The value of W = 1.8 lb and L = 3 ft A L 9. Determine the angular velocity-(rad/s) as it passes through a vertical position. a.) 5.148 b.) 5.674 c.) 4.721 d.) 4.485 10. Determine the corresponding reaction in lbs at the pivot. a.) 5.40 b.) 6.30 c.) 4.50 d.) 6.7 B 9. 11. A 200-kg flywheel is at rest when a constant 300 N-m couple is applied. After executing 560 revolutions, the flywheel reaches its rated speed of 2400 rpm. Knowing that the radius of gyration of the flywheel is 0.4m, determine the average magnitude of the couple due to kinetic friction in the bearing. a.) 14.240 b.) 12.768 c.) 11.824 d.) 13.721 12. The rotor of an electric motor has an angular velocity of 3600 rpm when the load and power are cut off. The 110-lb rotor, which has a centroidal radius of gyration of 9 in., then coasts to rest. Knowing that the kinetic friction of the rotor produces a couple with a magnitude of 2.5 lb-ft, determine the number of revolutions that the rotor executes before coming to rest. a.) 8.693 b.) 9.365 c.) 11.024 d.) 12.351

The value of W = 1.8 lb and L = 3 ft A L 9. Determine the angular velocity-(rad/s) as it passes through a vertical position. a.) 5.148 b.) 5.674 c.) 4.721 d.) 4.485 10. Determine the corresponding reaction in lbs at the pivot. a.) 5.40 b.) 6.30 c.) 4.50 d.) 6.7 B 9. 11. A 200-kg flywheel is at rest when a constant 300 N-m couple is applied. After executing 560 revolutions, the flywheel reaches its rated speed of 2400 rpm. Knowing that the radius of gyration of the flywheel is 0.4m, determine the average magnitude of the couple due to kinetic friction in the bearing. a.) 14.240 b.) 12.768 c.) 11.824 d.) 13.721 12. The rotor of an electric motor has an angular velocity of 3600 rpm when the load and power are cut off. The 110-lb rotor, which has a centroidal radius of gyration of 9 in., then coasts to rest. Knowing that the kinetic friction of the rotor produces a couple with a magnitude of 2.5 lb-ft, determine the number of revolutions that the rotor executes before coming to rest. a.) 8.693 b.) 9.365 c.) 11.024 d.) 12.351

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter8: Rotational Equilibrium And Dynamics

Section: Chapter Questions

Problem 73P: A cylinder with moment of inertia I1 rotates with angular velocity 0 about a frictionless vertical...

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