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Two Connected Masses

  1. Mar 23, 2010 #1
    1. The problem statement, all variables and given/known data

    Two masses are tied together by a string over a massless pulley so that they can both move vertically. Their masses are 1 kg and 3 kg. What is the acceleration of the 1 kg mass?

    2. Relevant equations


    3. The attempt at a solution

    I have the 3 kg mass's summation of forces as ma-T. (In my free body diagram, the 3kg mass is the one closest to the pulley.)

    The 1 kg mass's summation of forces are mg-T.

    I'm unsure if my diagram is correct and I don't know where to go from here.
  2. jcsd
  3. Mar 23, 2010 #2


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    Welcome to PF!

    Hi Juggernaut06 ! Welcome to PF! :smile:
    No, both wrong :redface:

    both masses have both a and mg.

    And of course a is equal (and opposite) for both. :wink:
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