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Homework Help: Help! Cheese Problem!

  1. Feb 18, 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.

    2. Relevant equations

    It is suggested we use these: http://i47.tinypic.com/mtxv1z.png

    3. The attempt at a solution

    I've got the x axis as T1cosθ1+T2cosθ2=0
    and the y axis as T1sinθ1+T2sinθ2=mg

    And now I'm stuck...Please help!
  2. jcsd
  3. Feb 18, 2010 #2


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    Science Advisor
    Homework Helper

    You are given T1 and T2, right? So you have two equations, which you can use to eliminate θ2 and solve for θ1. For this you will probably need the given identities (for example, you will get θ2 = arccos(... θ1 ...)
  4. Feb 18, 2010 #3
    Okay, so if I use T1cosθ1+T2cosθ2=0 and plug in the values for T1 and T2 and solve for θ1 I get arccos(1.43cosθ2) and I'm lost again.

    Do I set this equal as in: arccos(1.43cosθ2)=arcsin(sqrt((1-arccos(1.43cosθ2))^2)))

    and then solve?
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