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Homework Help: Help on moment of inertia

  1. Nov 19, 2004 #1
    I need help on a problem, I tried using many equations, what do I do?...

    A m1=13.5kg object and a m2=12.5kg object are suspended, joined by a cord that passes over a pulley with a radius of 10 cm and a mass of 3 kg. The cord has a negligible mass and does not slip on the pulley. The pulley rotates on its axis without friction. The objects start from rest 3 m apart. Treating the pulley as a uniform disk, determine the speeds of the two objects as they pass each other.

    I used the equation to find acceleration...

    a=((m1-m2)g)/(m1+m2+.5mR^2) The .5mR^2 is the moment of Inertia

    After I found the acceleration I found the velocity...

    v=(2a(x/2))^(1/2)

    Please Help
     
  2. jcsd
  3. Nov 19, 2004 #2
    My first thought:
    Use conservation of energy to work for you
    Here the kinetic energy of both masses + potential energy of both masses + rotational energy of the pulley is conserved.
     
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