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Statics problem - too many unknowns?

  1. Apr 20, 2013 #1
    1. The problem statement, all variables and given/known data

    See attachment. Find the tension in the string that is keeping this weird contraption together. The left stick has mass m, the right stick has mass 2m. m, θ and L are known quantities.

    2. Relevant equations

    3. The attempt at a solution

    Tried starting with the right stick since there's less unknowns there. There's five forces acting upon it I think. By, Bx, T, Cy and 2mg.

    I got these equilibrium equations:

    By + Cy - 2mg = 0
    T + Bx = 0
    Cy*0.5cosθ - By*0.5cosθ - Bx*0.5sinθ = 0

    Not sure where to go from here. Having a REALLY tough time getting an intuition for statics.

    Attached Files:

  2. jcsd
  3. Apr 20, 2013 #2


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    2017 Award

    Staff: Mentor

    You could add the left stick.
    This will give 3 equations again, but just 2 additional unknown parameters. In total, you get 6 unknown parameters and 6 equations.
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