Torque: A man in a gym is holding an 8.0-kg weight at arm's length, a distance of 0.55 m from his shoulder joint. What is the torque about his shoulder joint due to the weight if his arm is held at 30° below the horizontal?
A. 22 N ? m
B. 2.2 N ? m
C. 4.4 N ? m
D. 13 N ? m
E. 37 N ? m
Answer: E
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