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Homework Help: Forces and Tentions

  1. May 5, 2010 #1
    1. The problem statement, all variables and given/known data

    Two masses, 50 kg and 20 kg, are suspended from a cable system. Determine tentions in cables AB, BC, CD, CE

    2. Relevant equations

    law of cosines
    law of sines

    3. The attempt at a solution

    I tried by solving around point B first and have found Tab and Tbc.
    Are my findings correct? See attache .pdf

    Attached Files:

  2. jcsd
  3. May 6, 2010 #2


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    Gold Member

    One question: Is the angle between CD and CE also 40o?

    One observation: You have drawn three forces acting on the 20 kg mass at C. Tension CE is up and to the right, tension 196 is straight down and tension CD is only to the right. These three forces cannot possibly add up to give zero because the net force will surely have a non-zero component to the right. You need to redraw the diagram using arrows to indicate the direction of each force.

    One suggestion: Draw two separate free body diagrams, one for each mass saying that the sum of all the forces in each diagram must be zero.
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