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Biomechanic problem

  1. Oct 26, 2005 #1
    A 60-N weight is held in the hand with the forearm making a 90° angle with the upper arm as shown in the figure below (note: the arm is held steady and is not moving). The biceps muscle exerts a force Fm that is 3.4 cm from the pivot point "O" at the elbow joint. Neglecting the weight of the arm and hand, what is the magnitude of Fm if the distance from the weight to the pivot point is 30 cm? Draw a free body diagram. http://img442.imageshack.us/img442/4935/free0in.jpg [Broken]

    can any one help me on this one? thanks
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 27, 2005 #2


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    HINT: The sum of the torques about the pivot point must add to zero.
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