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Homework Help: Pulley problem, find total mass where ther is no acceleration

  1. Sep 27, 2010 #1
    1. The problem statement, all variables and given/known data

    you need to see the picture for this one

    http://s861.photobucket.com/albums/ab174/alkaline262/?action=view&current=prob13.jpg


    2. Relevant equations

    f=ma



    3. The attempt at a solution

    i dont really know where to start on this one.

    i have the equations for force

    2T - m2g = -m2a2

    N - m1g = 0

    T = m1a1

    i think i should set a to zero

    2T = m2g
    T=0

    that step doesn't make sense to me, because how can the tension = 0 ?
     
    Last edited: Sep 27, 2010
  2. jcsd
  3. Sep 27, 2010 #2
    are the pulleys negligible?
     
  4. Sep 27, 2010 #3
    yes they are
     
  5. Oct 3, 2010 #4
    bump. i still dont understand this problem when i solve for t is get t = -2g/(1/m1 - 4/m2)

    is that right? what can i do with it ?
     
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