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Homework Help: Help ly need someone to help me check pulley problem

  1. Jan 24, 2010 #1
    Help urgently need someone to help me check pulley problem

    Two masses are connected over a small pulley using a light string. The mass on the left is 1.00 kg and the mass on the right is 6.50 kg. The mass on the right is a distance 2.00 m above the ground. The system is released from rest as shown in the animation below.



    What is the speed of each object just before the mass on the right strikes the ground?
    ________________m/s

    Attempt
    mgh + (mv^2)/2 + (Mv^2)/2 = mgh + (mV^2)/2 + (Mv^2)/2
    (6.5)(9.8)(2) + 0 + 0 = 1(9.8)(2) + (6.5v^2)/2 + V^2/2
    (6.5)(9.8)(2) = 1(9.8)(2) + (7.5v^2)/2

    If i solve for this will i get the right answer?
     
  2. jcsd
  3. Jan 24, 2010 #2
    Re: Help urgently need someone to help me check pulley problem

    Yes. You switched some symbols in the first line wich should be:

    mgh + (mv^2)/2 + (Mv^2)/2 = Mgh + (mV^2)/2 + (MV^2)/2

    but you substituted all the right constants anyway.
     
  4. Jan 24, 2010 #3
    Re: Help urgently need someone to help me check pulley problem

    thanks
     
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