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Faraday Cages and Induction

  1. Sep 27, 2010 #1
    Hey there, I was wondering whether the following scenario is possible:

    Say I have a Faraday Cage which contains electricity on the inside, could I use a magnet on the outside to create electricity on a conductor on the inside?

    If no, are there possible variations to this scenario which would allow you to get electricity to an object on the inside without physical contact to the outside?

    Thanks for your help!
  2. jcsd
  3. Sep 27, 2010 #2


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    Electricity could only be induced by a changing magnetic flux through a suitable wire structure inside the cage. However, a true Faraday cage, while it will not prevent static magnetic fields from penetrating, it will prevent the penetration of all electromagnetic waves. Any changing magnetic field is associated with an electromagnetic wave and thus the changing flux cannot penetrate the cage. You could physically change the flux by moving the coil or changing its area though.
  4. Sep 28, 2010 #3
    If you had a high enough frequency EM wave it could penetrate the metal shell. But then you would have to have a material inside that would absorb the radiation and not let is pass through like it did the metal shell .
  5. Sep 28, 2010 #4
    Great, thanks for your help guys!
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