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Need help with statics problem

  1. Feb 3, 2007 #1
    1. The problem statement, all variables and given/known data

    a 2.9 lb force P is appplied to the lever which controls the auger of a snowblower. determine the value of alpha knowing that the moment of P about A is counterclockwise and has a magnitude of 17 lb*in

    2. Relevant equations

    3. The attempt at a solution

    i thought i could do it using moment= F*d
    so 17=2.9 tan^-1(alpha)*4.8 see picture attatched
    i did it this way and i was a couple of decimas off so if someone can point me in the right direction thank you

    Attached Files:

    • 3.5.JPG
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    Last edited: Feb 3, 2007
  2. jcsd
  3. Feb 3, 2007 #2
    M = F*d only applies if your moment arm is perpendicular to the line of action of the force.

    This is a 2-D problem so you have 3 equations that you can write down. Once that's done, you can see how to solve for the angle.
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