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Homework Help: Tension Problem

  1. Sep 22, 2007 #1
    1. The problem statement, all variables and given/known data
    A block of mass m1 = 6.75 kg on a frictionless plane inclined at angle = 30.3° is connected by a cord over a massless, frictionless pulley to a second block of mass m2 = 2.07 kg hanging vertically (Fig. 5-54). (a) What is the acceleration of the hanging block (choose the positive direction up)? (b) What is the tension in the cord?


    2. Relevant equations
    Fynet= T-m2g= m2a aka T=m2g+m2a
    Fxnet=m1g(sin)-T=m1a

    when these two are put together it is, a=(m1g sin - m2g)/(m1+m2)



    3. The attempt at a solution
    So I used the equations above and first found acceleration to be -1.914m/s squared and then I used the acceleration and plugged it back into the problem to find T and I got it to be 16.32 N, these answers are wrong and I don't know what I did wrong. Can someone help me please?
     
  2. jcsd
  3. Sep 22, 2007 #2
    Last edited: Sep 22, 2007
  4. Sep 22, 2007 #3
    From the free body diagram... when you extend out the normal force and make a triangle with the force of gravity, the sin is to find the x-component of the triangle
     
  5. Sep 22, 2007 #4
    the normal force counter acts only the gravity ?

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    Correct me if I am wrong.
    http://ghazi.bousselmi.googlepages.com/présentation2
     
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