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Pulley problem

  1. Sep 26, 2004 #1
    Ok, I tried this and even found on this forum that someone asked the same question before, but I tried their advice and the answer was still wrong. The problem is that :
    ---- A window washer pulls herself upward using the bucket-pulley apparatus ...How hard must she pull downward to raise herself slowly at constant speed? The mass of the person plus the bucket is 61.7kg.----

    The advice given on this forum was that since she is moving at a constant speed, the acceleration is zero...so she just needs to pull her (plus the bucket's) weight. I calculated this (W=mg) and got 604.7 N, but the program says I'm wrong. And then it gave a hint : This problem is trickier than it looks. There are two upward forces acting on the girl. One is exerted by the rope on the top of the basket. The other is exerted by the rope on her hands.

    So does anyone have any advice on what to do? Much thanks :eek:)
     
  2. jcsd
  3. Sep 26, 2004 #2
    maybe make it 2N? multiply n times 2.... if the rope goes half way around the pulley, its 2N, at least thats what my program says... try that?
     
  4. Sep 26, 2004 #3
    o like 604.7 times 2? I just tried that and it says it's wrong
     
  5. Sep 26, 2004 #4
    hrm, maybe im doing the wrong one then, sheesh, im gettin so confused lately... sorry i couldnt be of more help
     
  6. Sep 26, 2004 #5
    lol np, thanks for trying tho! :)
     
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