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I have a question about pulley

  1. Sep 11, 2012 #1

    I have a question about pulley.
    There is fixed pulley: http://en.wikipedia.org/wiki/File:Polea-simple-fija.jpg http://en.wikipedia.org/wiki/File:Polea-simple-fija.jpg where you need to use e.g. 100N to lift 100N.
    There is moveable pulley: http://en.wikipedia.org/wiki/File:Pulley1a.svg http://en.wikipedia.org/wiki/File:Pulley1a.svg where you need to use e.g. 50N to lift 100N.

    Question: How does "reversed moveable" pulley look like, i.e. the one where I need to use 200N to lift 100N? I need it for my home gym.

  2. jcsd
  3. Sep 11, 2012 #2


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    Re: pulley

    On the image for moving pulley, picture weight hanging from the free end of the rope instead of from the moving pulley. It will take 200N of downward force on the moving pulley to lift the 100N weight in that case.
  4. Sep 11, 2012 #3
    Google images for a block and tackle, or a mobile crane block. Once you see one rigged up your answer should be self evident.
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