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Homework Help: Truss Problem

  1. May 21, 2008 #1
    1. The problem statement, all variables and given/known data
    A 4000lb uniformly weighted crate is attached by light inextensible cables to the trus show below. Simply determine the reaction at A and E of the truss show below

    Figure 1 attachment

    2. Relevant equations
    I used the Moment arm equation of M = F*Distance

    3. The attempt at a solution

    I know how to find out the Fx and Fy force of A and E, but im having trouble determine the Fx and Fy force of B D C

    Attached Files:

    Last edited: May 21, 2008
  2. jcsd
  3. May 21, 2008 #2


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    Science Advisor
    Homework Helper
    Gold Member

    Hi, kennyvs, welcome to PF!
    The problem asks you to determine the reactions at A and E, which you know how to find. There are no supports at B, D, and E, therefore, there are no reactions at those joints. Are you trying to take this problem one step further by determining the member forces? Each of the joint forces must sum to 0. For example, at joint D, the cable exerts a 2000 pound downward pull on the joint, so the member BD must exert an upward pull of 2000 pounds on that joint. But I'm not sure what you are trying to do.
  4. May 21, 2008 #3
    I think i got what i need to complete the assignment. Initially I dont know what the force at B D C are, but knowthnx to your reply ^^ now i can find moment A with the force from joint B, D, C. Thnx
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