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Mechanical leverage to increase length?

  1. Jul 8, 2014 #1

    Im trying to increase the length of a movement of a rope so when one rope is pulled the other rope movement is increased x 2 (it is attached across). So far i have tried gears whice has somewhat worked but it increases the force as well. Is there any other way to achieve this amplification with the same force?
  2. jcsd
  3. Jul 8, 2014 #2


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    Staff: Mentor

    Sorry, no, that would violate conservation of energy.
  4. Jul 8, 2014 #3


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    Science Advisor

    The energy expended will be proportional to the distance moved, multiplied by the force applied.
    Conservation of energy requires that the force * distance product remain equal for the input and output.
    Twice the force over half the distance is a possible solution using a mechanical system.
  5. Jul 9, 2014 #4
    Thanks for the replies...i thought there'd be np solutions. Is there any other way except gears, levers? With minimal friction, energy loss?
  6. Jul 9, 2014 #5


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    Science Advisor

    A bicycle chain over a movable sprocket, or an endless chain, differential pulley.

    Fluid coupled hydraulic cylinders, with different cross section cylinders to set the ratio.
  7. Jul 9, 2014 #6
    Thanks for the ideas, ive tried all of them
    but theres too much friction and energy loss im creating.
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