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Homework Help: Tension and Inclines

  1. Sep 24, 2007 #1
    A 1.2 kg mass, m2, on a 30.1° incline is connected to a 5.4 kg mass, m1, on a horizontal surface. The surfaces and the pulley are frictionless. If F = 20.8 N, what is the magnitude of the tension in the connecting cord?

    I created a FBD for both masses
    X: F+T-mg*sin(theta)=m2a
    Y: N-mg*cos(theta)=0

    X: F=m1a
    Y: N-mg=0

    I derived this equation


    Is this equation on the right path?
    Last edited: Sep 24, 2007
  2. jcsd
  3. Sep 24, 2007 #2


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    If F is pulling m2 up the incline, then T acting on m2 will have the opposite sign, and T (between m1 and m2) will be acting on m1.
  4. Sep 24, 2007 #3
    Well I was able to solve this, but there was a lot of dispute as to how to derive the equation.

    I'm not sure what was wrong with my derviation, but the answer is 12.2 N.
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