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Tension in Chain in Multiple Pulley Station

  1. Jun 12, 2006 #1
    This is for a graded online homework due at 11. I got everything else on it right, but this is giving me trouble for some reason. We get to resubmit answers once, and my first answer of 215.6N was wrong

    Question: The pulley system in the figure is used to lift a crate of mass m = 44 kg. Note that a chain connects the upper pulley to the ceiling and a second chain connects the lower pulley to the crate. Assume that the masses of the chains, pulleys, and ropes are negligible. Determine the tension in each chain when the crate is being lifted with constant speed.

    Diagram: https://jshare.johnshopkins.edu/amian3/public_html/pulleysystem.gif?uniq=-25jd0a

    Initially, I figured the weight of the object would be distributed by the 2 tensions to the ceiling so I answered mg/2 which was 44*9.8/2 = 215.6N.

    If anyone could help me out it'd be much appreciated, thank you.
  2. jcsd
  3. Jun 12, 2006 #2
    Figured it out. It's just m*g = 431.2N. The Tension of the rope to the ceiling and the pulling force cancel out b/c its in equilibrium, so you just have the tension force going upward and mg going down so mg - T = 0, mg = T.
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