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Can rotation wt, lift leverage wt

  1. Apr 27, 2008 #1
    Question: On one side of a wheel there is 50 lbs of weight, if the wheel is released the weights would rotate with the wheel until the weights where at the bottom and stop. Lets say this wheel has a shaft in the middle of the wheel that turns as the wheel does, if you put weights on one side of the wheel, when the wheel is released the the wheel and shaft turns until the weights stop at the bottom. Ok on the shaft there is bar welded to it, a long enough bar to use for leverage as the wheel turns {like a fan blade attached to its shaft}. Now lets say we have a balance scale or a teeter totter with 15 lbs at one end. If 50 lbs of weight in rotation on a wheel is pushing down with the attached bar, could the bar push down on the other end of the teeter totter that has no weight and lift the 15 lbs of weight on the other end of the teeter totter?
  2. jcsd
  3. Apr 27, 2008 #2


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    Staff Emeritus
    Science Advisor

    Certainly if the bar provides a moment sufficient to exceed the moment applied by the 15 lb weight. Basically shaft through the wheel and the bar behave likd a cam shaft.
  4. Apr 27, 2008 #3


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    Staff: Mentor

    I'm not completely sure I understand your scenario (a picture would help), but yes, you can use a lever to lift a 15 lb weight with a 50 lb weight.
  5. Apr 27, 2008 #4
    Ok lets say we have a ball weight or round weight of 10 pounds and roll it down a tube or half tube that is 5 ft long and at a 45% slope and at the end of the tube there is a stopping point. The end of the tube or the place where the ball stops is attached only by bearings that slide forward and after 2 inch's a metal lip will stop the forward motion of the small portion of the tube that slides. If there is 40 lbs of pressure an inch wide on top of the tube and the 10 lbs ball hits the end of the tube that can slide forward, {will it slide}.
  6. Apr 27, 2008 #5
    45 degree slope
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