University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Chapter 9, Problem 9.72P
A physics student of mass 43.0 kg is standing at the edge of the flat roof of a building, 12.0 m above the sidewalk. An unfriendly dog is running across the roof toward her. Next to her is a large wheel mounted on a horizontal axle at its center. The wheel, used to lift objects from the ground to the roof, has a light crank attached to it and a light rope wrapped around it; the free end of the rope hangs over the edge of the roof. The student grabs the end of the rope and steps off the roof. If the wheel has radius 0.300 m and a moment of inertia of 9.60 kg · m2 for rotation about the axle, how long does it take her to reach the sidewalk, and how- fast will she be moving just before she lands? Ignore friction.
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Chapter 9 Solutions
University Physics (14th Edition)
Ch. 9 - Which of the following formulas is valid if the...Ch. 9 - A diatomic molecule can be modeled as two point...Ch. 9 - What is the difference between tangential and...Ch. 9 - In Fig. Q9.4, all points on the chain have the...Ch. 9 - In Fig. Q9.4, how are the radial accelerations of...Ch. 9 - A flywheel rotates with constant angular velocity....Ch. 9 - What is the purpose of the spin cycle of a washing...Ch. 9 - You are designing a flywheel to store kinetic...Ch. 9 - Can you think of a body that has the same moment...Ch. 9 - To maximize the moment of inertia of a flywheel...
Ch. 9 - How might you determine experimentally the moment...Ch. 9 - A cylindrical body has mass M and radius R. Can...Ch. 9 - Describe how you could use part (b) of Table 9.2...Ch. 9 - A hollow spherical shell of radius R that is...Ch. 9 - For the equations for I given in parts (a) and (b)...Ch. 9 - In part (d) of Table 9.2, the thickness of the...Ch. 9 - Two identical balls, A and B, are each attached to...Ch. 9 - An elaborate pulley consists of four identical...Ch. 9 - You can use any angular measureradians, degrees,...Ch. 9 - When calculating the moment of inertia of an...Ch. 9 - A wheel is rotating about an axis perpendicular to...Ch. 9 - Estimate your own moment of inertia about a...Ch. 9 - (a) What angle in radians is subtended by an are...Ch. 9 - An airplane propeller is rotating at 1900 rpm...Ch. 9 - CP CALC The angular velocity of a flywheel obeys...Ch. 9 - CALC A fan blade rotates with angular velocity...Ch. 9 - CALC A child is pushing a merry-go-round. 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According to the shop manual, when...Ch. 9 - Four small spheres, each of which you can regard...Ch. 9 - Calculate the moment of inertia of each of the...Ch. 9 - Calculate the moment of inertia of each of the...Ch. 9 - A uniform bar has two small balls glued to its...Ch. 9 - You are a project manager for a manufacturing...Ch. 9 - A wagon wheel is constructed as shown in Fig....Ch. 9 - An airplane propeller is 2.08 m in length (from...Ch. 9 - A compound disk of outside diameter 140.0 cm is...Ch. 9 - A wheel is turning about an axis through its...Ch. 9 - A uniform sphere with mass 28.0 kg and radius...Ch. 9 - A hollow spherical shell has mass 8.20 kg and...Ch. 9 - The flywheel of a gasoline engine is required to...Ch. 9 - You need to design an industrial turntable that is...Ch. 9 - Energy is to be stored in a 70.0-kg flywheel in...Ch. 9 - A light, flexible rope is wrapped several times...Ch. 9 - A frictionless pulley has the shape of a uniform...Ch. 9 - A bucket of mass m is tied to a massless cable...Ch. 9 - CP A thin, light wire is wrapped around the rim of...Ch. 9 - A uniform 2.00-m ladder of mass 9.00 kg is leaning...Ch. 9 - How I Scales. If we multiply all the design...Ch. 9 - Find the moment of inertia of a hoop (a...Ch. 9 - About what axis will a uniform, balsa-wood sphere...Ch. 9 - (a) For the thin rectangular plate shown in part...Ch. 9 - A thin. rectangular sheet of metal has mass M and...Ch. 9 - A thin uniform rod of mass M and length L is bent...Ch. 9 - CALC Use Eq. (9.20) to calculate the moment of...Ch. 9 - CALC Use Eq. (9.20) to calculate the moment of...Ch. 9 - CALC A slender rod with length L has a mass per...Ch. 9 - CALC A uniform disk with radius R = 0.400 m and...Ch. 9 - CP A circular saw blade with radius 0.120 m starts...Ch. 9 - CALC A roller in a printing press turns through an...Ch. 9 - CP CALC A disk of radius 25.0 cm is free to turn...Ch. 9 - You are designing a rotating metal flywheel that...Ch. 9 - You must design a device for shooting a small...Ch. 9 - Engineers are designing a system by which a...Ch. 9 - A vacuum cleaner bell is looped over a shaft of...Ch. 9 - The motor of a table saw is rotating at 3450...Ch. 9 - While riding a multispeed bicycle, the rider can...Ch. 9 - A computer disk drive is turned on starting from...Ch. 9 - It has been argued that power plants should make...Ch. 9 - A uniform disk has radius R0 and mass M0. Its...Ch. 9 - Measuring I. 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