Two uniform solid spheres have the same mass of 2.85 kg, but one has a radius of 0.236 m while the other has a radius of 0.894 m. Each can rotate about an axis through its center. (a) What is the magnitude t of the torque required to bring the smaller sphere from rest to an angular speed of 317 rad/s in 15.5 s? N.m (b) What is the magnitude F of the force that must be applied tangentially at the sphere's equator to provide that torque? (c) What is the corresponding value of t for the larger sphere? N. m

Two uniform solid spheres have the same mass of 2.85 kg, but one has a radius of 0.236 m while the other has a radius of 0.894 m. Each can rotate about an axis through its center. (a) What is the magnitude t of the torque required to bring the smaller sphere from rest to an angular speed of 317 rad/s in 15.5 s? N.m (b) What is the magnitude F of the force that must be applied tangentially at the sphere's equator to provide that torque? (c) What is the corresponding value of t for the larger sphere? N. m

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter13: Rotation Ii: A Conservation Approach

Section: Chapter Questions

Problem 7PQ: A 12.0-kg solid sphere of radius 1.50 m is being rotated by applying a constant tangential force of...

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