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Homework Help: Forces help

  1. Aug 26, 2009 #1
    1. The problem statement, all variables and given/known data

    a mass (m1) on a smooth horizontal surface, connected by a thin cord that passes over a pulley to a second block (m2), which hangs vertically.

    If the acceleration is .098 m/s^2 and m1 is 1.0 kg how much must m1 must be to keep it at this acceleration

    2. Relevant equations

    net force = ma

    3. The attempt at a solution

    i got 99 kg
    please help me... it's really late at night and I'm tired...
  2. jcsd
  3. Aug 26, 2009 #2


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    Homework Helper

    Do what you always should do with mechanics problems: draw free-body diagrams, then write out Newton's second law for each body. Remember that the tension in a massless rope hung over a massless pulley is constant throughout the rope.
  4. Aug 26, 2009 #3
    Draw free-body diagrams of each object and the forces acting on them. If two objects are connected by a single string, then they have the same tension.
  5. Aug 26, 2009 #4
    Do you know if I got it right?
  6. Aug 26, 2009 #5
    your asking for m1? It's already given. Am I right?
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