Rotate pulleys using gravity.

Discussion in 'Propulsion' started by Jigar111, Nov 21, 2006.

  1. marshmat
    Joined: Apr 2005
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    marshmat Senior Member

    It is indeed good to exercise one's understanding of physics.
    For instance, the whatever-it-is in post 1. If it is symmetrical, it doesn't do jack. If it's not symmetrical, the top part falls down. The steady state solution in both cases is that it sits there and does nothing. The only difference is that in the second case, there is a transient term in the solution which disappears once the device comes to rest. No more energy can come out of it, than the difference in potential energy between the state it's drawn in and the state where it is done collapsing under its own weight. Which is pretty small; if the thing's a half-metre high overall and the upper part weighs 10 kg, you're talking maybe 50 joules, tops. Bottom line, if you believe that it's good for anything, go dig out your grade 10 physics book because I assure you, it's pretty darn useless.
  2. SmithCraft64
    Joined: Aug 2006
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    SmithCraft64 Junior Member

    I see your point as a whole - = = summation.
  3. stevel
    Joined: Aug 2004
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    stevel Lost at sea

    I got one right!

    Thanks Matt! That's how I understood it to be.

  4. RHough
    Joined: Nov 2005
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    RHough Retro Dude

    Is this a system for moving canting keels? :p
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