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Homework Help: Solving for forces/reactions and moments in a complicated frame

  1. Nov 17, 2007 #1
    1.
    http://img337.imageshack.us/img337/520/fic06p090bk7.png [Broken]

    http://img337.imageshack.us/img337/2763/vqc06p090je0.png [Broken]​
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    2. [tex]\sum[/tex]Maboutapoint
    [tex]\sum[/tex]Fy
    [tex]\sum[/tex]Fx




    3. Well firstly i just looked at it as a whole to see if i can figure out any of the reactions at F or B. I am confused about where to and where not to apply that moment of 48 Nm which is replacing the force at A.

    For example when im taking the moment about point F when looking at the system as A WHOLE, should i take into consideration that 48 Nm in the moment equation?

    When im taking it about point E of the WHOLE SYSTEM i do not? or no matter what, I have to add 48 Nm in all moment equations that i make????

    And then please telll me when I DISMEMBER the frame when im looking at the member FCA, is that the only time i take that moment into consideration, or no matter which dismembered part im looking at, I have to take that moment of 48 Nm at point A into consideration in the MOMENT equation I make?
    plzzzzzzz help
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Nov 17, 2007 #2

    Pyrrhus

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    Homework Helper

    In order to solve this problem, simply find the vertical (y-components) of the reactions F and B, by using the whole body, dismember for finding the horizontal (x-components).

    Remember: Moments are Free vectors unlike forces which are sliding vectors.
     
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