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Perpetual Current Machine

  1. May 28, 2013 #1
    If a magnet could somehow oscillate in and out of a coil of wire and used to power a light bulb, could that power the light bulb forever?

    I learned in class that running through a magnet through a coil of wire could produce an electric current. If we had two magnets powerful enough to repel the magnet from side to side, could that create a perpetual electric current?

    Sorry if my question is stupid.

  2. jcsd
  3. May 28, 2013 #2


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    Staff: Mentor

    Its ok.

    It takes physical force to create that current, so the act of creating the current would slow the oscillation of the magnet.
  4. May 29, 2013 #3
    russ_watters is right. The magnet will be repelled to and fro between the two larger magnets, sure.. But the oscillations will slowly die and and the magnet will eventually come to rest in a position where the two repelling forces are equal. Ofcourse, there is the inductance of the coil involved too which might support or go against the motion of the magnet. But the essentials remain the same. The magnet will stop.
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