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Homework Help: Newtons 3rd Law

  1. Dec 2, 2009 #1
    1. The problem statement, all variables and given/known data

    Two masses are places in a frictionless pulley system. Solve for the acceleration and tension force. )its a pullz question and the mu=0.1

    2. Relevant equations
    So i know that Fg=MG
    How can i solve this question? how come Fnet=Ft came out of nowhere?

    3. The attempt at a solution
  2. jcsd
  3. Dec 2, 2009 #2
    This seems to be an Atwood machine problem, although I don't understand the last part of the problem statement.

    You will want to set up the equations of motion for each mass. For mass m(1):

    F1 = m(1)*a = T -m(1)*g = 0

    For m(2):

    F2 = m(2)*a = m(2)*g - T = 0

    To solve for tension, first solve the two equations for acceleration (a) and then set them equal to each other. Then solve for T. For acceleration, solve the equation for T and set them equal to each other. Then solve for a.
  4. Dec 2, 2009 #3
    well the mu is 0.1 and i dont know were did you get the m and t-m
  5. Dec 2, 2009 #4
    Here's where I'm getting confused. What is mu?
  6. Dec 2, 2009 #5
    well it looks like a U,its the coefficent of friction, its grade 11 physics
  7. Dec 2, 2009 #6
    But you said the system was frictionless.
  8. Dec 2, 2009 #7
    shoot, my bad i was looking at the wrong question. sorry
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