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Why the direction of the current is determined by which way you move the magnet

  1. Jun 2, 2007 #1
    why the direction of the current is determined by which way you move the magnet through the coil?
  2. jcsd
  3. Jun 2, 2007 #2
    because there is a negative sign in faraday's law
  4. Jun 2, 2007 #3
    explain deeper please. Thank you.
  5. Jun 2, 2007 #4
  6. Jun 2, 2007 #5
  7. Jun 2, 2007 #6
    i almost started to use swear language.
  8. Jun 2, 2007 #7
    so what the fsck do you want?


    there are the graphs, showing the current vs time.
    and formulas are neccesary.
    what do you want to undertand, if you are not familiar with the basics?
  9. Jun 2, 2007 #8
    I am interested about the electrons. I don't need equations.
  10. Jun 2, 2007 #9
    In my imagination (without any formulas or graphs), thing can be like this. Electrons move and create magnetic field. The direction of the field is always perpendicular to the direction of the electron, and let say to the right. It is something like when you run, you hold a board which is 45 degrees off the running derection and facing to the right. then you always create wind to your right hand.
    When you have a moving magnetic field, the electron would move so that it creates a M. fiedl that is opposite to the applying magnetic field. And so its moving direction depends on the direction of the field.
  11. Jun 2, 2007 #10
    because the current has to oppose the change in flux
    because of conservation of energy and i quote from my intro physics book

    "Think what would happen if Lenz's law were turned the other way around, that is, if the induced current acted to aid the change that produced it. You would then need to push a stationary magnet only slightly to get it moving, and the action would be self perpetuating..."

    and mcstar's explanation is very good.
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