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 13.5 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 1490 N, and its effective perpendicular lever arm is 3.45 cm. Find the magnitude of the angular acceleration a of the weight. 9.9 rad/s? How much work W is done if the leg rotates through an angle of 25.0° with a constant force exerted by the muscle? W = 7.21 Question Credit: OpenStax College Physics

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 13.5 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 1490 N, and its effective perpendicular lever arm is 3.45 cm. Find the magnitude of the angular acceleration a of the weight. 9.9 rad/s? How much work W is done if the leg rotates through an angle of 25.0° with a constant force exerted by the muscle? W = 7.21 Question Credit: OpenStax College Physics

University Physics Volume 1

18th Edition

ISBN:9781938168277

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

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

Chapter12: Static Equilibrium And Elasticity

Section: Chapter Questions

Problem 37P: To get up on the roof, a person (mass 70.0 kg) places 6.00-m aluminum ladder (mass 10.0 kg) against...

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