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Homework Help: Help please -- Free body diagram for a weightlifter?

  1. Oct 25, 2015 #1
    1. The problem statement, all variables and given/known data

    A weightlifter stands up at constant speed from a squatting position while holding a heavy barbell across his shoulders. Draw the free body diagram of the lifer using Fg, normal force, and force by barbell
    2. Relevant equations

    Fnet=0 ?
    3. The attempt at a solution
    I tried drawing the normal force up and the force of gravity down with equal magnitude with each other. I also placed the force by barbell the same direction as the force of gravity with less magnitude than the force of gravity of the lifter. It says it is wrong. What am I doing wrong? I am pretty sure the force by barbell vector is not correct but i do not know how to fix it
  2. jcsd
  3. Oct 25, 2015 #2


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    What is the net force on the lifter, according to your diagram? Is it zero? Sounds like it is not.
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