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Homework Help: Work done by three forces

  1. Sep 22, 2012 #1
    1. The problem statement, all variables and given/known data
    The three ropes shown in the bird's-eye view of the figure (Figure 1) are used to drag a crate 3.2 across the floor.How much work is done by each of the three forces? Then the picture is Force one is 600N 20o above the x-axis force two is 410N 30o below the x-axis and force 3 is 650N along the x-axis in the negative direction

    2. Relevant equations

    3. The attempt at a solution
    So I plugged the each of the numbers into the equation and got work from force one to be 600*3.2*cos20=1804J, the work from force two to be 410*3.2*cos30=1136 and work from force three equals 650*3.2*cos180=-2080
    This seems really easy but when I plug it into the website it says it's wrong and gives no feedback I can't figure out what I'm doing wrong
  2. jcsd
  3. Sep 22, 2012 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Your work looks good to me. Sometimes they are fussy about the number of significant figures.
  4. Sep 22, 2012 #3
    This site doesn't care about significant figures but it tends to be unclear about what it's looking for I just wanted to make sure I wasn't making any small mistakes
  5. Sep 22, 2012 #4
    Just realized I was supposed to answer in kJ instead of J
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