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Calculate the torque about the elbow

  1. Oct 24, 2004 #1
    Athletes sometimes do an exercise called "curing weights." This exercise consists of holding the arm from the shoulder to the elbow steady and snug against the body while pulling a weight to the chest. Calculate the torque about the elbow caused by a 40 pound weight that makes an angle of 55 degrees with respect to the body.

    i know the formula is torque= F s sin()
    I found the force by coverting pound 40pounds/2.2046kg= 18.144kg x 1000g= 18144 g x 9.81m/s =177993force

    torque= F s sin(55)= (18144g)(9.81 m/s2) (s) sin(55)=

    but what is s they don't give me the s. do i have to use other formula? am confused? please help
  2. jcsd
  3. Oct 25, 2004 #2
    I suppose you need to estimate the length of an ordinary arm and calculate the torque accordingly.
  4. Oct 25, 2004 #3
    Seems to me, if they don't give you a length of the forearm, then you have solved it completely with s left as a variable. Although, I would probably express the force as 178 KN, but thats just me.
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