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Homework Help: Pivot Problem

  1. Oct 29, 2011 #1
    Static Equilibrium Problem

    1. The problem statement, all variables and given/known data
    A uniform bar of length 16 m and mass 8 kg is
    attached to a wall with a hinge that exerts a
    horizontal force Hx and a vertical force Hy on
    the bar. The bar is held by a cord that makes
    a 90 degree angle with respect to the bar and 45 degree
    with respect to the wall.
    What is the magnitude of the horizontal
    force Hx on the pivot? The acceleration of
    gravity is 9.8 m/s2 .
    Answer in units of N

    2. Relevant equations

    3. The attempt at a solution
    I actually have no idea what I'm doing in this question. This chapter I do not get.

    Attached Files:

    Last edited: Oct 30, 2011
  2. jcsd
  3. Oct 30, 2011 #2
    It takes time, try studying worked out examples.

    Attached Files:

  4. Oct 31, 2011 #3
    for Hx, why isn't x component of the rod included?
  5. Oct 31, 2011 #4
    There are only two forces in the x direction that act on the bar, a piece of T and the force acting on the bar at the pivot I labeled F_x.

    Good luck.
  6. Oct 31, 2011 #5
    Yes yes but i dont understand why x component of Fg is left out though
  7. Oct 31, 2011 #6
    What is Fg? Is that mg? If so mg acts in the y direction.
  8. Oct 31, 2011 #7
    I got it. I got confused with this Fg cuz the rod was slanted and somehow mistaken it that the rod was on the incline -_- thank u mate :)
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