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Homework Help: Another Moment Question

  1. Feb 1, 2007 #1
    I just realized this is in the wrong place..Move it to intro to physics please. Sorry

    1. The problem statement, all variables and given/known data
    Using Cartesian vector analysis determine the moment of the three forces about the base of the column at A. F1 =400i +300j+120k


    2. Relevant equations

    The [tex]x[/tex] represents "cross"..i dont know the latex for it

    [tex]M_a = r x F[/tex] (summation)

    3. The attempt at a solution

    I keep getting the wrong answer and I think it has something to do with the point E. What does this have to do with anything?

    What I am doing is summing all the forces crossed with their distances.

    [tex]r_B={12k}N[/tex]
    [tex]r_{F3}={0i-j+8k}N[/tex]

    So [tex]M_A = (r_B x F_1) + (r_B x F_2) + (r_{F3} x F_3)[/tex]
     

    Attached Files:

    Last edited: Feb 1, 2007
  2. jcsd
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