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Homework Help: Physics problem help

  1. Oct 1, 2005 #1
    I am working on a physics problem which states:
    A person doing a chin-up 700N exclusive of the arms. During the first 25.0 cm of the lift, each arm exerts an upward force of 355 N on the torso. If the upward movement starts from resdt, what is the person's velocity at this point?

    This is probably very basic, but I am having trouble with this whole energy, work, force, tension thing.
     
  2. jcsd
  3. Oct 2, 2005 #2

    hotvette

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    Explain what you've tried and what equations are relevent. Have you drawn a free body diagram and labeled the forces?
     
  4. Oct 3, 2005 #3
    You should have these formulas, derive an expression for final velocity and then plug in your numbers

    Kf – Ki + Uf – Ui = Wnc
    1/2mVf-1/2Vi+mgyf-mgyi=Wnc
     
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