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Back emf and self induction

  1. Jan 16, 2014 #1
    In the case of self induction, when the intensity increases gradually an emf is induced which generates a back current " equal in magnitude, opposite in direction " to oppose the increase, so if that is right shouldn't the intensity in the coil Become ZERO till the intensity becomes steady???
  2. jcsd
  3. Jan 18, 2014 #2
    Well, there are two things going on here. There is the instantaneous current and then there is the rate of change of current. You have to think again at which one provides the magnetic flux and which one provides the change in flux.
  4. Jan 18, 2014 #3


    Staff: Mentor

    Where did you get the bolded part (equal in magnitude)? It is not correct.
    Last edited: Jan 18, 2014
  5. Jan 18, 2014 #4

    So it doesn't have to be equal ?
  6. Jan 18, 2014 #5


    Staff: Mentor

    I cannot think of any example where it is equal.
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