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Homework Help: Why is the induced EMF inversely proportional to time (Faraday's law of induction)

  1. Mar 20, 2012 #1
    Hi, I am doing coursework on Faraday's law of induction. My assignment was to carry out experiments which confirm Faraday's law and also to explain the physics of how faraday's law works... My experiments all worked perfectly, producing straight line graphs showing that:
    [itex]\epsilon\propto[/itex] N
    [itex]\epsilon\propto[/itex] B

    I did not do any experiments to test [itex]\epsilon\propto[/itex]A ...

    I have explained the physics behind the first two results, but for the life of me I can't justify WHY the EMF is inversely proportional to time... I have thought about F = BIl = [itex]\frac{BQl}{t}[/itex], therefore the force on the delocalised electrons is inversely proportional to time... But it's all dead ends after that...

    Any help would be GREATLY appreciated!!

    Thank you in advance!!
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Mar 20, 2012 #2


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    Re: Why is the induced EMF inversely proportional to time (Faraday's law of induction

    Well if your EMF didn't vary with time, it would mean that your magnetic field would remain constant. Without it changing you cannot get an induced emf (well something has to change with time essentially).
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