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Different poles and arrange them in a circle

  1. Apr 7, 2004 #1
    say I take magnets of different poles and arrange them in a circle sorting them by one + and then another - and so on and I fixed them so they would nto move. What would happen if you placed a metal inthemiddle. Would this be kinda like a perpetual motion machine since the magnets onthe outside would be pulling/pushing on the middle metal creating kinetic energy? just something ithought of on the bus.
  2. jcsd
  3. Apr 7, 2004 #2


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    If you placed it exactly in the middle, it would just stay there, since there would be just as much force on either side.

    If you mean "machine" in the sense of an object from which work can be extracted, then it will be in perpetual motion as long as you supply it with some source of energy. You can know this without ever looking at the specifics of your configuration since you are talking about magnets, which is based on a classical model of electromagentism, which in tern takes energy conservation of a closed system as a fundamental premise.

    Kinetic energy cannot be "created" in the ex nihilo since; it must be converted from another existing form.
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