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Homework Help: Torque and Massless beam with Two Objects

  1. Nov 17, 2011 #1
    Torque and Massless beam with Two Objects!!

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

    A massless beam is supported only at one point, called the pivot point, as shown in the diagram. A block with mass m1 sits at the left end of the beam, a distance L1 from the pivot point. A block with mass m2 sits at the right end of the beam, a distance L2 from the pivot point. L2 > L1. Calculate all torques about the pivot point, remembering that positive is anti-clockwise.
    Select Yes, No, Less than, Equal to, or Cannot tell.

    (a)If m1 = m2, will the masses have an angular acceleration?

    (b)Given particular values of L1 and L2, does the angular acceleration depend only on m1 / m2 ? (If it depends on the actual values of m1 and m2, put 'no'.)

    (c)Is there a net (non-zero) torque?

    (d)Given particular values of m1, m2, and L1, is it always possible to choose L2 (with L2 > L1) such that the masses have no angular acceleration?

    3. The attempt at a solution
    I tried yes yes cannot tell and yes..

    where did I go wrong ?
    out of six tries this is my last one.. Please help .. PLEASE.
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Nov 18, 2011 #2
    Re: Torque and Massless beam with Two Objects!!

    Start by drawing a diagram of the situation; label all masses, distances and forces.
    If you're short on time I'd take a close look at the wording of part (d) specifically ;)
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