A thin disk rotates about an axis that goes through its center perpendicular to its plane. The disk is rotating counter- clockwise and slowing down. What can be said about the angular speed and acceleration of the disk? O Angular speed is positive, angular acceleration is positive O Angular speed is negative, angular acceleration is positive O Angular speed is negative, angular acceleration is negative O Angular speed is positive, angular acceleration is negative

A thin disk rotates about an axis that goes through its center perpendicular to its plane. The disk is rotating counter- clockwise and slowing down. What can be said about the angular speed and acceleration of the disk? O Angular speed is positive, angular acceleration is positive O Angular speed is negative, angular acceleration is positive O Angular speed is negative, angular acceleration is negative O Angular speed is positive, angular acceleration is negative

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 49P: A wind turbine is rotating conterclockwise at 0.5 rev/s and slows to a stop in 10 s. Its blades are...

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A bicycle tire is spinning clockwise at 2.50 rad/s. During a time period t = 1.25 s, the tire is slopped and spun in the opposite (counterclockwise) direction, also at 2.50 rad/s. (Calculate (a) the change in the tires angular velocity and (b) the tire's average angular acceleration av.
A bug of mass 0.020 kg is at rest on the edge of a solid cylindrical disk (M=0.10kg,R=0.10m) rotating in a horizontal plane around the vertical axis through its center. The disk is rotating at 10.0 rad/s. The bug crawls to the center of the disk. (a) What is the new angular velocity of the disk? (b) What is the change in the kinetic energy of the system? (c) If the bug crawls back to the outer edge of the disk, what is the angular velocity of the disk then? (d) What is the new kinetic energy of the system? (e) What is the cause of the increase and decrease of kinetic energy?
Integrated Concepts An ultracentrifuge accelerates from rest to 100,000 rpm in 2.00 min. (a) What is its angular acceleration in rad/s2? (b) What is the tangential acceleration of a point 9.50 cm from the axis of rotation? (c) What is the radial acceleration in m/s2 and multiples of g of this point at full rpm?
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