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Homework Help: 2d statics truss, joint method

  1. Jan 24, 2012 #1
    1. The problem statement, all variables and given/known data

    Determine force of each member using joint method

    2. Relevant equations
    T = F x D

    3. The attempt at a solution

    Answers are:

    Fab 2465 T
    Fbd 1200 T
    Fbc 1375 C
    Fdc 750 C
    Fde 860 T (This one is what I tried)
    Fce 649 C
    Fac 1922 C

  2. jcsd
  3. Jan 24, 2012 #2


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    I moved this thread to the engineering homework forum as you're more likely to get responses on this type of problem there.

    You might want to forgo using a scanned image of your work, especially one so large, since it makes your post inconvenient to read.
  4. Jan 24, 2012 #3


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    You have the wrong geometry for the slope of member DE...the rise is 20 but the run is 25, not 55....

    Always determine joint support reactions first using the equilibrium equations; then start at the easiest joints next when determining forces using the method of joints. Also be sure to indicate T (force of member on joint pulls away from joint) or C (force of member on joint pushes toward joint).
  5. Jan 24, 2012 #4
    thanks for that, encouraging to know I'm on the right track. Something did seem wrong with the trig
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