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Homework Help: Find the angles in a tension on 2 ropes problem

  1. Feb 16, 2010 #1
    1. The problem statement, all variables and given/known data

    A 4.50 kg block of gruyere cheese is suspended as shown. Rope 1 on the left has a tension of 28.3 N; rope 2 on the right has a tension of 40.5 N.
    (a) What is θ1, the angle made by rope 1? (b) What is θ2? State each angle as the positive angle "inside" the triangle the ropes form.
    http://i47.tinypic.com/ivy260.png

    2. Relevant equations

    Newton's second law
    The problem also included these identities:
    http://i47.tinypic.com/mtxv1z.png

    3. The attempt at a solution

    I tried to solve for one of the thetas using the equation for the x-axis
    T1cosθ1+T2cosθ2 = 0

    and then substitute it in the equation for the y-axis *trying* to use the trig identities
    T1sinθ1+T2sinθ2 = mg

    I doubt I'm doing it right but either way I'm way stuck after an hour
    help!please!
     
  2. jcsd
  3. Feb 16, 2010 #2

    rock.freak667

    User Avatar
    Homework Helper

    this one should be T1cosθ1-T2cosθ2 = 0

    yes you are going correct, just take the equation I corrected for you and isolate either T1 or T2 and substitute into the next equation.
     
  4. Feb 16, 2010 #3
    okay sounds good but I'm not solving for T I'm solving for both thetas
     
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