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Perpetum movil that will last as long as earth rotation

  1. May 15, 2005 #1
    Put a giantic gyroscope anywhere, in 24 hours it will have completed a revolution, cranck together the 24 hours rotation with the gyro rotation, if the gyro is heavy enough and the friction low enough it will spin as long as the earth spins
    Second option, put a giantic powerball at 45º latitude, once started the earth rotation will feed it
     
  2. jcsd
  3. May 15, 2005 #2

    If the friction has ANY value above zero, your Gyro will stop spinning well before the Earth does!
    (And it will have a friction value above zero!)
     
  4. May 15, 2005 #3
    well hello there aviator.
     
  5. May 15, 2005 #4

    Danger

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    I was just thinking the same thing...
     
  6. May 15, 2005 #5
    ... er, why? Have I missed something here?
     
  7. May 15, 2005 #6

    brewnog

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    He's back! Hurrah!
     
  8. May 15, 2005 #7

    Danger

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    I'm giving the benefit of the doubt for now, but just check back to posts by aviator and icarolo to see why the suspicion arises.
     
  9. May 15, 2005 #8
    Check the powerball you have to make a movement with it to accelerate it identical to that one that it would make in a 45º latitude by earths rotation.
    It would only need a initial momentum and earth would accelerate it.
    The powerball has friction but it reaches 15000 rpm by twisting it in your hand as earth would in a 45º latitude.
    Just think in slower motion, heavier powerball, bigger momentum
     
  10. May 15, 2005 #9

    krab

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    I don't know what a powerball is, but what is your point? That you can get energy from the earth's rotation? What's new about that? Earth's rotation (wrt the moon) causes tides, and hydroelectric generators can convert tides to electricity. Earth's rotation (wrt the sun) causes weather, and from this we already have hydroelectric river dams, windmill energy, etc. This seems like "free" energy, but tides and weather are gradually and continuously slowing the earth's rotation.
     
  11. May 15, 2005 #10
    You are right Krab this energy could be in long term even worse than fossil fuels because it would slow down the earth.
    But taking into account that precession is the vectorial product of the gyro torque together with the force of gravity we may conclude that force of gravity is transformed into an horizontal displacement, precession, of the gyro.
    Wouldnt it be an interesting experiment to build a gyro that crancked together the precession with the gyro spin to see if as the vectorial product says the force of gravity would be converted into an horizontal and usable force?
     
  12. May 15, 2005 #11

    russ_watters

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    I don't see the point of running an experiment - as Krab said, we already have tidal power plants that demonstrate the conversion of rotational energy to electrical via tidal forces. It doesn't work the way you describe, but it does work.

    Regarding slowing the earth's rotation - no. The tides are already slowing earth's rotation, by harnessing that we do not add a significant additional amount of friction.
     
  13. May 15, 2005 #12
    I don't think there's any doubt at all that it's aviator. It's like the hydra - you chop off one head (aviator) and two heads spring up (icarolo) and (capullosois).
     
  14. May 15, 2005 #13

    Danger

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    What throws me off a bit is that the spelling gets a little better each time. Maybe he's just taking more time to proof them, and bought a dictionary. He sure is a persistent little bugger.
     
  15. May 16, 2005 #14
    I have made an experiment to measure if a precessing gyro holds its torque as long as a not precessing gyro.The results were their lasting the same.
    To me this means that although precession is due to the gyro torque, the work that produces precession doesnt come from the gyro because if it was this way it would have lasted shorter precessing than no precessing.
    This work that produces precession may come from gravity.
    therefore if in a gyro you cranck together the spinning with the precession you may obtain a constant work from gravity.
    I dont think this have been tried experimentally before so if someone is investigating this is a new idea that might be worth trying.
     
  16. May 16, 2005 #15

    russ_watters

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    Sorry, but that's complete and utter nonsense. You didn't take any actual measurements or do any calculations, did you?
     
  17. May 16, 2005 #16

    BobG

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    You're right. The precession is due to gravity. Here's a link that should give you more info on how gravitational torque causes a spinning wheel to precess
     
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