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To develop muscle tone, a woman lifts a 3.30 kg mass held in her hand. She...

To develop muscle tone, a woman lifts a 3.30 kg mass held in her hand. She uses her biceps muscle to flex the lower arm through an angle of 60.0°. Ignore gravity. (a) What is the angular acceleration, in rad/s2, if the mass is 24.0 cm from the elbow joint, her forearm having a moment of inertia of 0.250 kg · m2, and the muscle force being 830 N at an effective perpendicular lever arm of 2.90 cm? (b) How much work, in joules, does she do?

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