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Dynamics- No Friction

  1. Oct 8, 2013 #1
    1. The problem statement, all variables and given/known data

    Find the normal force in terms of g, m, θ and α. There is no friction. a=0, θ≠α

    See first attachment for diagram

    2. Relevant equations


    3. The attempt at a solution

    I drew a free body diagram including the forces; normal, mg, and |FA| (See second attachment) I'm not sure if this is complete as I don't know where α would be part of it.

    However I did start with this,

    mg=η/cosθ (eq'n 1)

    |FA|-mgsinθ=max (sub eq'n 1 in)

    Attached Files:

  2. jcsd
  3. Oct 8, 2013 #2
    look at the given information carefully. It tells you that acceleration, a=0, that is the body is in equilibrium so all the force balance out.
    So essentially Fnet=0

    Balance out forces in both directions. And remember that FA acts at an angle α (alpha), so appropriately use FA*cos(α) or FA*sin(α) and balance out the forces.

    I hope it helps
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