While exercising in a fitness center, a man lies face down on a bench and lifts a weight with one lower leg by contracting the muscles in the back of the upper leg. The weight has mass 10.5 kg, and is a distance of 28.0 cm from the knee joint. The moment of inertia of the lower leg is 0.900 kg m² , the muscle force is 1410 N, and its effective perpendicular lever arm is 3.40 cm. Find the magnitude of the angular acceleration a of the weight. a = rad/s? How much work W is done if the leg rotates through an angle of 15.0° with a constant force exerted by the muscle? W = J

While exercising in a fitness center, a man lies face down on a bench and lifts a weight with one lower leg by contracting the muscles in the back of the upper leg. The weight has mass 10.5 kg, and is a distance of 28.0 cm from the knee joint. The moment of inertia of the lower leg is 0.900 kg m² , the muscle force is 1410 N, and its effective perpendicular lever arm is 3.40 cm. Find the magnitude of the angular acceleration a of the weight. a = rad/s? How much work W is done if the leg rotates through an angle of 15.0° with a constant force exerted by the muscle? W = J

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter11: Angular Momentum

Section: Chapter Questions

Problem 72P: An ice skater is preparing for a jump with turns and has his arms extended. His moment of inertia is...

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