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How would you make this?

  1. Jan 30, 2008 #1
    the grey area is stationary and the outer circle should spin.. the black and red dots are magnets


    is there a diagram anywhere online or something? i tried searching and i couldn't really find anything except 6th grade science projects :p
    and before anyone asks... noooo this isn't homework lol
  2. jcsd
  3. Jan 30, 2008 #2
    Is this a type of motor? If so, you would need some way of varying the angles between the magnets and a means of putting energy into the motor.
  4. Jan 30, 2008 #3
    i guess it could be a motor :p

    so it IS possible? if the magnets were aligned exactly, would it need any energy to keep it spinning, or would the + - pull/push on the magnets keep it going?
  5. Jan 30, 2008 #4
    No, it would not. It would quickly move into the position shown and then stay there, putting up a fair amount of resistance to any movement. So, you would have to put in some energy just to make it spin and it would not do any useful work for you.

    The energy in magnets is generally unavailable; you can sort of think of it as being similar to the earth's gravitational potential energy which is only available by being placed in a certain position. Once that position doesn't exist, you have to do work to put it back.
  6. Jan 30, 2008 #5


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    Gold Member

    This looks suspicously like a design for a perpetual motion device.

    If you're in this for entertainment, great. But don't put valuable time into it.

    (And don't expexct this thread to stay open long.)
  7. Jan 30, 2008 #6
    so no one knows of a diagram or something i could look at to help me build this??

    and its not perpetual motion, though that would be cool :p
  8. Jan 31, 2008 #7


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    Science Advisor

    Sure. Look at any permanent magnet motor. TVP45's post is very helpful if you read it completely.
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