Physics of Everyday Phenomena
9th Edition
ISBN: 9781259894008
Author: W. Thomas Griffith, Juliet Brosing Professor
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 8, Problem 18E
A student, sitting on a stool holds masses in each hand. When his arms are extended, the total rotational inertia of the system is 5.6 kg·m2. When he pulls his arms in close to his body, he reduces the total rotational inertia to 1.4 kg·m2. When he is rotating with his hands held close to his body, his rotational velocity is 48 RPM. If there are no external torques, what is the rotational velocity of the system when he extends his arms?
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Physics of Everyday Phenomena
Ch. 8 - Which units would not be appropriate for...Ch. 8 - Which units would not be appropriate for...Ch. 8 - A coin rolls down an inclined plane, gaining speed...Ch. 8 - The rate of rotation of an object is gradually...Ch. 8 - Is the rotational velocity of a child sitting near...Ch. 8 - Is the linear speed of a child sitting near the...Ch. 8 - If an object has a constant rotational...Ch. 8 - A ball rolls down an inclined plane, gaining speed...Ch. 8 - Which, if either, will produce the greater torque:...Ch. 8 - Which of the forces pictured as acting upon the...
Ch. 8 - The two forces in the diagram have the same...Ch. 8 - Is it possible to balance two objects of different...Ch. 8 - Is it possible for the net force acting on an...Ch. 8 - You are trying to move a large rock using a steel...Ch. 8 - Prob. 15CQCh. 8 - Prob. 16CQCh. 8 - Prob. 17CQCh. 8 - An object is rotating with a constant rotational...Ch. 8 - A tall crate has a higher center of gravity than a...Ch. 8 - Two objects have the same total mass, but object A...Ch. 8 - Is it possible for two objects with the same mass...Ch. 8 - Can you change your rotational inertia about a...Ch. 8 - A solid sphere and a hollow sphere made from...Ch. 8 - Is angular momentum always conserved? Explain.Ch. 8 - A metal rod is rotated first about an axis through...Ch. 8 - A child on a freely rotating merry-go-round moves...Ch. 8 - Moving straight inward, a large child jumps onto a...Ch. 8 - Is it possible for an ice skater to change his...Ch. 8 - Suppose you are rotating a ball attached to a...Ch. 8 - Does the direction of the angular-momentum vector...Ch. 8 - Does the direction of the angular momentum vector...Ch. 8 - Can a yo-yo be made to sleep if the string is tied...Ch. 8 - An ice skater is spinning counterclockwise about a...Ch. 8 - A pencil, balanced vertically on its eraser, falls...Ch. 8 - A top falls over quickly if it is not spinning,...Ch. 8 - When we shift gears on the rear-wheel gear of a...Ch. 8 - In what foot position do we exert maximum torque...Ch. 8 - If we move the chain to a larger sprocket on the...Ch. 8 - Suppose a merry-go-round is rotating at the rate...Ch. 8 - When one of the authors was a teenager, the rate...Ch. 8 - Suppose a disk rotates through eight revolutions...Ch. 8 - The rotational velocity of a merry-go-round...Ch. 8 - A bicycle wheel is rotationally accelerated at the...Ch. 8 - The rotational velocity of a spinning disk...Ch. 8 - Starting from rest, a merry-go-round accelerates...Ch. 8 - A force of 60 N is applied at the end of a wrench...Ch. 8 - A weight of 40 N is located a distance of 8 cm...Ch. 8 - A weight of 8 N is located 12 cm from the fulcrum...Ch. 8 - Two forces are applied to a merry-go-round with a...Ch. 8 - A net torque of 93.5 Nm is applied to a disk with...Ch. 8 - A wheel with a rotational inertia of 8.3 kgm2...Ch. 8 - A torque of 76 Nm producing a counterclockwise...Ch. 8 - Two 0.3-kg masses are located at either end of a...Ch. 8 - A mass of 0.75 kg is located at the end of a very...Ch. 8 - A uniform disk with a mass of 7 kg and a radius of...Ch. 8 - A student, sitting on a stool holds masses in each...Ch. 8 - A merry-go-round in the park has a radius of 1.5 m...Ch. 8 - Prob. 2SPCh. 8 - In the park, several children (having a total mass...Ch. 8 - A student sitting on a stool that is free to...
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