense to you?
  4. Feb 26, 2005 #3

    so i could set this up as a proportion?

    950/12.4 V =2500/x Volts ?

  5. Feb 26, 2005 #4
    I think you should also consider the back EMF.
  6. Feb 26, 2005 #5
    sorry, I'm not following. If all things remain constant why would I consider that? The back emf oppose the motion (Lenz's law) correct, but if everything remains constant... :confused:
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