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Homework Help: Pin jointed frame question

  1. Jul 14, 2011 #1
    The problem statement, all variables and given/known data
    [PLAIN]http://img847.imageshack.us/img847/1704/pinjointed.png [Broken]
    Calculate the reactions at A and E and the forces in all members.

    The attempt at a solution

    At a loss regarding the reactions, tried equating vertical and horizontal.
    As for the members I guess its just a case of working from the reaction values and using sin and cos but also can't get my head around this.

    Any methods/pushes in the right direction much appreciated.
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Jul 14, 2011 #2
    In 2-dimensional work, as this one is, how many equations are there of static equilibrium? And what are they?
  4. Jul 14, 2011 #3
    sum of v=0 and sum of horiz=0
  5. Jul 14, 2011 #4


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    Don't forget the sum of the moments = 0.
  6. Jul 16, 2011 #5
    I have VA as 10 but cant work out the other two, the equation would suggest that HE-HA+5=0 which leaves two unknowns so i'm stuck with that.
  7. Jul 19, 2011 #6


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    You are forgetting about the 3rd equation of equilibrium alluded to in the prior responses.
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