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Heavier Weight Lifted By Lighter

  1. May 23, 2007 #1
    I was asked to contruct something to have a heavier weight lifted by a lighter weight, and am clueless how to begin. :confused: I guess I have writers block, but for physics.:rolleyes:

    Any help on a basic design, and principals behind it would be appreciated. Any links with more info would also be appreciated. I have this weekend to work on it.

    Thanks in advance!
  2. jcsd
  3. May 23, 2007 #2
    You will need some sort of mechanical advantage. This includes something like a lever and/or pulleys. The most simple system would be a see-saw type thing, but have the fulcrum far to one side. You could put the lighter weight all the way on the far side away from the fulcrum, and the heavy weight closer to the fulcrum.

    If you'd like an explanation of a pulley system, please let me know. I could explain, but I have the feeling it wouldn't not be very understandable. I'm not too great at explaining things.
  4. May 23, 2007 #3
    I was also thinking of a pulley system. I like the see-saw idea also. Now I just need the principals behind everything & explanation. Feel free to throw out any other info. Don't mind long explanations. The more I have to mentally digest the better off I'll be later on. Any links to sites explaining this would also be helpful.
  5. May 24, 2007 #4


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    As far as the lever/seesaw situation goes, it's a direct relationship based upon the distance from the fulcrum. A 1kg weight, for instance, if placed 1 metre from the fulcrum will exactly balance a 2kg weight that's 1/2 metre from it on the opposite side.
    Pulleys are a bit more complex. A single pulley will just alter the direction of the force. Adding another in the proper manner will double the force, but require twice the distance of movement. (If not applied for that purpose, it might just again alter the direction. It depends upon how they are arranged.)
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