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Homework Help: Acceleration of two pulleys help

  1. Oct 15, 2011 #1
    1. The problem statement, all variables and given/known data

    If a1 and a2 are the accelerations of m1 and m2, respectively, what is the relation between these accelerations?

    2. Relevant equations

    Link to the diagram :
    http://www.webassign.net/serpop/p4-38.gif

    3. The attempt at a solution

    The answer is a1 = 2*a2, but I'm having trouble visualizing/understanding how it was gotten. Is there a specific way to do this?
     
  2. jcsd
  3. Oct 15, 2011 #2
    Get a string or shoe lace and wrap it around a coffee cup. Hold one end of the string still and pull the other end of the string up some distance x, the coffee cup will move x/2.
     

    Attached Files:

  4. Oct 15, 2011 #3
    I get it now; thanks a lot! I can't believe I didn't even see that in the first place.
     
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