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Harnessing energy of a rotating mass

  1. Jun 2, 2008 #1
    Is it possible to harness some of the kinetic energy of a rotating mass to convert it to electricity? More to the point... If I wanted to put a light on a bicycle wheel, is there any way to power the light using the uniform accelerated circular motion of the wheel? Or are the gains of centrifugal "force" countered by the centripetal?

    It seems that generating energy mechanically like this would require relative motion of some sort... unless I could use the motion to turn a small propeller to turn a generator, etc...

    Last edited: Jun 2, 2008
  2. jcsd
  3. Jun 2, 2008 #2
    I don't think theres anyway to harness that power in the way you're thinking. You could put magnets on the wheel that would generate a current in a coil stationary to the wheel - you could do this near the axle or the top of the wheel.
    Can't think of anything other way.
  4. Jun 2, 2008 #3


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    They have existed for quite some time, they're called bicycle dynamos or bicycle generators.

    http://www.aztlanbicycle.com/images/products/lowrider-lights-mirror/LIGHT_GENERATOR_LIGHT_VISOR_34339.jpg [Broken]

    http://www.freepatentsonline.com/6703716-0-large.jpg [Broken]

    Last edited by a moderator: May 3, 2017
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