What is the Torque on an Outstretched Arm with a 21.5 N Weight?

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To determine the torque on an outstretched arm holding a 21.5 N weight, the relevant distances from the elbow to the weight and the shoulder must be accurately measured. The torque equation T = rF is applied, where r is the distance from the pivot point (elbow) to the point of force application (weight). The user is confused about the correct placement of the center of torque, initially choosing the shoulder instead of the elbow, which affects the calculations. The equation used to balance torques includes multiple segments of the arm, but the user struggles with the correct application of distances and forces. Clarifying the pivot point and ensuring accurate distance measurements will resolve the confusion in calculating the torque.
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Homework Statement


A 21.5 N weight is held in the outstretched hand of a person with a shoulder-to-elbow length of 33.5 cm and an elbow-to-wrist length of 23.0 cm. The center of the weight is 6.5 cm from the person's wrist. Determine the magnitude of the torque about the elbow produced by the weight.


Homework Equations


T=rF


The Attempt at a Solution


T1 - Elbow
T2 - Wrist
T3 - Hand w/weight
T1D1 + T2(D1+D2) - T3(D1 + D2 + D3) = 0
T1 = -T2(.565m) + T3(.63)/.335

I know I am doing something wrong with the torques but I can't figure out what? I thought I just put in 21.5 N.
 
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I forgot to mention that I put my center of torque at the shoulder
 
Can I not have the center of torque there?
 

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