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Homework Help: Mechanics question, structure with unknown forces

  1. Nov 23, 2011 #1
    1. The problem statement, all variables and given/known data
    Find force between all members.

    2. Relevant equations
    torque=force x distance

    3. The attempt at a solution
    to use sections as seen in the photo, beyond that no idea how to attempt it. It would helpful if anyone could show me how to get the force out of even 1 member.
  2. jcsd
  3. Nov 24, 2011 #2
    Start by finding ALL external forces in the system, then go onto using them to find the internal forces i.e the forces in the members.
  4. Nov 24, 2011 #3
    using sections though, there seems to be no place to start
  5. Nov 24, 2011 #4
    k well with these topics I have stated the problem in a sufficient capacity AFAIK

    seems to be as many views here as there are on other more popular topics, maybe i should put a dancing cartoon in it

    I normally turn to one of the instructors with these questions, takes them 5 minutes to work through it. But they aren't paid to do it. Neither are you. But I feel it is necessary to exhaust all resources before turning to these people in person. I am trying my best.
  6. Nov 25, 2011 #5
    I just had my lecture on methods of sections this week, so forgive me if I'm a bit rusty.

    A and G have reaction forces due to the external forces being applied to the truss. Take moments about point A or G and solve for Ay or Gy by applying the concept of equilibrium. Once you've got one, you can find the other by using the concept of equilibrium in the Y direction.

    That is your starting point.
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