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Homework Help: Moving down on a frictionless plane

  1. Oct 14, 2008 #1
    1. The problem statement, all variables and given/known data
    A shipping container is hauled up a roller ramp that is effectively frictionless at a constant speed of 2.10 m/s by a 2250 N force that is parallel to the ramp. If the ramp is at a 24.7° incline, what is the container's mass?


    2. Relevant equations
    Fx = mg sin(theta)
    F = ma
    A = Fx / m


    3. The attempt at a solution
    I tried the equations above but I'm unsure if I'm doing this correctly ...
    2250/9.8 = 229.592
    229.592sin(24.7)=95.9389
    2250/95.9389=23.4524 kg
     
  2. jcsd
  3. Oct 14, 2008 #2
    Yes I think you are doing it correctly.

    Since it is at a constant speed that means no acceleration hence no Fnet (N2)

    So the force that is pushing it up should be equal the the x component of gravity.

    Fgx=Fapplied

    mgsin(theta)=Fapplied
     
  4. Oct 14, 2008 #3
    these problems are on the Kinematic Books website - that answer ended up being incorrect - it doesn't tell you what the correct answer is

    I'm not sure what I did wrong ... I tried that problem 3 times
     
  5. Oct 14, 2008 #4
    these problems are on the Kinematic Books website - that answer ended up being incorrect - it doesn't tell you what the correct answer is

    I'm not sure what I did wrong ... I tried that problem 3 times
     
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