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Homework Help: Calculating Tension

  1. Dec 8, 2008 #1
    1. The problem statement, all variables and given/known data
    All i was given on the problem was find the tension in each cord in the figure below.

    http://img181.imageshack.us/img181/6417/physicsproblemua3.th.jpg [Broken]

    2. Relevant equations
    Calculate the tension in each cord below.

    3. The attempt at a solution

    T(C) = W

    I know you have to use trigonometry to find the tension in A & B, but without any numbers being given i can't figure anything out.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Dec 8, 2008 #2
    sorry about the image, but it was the only way i could include the diagram. You are able to click it to make it bigger
  4. Dec 8, 2008 #3


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    You have enough to solve it in terms of W.

    Evaluate the vector components in the x,y direction.

    They yield 2 equations in T1 and T2. (In terms of W that is.)
  5. Dec 8, 2008 #4
    Tc = w

    By = Sin(45)*B

    Ay = Sin(30)*A

    Is that all you would have to do to solve the problem?
  6. Dec 8, 2008 #5


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    That would be a no.

    Since the system is static the sum of the y components of the tensions = W
    And since it is balanced left to right then the x components add to 0.
  7. Dec 8, 2008 #6
    so if By+Ay+C = W


    Ax-Bx = 0


    A would be equal to: (w-c-sin(45)B) / sin(30)

    and B is: (w-c-sin(30)A) / sin(45)

    I know there has to be one more part to the solution because even though if you know w, you know c, you still would have one additional variable that's unknown.
  8. Dec 8, 2008 #7
    I don't understand how this website works! =/
  9. Dec 8, 2008 #8


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    There is no C.

    C is W.

    Yielding equations such that

    1/2*T1 + (√2/2)*T2 = W


    (√3/2)*T1 = (√2/2)*T2
  10. Dec 8, 2008 #9


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    If you have questions about homework problems that you need help with, if you post them and explain what you might be having difficulty understanding someone may help you.

    On other areas of the site there are discussions of various topics of interest.
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