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. 7.33 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? 2.88

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. 7.33 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? 2.88

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter3: Motion In Two Dimensions

Section: Chapter Questions

Problem 30P: A point on a rotating turntable 20.0 cm from the center accelerates from rest to a final speed of...

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