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Homework Help: Forces Problem - Tension

  1. Oct 13, 2007 #1
    1. The problem statement, all variables and given/known data

    A window washer pulls herself upward using the bucket-pulley apparatus:


    The mass of the person plus the bucket is 63 kg.

    (a) How hard must she pull downward to raise herself slowly at constant speed?

    2. Relevant equations

    F = m(a)

    3. The attempt at a solution

    I figured that since she wants to raise herself at constant speed, that makes her acceleration equal to zero. Which means Fnet=0=Ftension-Fgravity, so Ftension=Fgravity. F gravity=9.8(63)=617.4 N, but it says I have the wrong answer.

    Thanks in advance for the help.
  2. jcsd
  3. Oct 13, 2007 #2


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    Science Advisor
    Homework Helper
    Gold Member

    you need to draw a good free body diagram. Isolate the woman , bucket and both cords by drawing a circle around them that cuts thru the cords, and identify all forces acting.
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