A wheel with thin spokes can be considered a hoop, where I=mr. A bicycle wheel has a mass of .35 kg with a radius of .30 m and is spinning at 25 rad/s in the positive direction. Brakes apply a force of friction of 15 N at the rim. We will consider the rim of the wheel to be on the very outside of the wheel. (Remember significant digits.) a.) What is the direction of the torque provided by the brakes (positive or negative) b.) What is the magnitude of the torque applied by the brakes? Nm c.) What is the moment of angular inertia of the wheel? kgm2 d.) What is the angular acceleration of the wheel? rad/s?

A wheel with thin spokes can be considered a hoop, where I=mr. A bicycle wheel has a mass of .35 kg with a radius of .30 m and is spinning at 25 rad/s in the positive direction. Brakes apply a force of friction of 15 N at the rim. We will consider the rim of the wheel to be on the very outside of the wheel. (Remember significant digits.) a.) What is the direction of the torque provided by the brakes (positive or negative) b.) What is the magnitude of the torque applied by the brakes? Nm c.) What is the moment of angular inertia of the wheel? kgm2 d.) What is the angular acceleration of the wheel? rad/s?

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 16PQ

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