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 11.5 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 1470 N, and its effective perpendicular lever arm is 3.45 cm. Find the magnitude of the angular acceleration a of the weight. a = 25.9918 rad/s2 Incorrect How much work W is done if the leg rotates through an angle of 10.0° with a constant force exerted by the muscle? W = 8.1728 Incorrect 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 11.5 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 1470 N, and its effective perpendicular lever arm is 3.45 cm. Find the magnitude of the angular acceleration a of the weight. a = 25.9918 rad/s2 Incorrect How much work W is done if the leg rotates through an angle of 10.0° with a constant force exerted by the muscle? W = 8.1728 Incorrect Question Credit: OpenStax College Physics

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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