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Homework Help: Equilibrium Question

  1. Nov 11, 2003 #1
    Misako wishes to measure the strength of her biceps muscle by exerting a force on a test strap. The strap is 28 cm from the pivot point at the elbow, and her biceps muscle is attached at a point 5 cm from the pivot point. If the scale reads 18 N when she exerts her maximum force, what force is exerted by the biceps muscle?

    See attachment for a diagram. Please help me solve this problem.
     

    Attached Files:

  2. jcsd
  3. Nov 12, 2003 #2

    jamesrc

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    Gold Member

    Try summing the moments about the elbow. Since the arm is in equilibrium, they should sum to zero; that is how to find the unknown bicep force.
     
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