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Homework Help: Finding forces on a Truss

  1. Mar 3, 2009 #1

    I have a test after 4 hours and I really need to know how to solve this :S
    I tried my best and threw 4 pages of scratch papers already !!!
    Please help me...
    I know im doing it wrong, I tried and tried but it did not work .. Im really frustrated I feel like im going to fail the test -.-

    The angles are not given so I have no idea how find these forces .. and the vertical force of 100Kn, how is it distributed to both sides ??!

    This is all I can do until now :

    http://img7.imageshack.us/img7/3943/image169g.jpg [Broken]

    Please help me
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Mar 3, 2009 #2


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    Probably too late for your test, but always solve for the support reactions first using the equilibrium equations; I assume one support is pinned and the other is a roller support. Then, after solving for the x and y components of the reactions at the pin, and the y component of the reaction at the roller, then look at the joints to solve for the member forces, again using the equilibrium equations. Your forces at the joints are not correct.
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