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Levitate a coin using two powerful magnets

  1. Jul 24, 2010 #1
    Hello Everyone,

    I was wondering if you could levitate a coin using two powerful magnets on wither side of the coin? I mean, if the magnets equally attract the coin(provided they are equally strong), there must be a point where the force of attraction from both the magnets is equal and if that point can be found, it must be possible that the coin just stays in air, being equally attracted by the magnets. Or is it that the magnets might cancel out each others forces, and that point might be a null point? Thanks! :)
  2. jcsd
  3. Jul 24, 2010 #2
    Re: Levitation.

    It's not stable with permanent magnets. You can use electromagnets with a feedback control system to hold it steady.

    It's not stable for the same reason you can't balance a marble on the edge of a knife. It will fall one way or the other.
  4. Jul 24, 2010 #3
    Re: Levitation.

    You can do something like this using electromagnets - its the basis of the Maglev system.
  5. Jul 24, 2010 #4


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    Science Advisor

    Re: Levitation.

    Also depends on the coin. I found that US coins are universally non-magnetic, but coins of some other countries are.

    Of course, you can still levitate any conducting object, in principle, but then you'd be using oscillating magnetic field, and you'll be repelling the object, rather than attracting it.
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