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Find the maximum tension in the rope problem

  1. Sep 30, 2009 #1
    1. The problem statement, all variables and given/known data

    A horizontal rope pulls a 10kg wood sled across frictionless snow. A 5.0kg wood box rides on the sled. The coefficient of static friction for wood on wood is \mu_s=0.5.

    What is the largest tension force for which the box doesn't slip?
    2. Relevant equations


    3. The attempt at a solution

    So far I've got a picture and a free body diagram, with 3 total forces: Gravity defining down, normal force pointing up, and static friction pointed opposite the direction of motion.

    I tried setting T equal to static friction but I got the wrong answer.

    Can someone talk me through the problem so I know what I'm missing? Thanks.
  2. jcsd
  3. Sep 30, 2009 #2


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    Homework Helper

    Show your calculations and answer. Then only we are in a position to tell where you went wrong.
  4. Sep 30, 2009 #3


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    Science Advisor
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    Gold Member

    Is this is a free body diagram of the forces acting on the sled, or on the box, or on the sled - box system? You'll need 2 free body diagrams to solve for T. Hint: The box and sled are both accelerating at the same rate.
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