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Homework Help: Free Body Diagram for simply supported beam

  1. Jul 25, 2012 #1
    1. The problem statement, all variables and given/known data

    As shown in the attachment, a free body diagram (FBD) must be drawn

    2. Relevant equations

    sum of horizontal force = 0
    sum of vertical force = 0

    3. The attempt at a solution

    1. Forces F1 and F2 appear exactly as they are in the FBD

    2. At point A, there is an outward horizontal force : <----- A, to counteract F2

    3. At point B, there is an upward force to counteract F1 :


    However, I think I have done something wrong. Any help would be greatly appreciated!

    Attached Files:

    • beam.JPG
      File size:
      9.6 KB
    Last edited: Jul 25, 2012
  2. jcsd
  3. Jul 25, 2012 #2


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  4. Jul 25, 2012 #3
    That's what I thought too, because it's pin supported, there should be a horizontal and vertical force acting at point A. But I attached another picture that shows where to draw the forces. And there's only one force that can be drawn at point A.

    Also all the circles don't have to have forces drawn on them, so I left the middle circle.

    Attached Files:

  5. Jul 25, 2012 #4


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    Why not draw it at an angle representing the resultant of the horiz and vert forces ?
  6. Jul 26, 2012 #5
    ok thank you Cwatters and phanthomJay. I found it was possible to more than one force on one circle.
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