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Homework Help: F.B.D. for beam on disabled hoist (confirmation on work needed)

  1. Aug 18, 2010 #1
    1. The problem statement, all variables and given/known data

    Hi guys,

    I'm doing an assignment for college and designing a disabled hoist. I want to complete FBDs on the top beam especially. Can anyone help answer whether the work i've done is correct?

    2. Relevant equations

    the equations I used were the sum of all force = 0

    and for the bending stress that the shear force = dm/dx

    3. The attempt at a solution

    Please see the two pictures attached for my attempts at (very quickly) drawing what i believe to be the correct solution. I'm taking the hwole thing to be static, as in the linear actuator is creating a force opposing the Load F. I would really appreciate some feedback, because I find F.B.D's hard to grasp, and I could be totally wrong!

    Thanks
    L
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

    Attached Files:

  2. jcsd
  3. Aug 19, 2010 #2
    Can anyone shed any light on this?
     
  4. Aug 19, 2010 #3

    vela

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    What about the weight of the beam?
     
  5. Aug 19, 2010 #4
    How would I incorporate w into a shear diagram? Would it effect it? I understand w is another force acting on the beam and will put it in the top FBD, but I don't know what to do for the Shear and bending diagrams.

    Thanks
     
  6. Aug 19, 2010 #5

    vela

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    It's just another force. Treat it like you did the other forces.
     
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