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Pulley, Mechanics question

  1. Jul 7, 2011 #1
    1. The problem statement, all variables and given/known data

    Find the reading of the spring balance shown in the figure (see attachment). The elevator is going up with an acceleration of g/10 , the pulley and the string are light weight and the pulley is smooth.

    2. Relevant equations
    F= ma

    3. The attempt at a solution
    Since the elevator is accelerating upwards with a magnitude of 0.98 m/s^2 (g/10) , the acceleration acting on the items in the elevator should be g+g/10 = 10.78 m/s^2.
    By assuming that the 3k load has a relative acceleration of "a", the tension on the string of the 1.5 kg load will be
    16.7 - 3a
    While on the 3kg load it will be
    32.34 + 3a

    I'm sure i have made a blunder somewhere up here, yet i cant seem to find it. How do i further solve the question?
  2. jcsd
  3. Jul 7, 2011 #2
    Maybe it's just me, but I can't locate the attached image
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