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Rod on a pivot: Linear acceleration and reaction forces

  1. Jul 17, 2012 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations
    r * [itex]\alpha[/itex] = atan
    r * [itex]\omega^2[/itex] = arad

    3. The attempt at a solution
    arad = (L/2)(3g/L) = 3g/2
    atan = (L/2)(3g/2L) = 3g/4
  2. jcsd
  3. Jul 17, 2012 #2

    Doc Al

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    Staff: Mentor

    How did you get this?
    Looks OK. (But don't forget the proper signs of the components.)
  4. Jul 17, 2012 #3
    I got arad = 3g/2 by multiplying r by ω2.

    EDIT: It was actually -3g/2.

    Going onto the reaction forces, I thought it was just R = ma, but apparently that's not the case...

    Re-EDIT: Got it. I just needed to add the negative signs.
    Last edited: Jul 17, 2012
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