1. The disks shown in the figure have equal mass. The second disk has twice the radius of the first, but is spinning with only half the angular velocity. (a) Compare the angular momenta of the two disks: which is greater, or are they equal? (b) Compare the rotational kinetic energy of the two disks: which is greater, or are they equal? 2 2r

1. The disks shown in the figure have equal mass. The second disk has twice the radius of the first, but is spinning with only half the angular velocity. (a) Compare the angular momenta of the two disks: which is greater, or are they equal? (b) Compare the rotational kinetic energy of the two disks: which is greater, or are they equal? 2 2r

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter10: Fixed-axis Rotation

Section: Chapter Questions

Problem 57P: A baseball pitcher throws the ball in a motion where there is rotation of the forearm about the...

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A bus contains a 1500 kg flywheel (a disk that has a 0.600 m radius) and has a total mass of 10,000 kg. (a) Calculate the angular velocity the flywheel must have to contain enough energy to take the bus from rest to a speed of 20.0 m/s, assuming 90.0% of the rotational kinetic energy can be transformed into translational energy. (b) How high a hill can the bus climb with this stored energy and still have a speed of 3.00 m/s at the top of the hill? Explicitly show how you follow the steps in the Problem-Solving Strategy for Rotational Energy.
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