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 Consider the objects labeled A, B, C, and D shown in the figure. 米上。 Each object is composed of identical thin sticks of uniformly distributed mass 3.95 kg and length 0.241 m. What are the moments of inertia IA, IB, Ic, and Ip of the objects about a rotation axis perpendicular to the screen and passing through the black dot displayed on each object? IA = 0.4 kg-m? Iв 3 0.5 kg-m2 Ic = 1.6 |kg•m² Ip = 1.8 kg-m?

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 Consider the objects labeled A, B, C, and D shown in the figure. 米上。 Each object is composed of identical thin sticks of uniformly distributed mass 3.95 kg and length 0.241 m. What are the moments of inertia IA, IB, Ic, and Ip of the objects about a rotation axis perpendicular to the screen and passing through the black dot displayed on each object? IA = 0.4 kg-m? Iв 3 0.5 kg-m2 Ic = 1.6 |kg•m² Ip = 1.8 kg-m?

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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