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Homework Help: Double pulley system problems

  1. Oct 23, 2012 #1
    1. The problem statement, all variables and given/known data
    Question 2

    2. Relevant equations

    3. The attempt at a solution
    Well I tried to draw a diagram but I don't really know where to start tbh, I also can't my head around how 1200N of force only provides 600N worthof acceleration
  2. jcsd
  3. Oct 23, 2012 #2
    Your link is inaccessible. You have to change the settings for the file so it can be seen publicly.
  4. Oct 23, 2012 #3
    Sorry I fixed it now
  5. Oct 23, 2012 #4
    For starters, the lower pulley 'splits' the force the platform is pulling down with. Also, the drum is pulling on both the cable and the platform it's connected to.
  6. Oct 23, 2012 #5
    This is what I have so far although it still seems wrong
  7. Oct 23, 2012 #6
    The values 1.8kN and 1.2kN are spot on. I don't know where you got 0.9kN and 2.1kN, though. The tension 1.2kN from the drum should cause a chain of action-reaction pairs along every segment of rope.
  8. Oct 23, 2012 #7
    I see what I did wrong now, thanks for the help
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