A motor drives a disk initially at rest through 23.9 rotations in 5.0 s. Assume the vector sum of the torques caused by the force exerted by the motor and the force of friction is constant. The rotational inertia of the disk is 4.0 kgm². When the motor is switched off, the disk comes to rest in 12 s. (a) What is the torque created by the force of friction? (b) What is the torque caused by the force exerted by the motor?

A motor drives a disk initially at rest through 23.9 rotations in 5.0 s. Assume the vector sum of the torques caused by the force exerted by the motor and the force of friction is constant. The rotational inertia of the disk is 4.0 kgm². When the motor is switched off, the disk comes to rest in 12 s. (a) What is the torque created by the force of friction? (b) What is the torque caused by the force exerted by the motor?

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 49PQ: A turntable (disk) of radius r = 26.0 cm and rotational inertia0.400 kg m2 rotates with an angular...

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