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Tension of 2 cables supporting one object

  1. Oct 14, 2010 #1
    1. The problem statement, all variables and given/known data

    A 1,000kg steel beam is supported by 2 ropes. What is the tension in each?

    Rope 1 on the left is -20 degrees from vertical and rope 2 on the right is 30 degrees from vertical, making a V shape, the tops being connected to a ceiling.

    2. Relevant equations

    Not sure other than converting kg's to Newtons at some point and probably using trig.

    3. The attempt at a solution

    My friends and I think that the x components of both triangles formed have to add up to 0 and the y components of the 2 triangles need to add up to 1,000 kg.

    rope 1=r1
    rope 2=r2

    (r2)sin30+(r1)sin20=0

    (r2)cos30+(r1)cos20=1000kg

    we tried solving for r1 in the first equation then substituting that into r1's spot in the second equation but that didn't work. any tips would be appreciated.. we've been trying to figure this out for the past hour
     
  2. jcsd
  3. Oct 14, 2010 #2
    your method is right... and the way to solve is right too
    T1*sin20=T2*cos30

    (T2)cos30+(T1)cos20=1000*9.8 (here's your mistake you didnt multiply by g)
     
  4. Oct 20, 2010 #3
    awesome, thank you
     
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