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Physics Help

  1. May 19, 2006 #1
    The main muscle responsible for raising an arm is the deltoid. The deltoid muscle connects at the upper end of the shoulder, extends over the upper arm bone (humerus), and attaches near the elbow. Effectively there are three forces involved in raising the arm: (i) the force of the deltoid muscle, Fm, acting at an angle of approximately 13.1o with respect to the negative x axis, (ii) the force of gravity, Fg, acting effectively at the centre of mass of the arm located close to the elbow, and (iii) the force of the shoulder socket, Fs, acting on the humerus effectively along the x axis. Assuming the mass of the arm is 1.92 kg, calculate the magnitude of Fm in Newton.

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  2. jcsd
  3. May 19, 2006 #2
    hey this is just a problem I need desperate help with, for some reason I continually get it wrong.... plz help!
  4. May 19, 2006 #3
    Its okay now.. just figured it out, so simple lol!
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