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Pulley question LOL!

  1. Dec 24, 2003 #1
    With amazement, I noticed the 'pulley question' thread with (so far) 42 replies.
    Put a black box around the whole system (plate, pulley, man): You get a black box hanging from a rope. Now what is the tension in the rope?
  2. jcsd
  3. Dec 24, 2003 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Yes, apparently we still haven't exhausted that topic.

    If the system is in equilibrium, then the tension must equal the weight of the system. To accelerate upward, the tension must be greater than the weight.
  4. Dec 25, 2003 #3
    BTW - I was not laughing at the discussers. I was laughing because I had to solve a similar problem some time ago - and came up with a very complicated (and wrong) answer. Then, a guy several years my junior, said "Why not put a black box around this...". He had solved it all nice and simple.
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