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Proof of induction

  1. Apr 7, 2008 #1
    In my physicsbook they show that the induced voltage in a metal rod is e=lvB, and after that show that that can be written as [tex]e=-\frac{d\phi}{dt}[/tex]

    But how do you prove that this actually apply to any rod or circuit, not just to a metal rod moving through a uniform B-field?
  2. jcsd
  3. Apr 7, 2008 #2


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    I think the short answer is : Maxwell's equations, more specifically the one particular Maxwell equation known as Faraday's Law of Induction

    [tex] \nabla \times \vec{E} = -\frac{\partial \vec{B}}{\partial t} [/tex]
  4. Apr 7, 2008 #3
    Try drawing your ciruit out as a rod sliding on two railings, which are connected at one end. Then the area to be used in your flux is the area enclosed by this new circuit.
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