Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
4th Edition
ISBN: 9780133942651
Author: Randall D. Knight (Professor Emeritus)
Publisher: PEARSON
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Chapter 12, Problem 80EAP
Luc, who is 1.80 m tall and weighs 950 N, is standing at the center of a playground merry-go-round with his arms extended, holding a 4.0 kg dumbbell in each hand. The merry-go-round can be modeled as a 4.0-m-diameter disk with a weight of 1500 N. Luc’s body can be modeled as a uniform 40-cm-diameter cylinder with massless arms extending to hands that are 85 cm from his center. The merry-go-round is coasting at a steady 35 rpm when Luc brings his hands in to his chest. Afterward, what is the
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Luc, who is 1.80 m tall and weighs 950 N, is standing at the center of a playground merry-go-round with his arms extended, holding a 4.0 kg dumbbell in each hand. The merry-go-round can be modeled as a 4.0-m-diameter disk with a weight of 1500 N. Luc's body can be modeled as a uniform 40-cm-diameter cylinder with massless arms extending to hands that are 85 cm from his center. The merry-go-round is coasting at a steady 35 rpm when Luc brings his hands in to his chest.
Afterward, what is the angular velocity, in rpm, of the merry-go-round?
A merry-go-round is a common piece of playground equipment. A 3.0-m-diameter merry-go-round, which can be modeled as a disk with a mass of 210 kg , is spinning at 17 rpm. John runs tangent to the merry-go-round at 5.2 m/s, in the same direction that it is turning, and jumps onto the outer edge. John's mass is 30 kg.
What is the merry-go-round's angular velocity, in rpm, after John jumps on?
A 45 kg figure skater is spinning on the toes of her skates at
0.60 rev/s. Her arms are outstretched as far as they will go. In
this orientation, the skater can be modeled as a cylindrical torso
(40 kg, 20 cm average diameter, 160 cm tall) plus two rod-like
arms (2.5 kg each, 61 cm long) attached to the outside of the
torso. The skater then raises her arms straight above her head,
where she appears to be a 45 kg, 20-cm-diameter, 200-cm-tall
cylinder.
Part A
What is her new rotation frequency, in revolutions per second?
Express your answer in revolutions per second to two significant figures.
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Chapter 12 Solutions
Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
Ch. 12 - Prob. 1CQCh. 12 - If the angular velocity w is held constant, by...Ch. 12 - FIGURE Q12.3 shows three rotating disks, all of...Ch. 12 - 4. Must an object be rotating to have a moment of...Ch. 12 - 5. The moment of inertia of a uniform rod about an...Ch. 12 - 6. You have two solid steel spheres. Sphere 2 has...Ch. 12 - The professor hands you two spheres. They have the...Ch. 12 - Six forces are applied to the door in FIGURE...Ch. 12 - Prob. 9CQCh. 12 - Rank in order, from largest to smallest, the...
Ch. 12 - The solid cylinder and cylindrical shell in FIGURE...Ch. 12 - A diver in the pike position (legs straight, hands...Ch. 12 - Prob. 13CQCh. 12 - A high-speed drill reaches 2000 rpm in 0.50 s. a....Ch. 12 - A skater holds her arms outstretched as she spins...Ch. 12 - A ceiling fan with 80-cm-diameter blades is...Ch. 12 - An 18-cm-long bicycle crank arm, with a pedal at...Ch. 12 - Prob. 5EAPCh. 12 - The three masses shown in FIGURE EX12.6 are...Ch. 12 - The three masses shown in FIGURE EX12.7 are...Ch. 12 - A 100 g ball and a 200 g ball are connected by a...Ch. 12 - A thin, 100 g disk with a diameter of 8.0 cm...Ch. 12 - What is the rotational kinetic energy of the...Ch. 12 - The three200g masses in FIGURE EX12.11 are...Ch. 12 - A drum major twirls a 96-cm-long, 400 g baton...Ch. 12 - The four masses shown in FIGURE EX12.13 are...Ch. 12 - The four masses shown in FIGURE EXI2.13 are...Ch. 12 - The three masses shown in FIGURE EXI2.15 are...Ch. 12 - A 12-cm-diameter CD has a mass of 21 g. What is...Ch. 12 - A 25 kg solid door is 220 cm tall, 91 cm wide....Ch. 12 - Prob. 18EAPCh. 12 - In FIGURE EX12.19, what magnitude force provides...Ch. 12 - The 20-cm-diameter disk in FIGURE EX12.20 can...Ch. 12 - The axle in FIGURE EXI2.21 is half the distance...Ch. 12 - A 4.0-rn-long, 500 kg steel beam extends...Ch. 12 - An athlete at the gym holds a 3.0 kg steel ball in...Ch. 12 - An object’s moment of inertia is 2.0 kg m2. Its...Ch. 12 - An object whose moment of inertia is 4.0 kg m2...Ch. 12 - A 1.0 kg ball and a 2.0 kg ball are connected by a...Ch. 12 - Starting from rest, a 12-cm-diameter compact disk...Ch. 12 - A 4.0 kg, 36-cm-diameter metal disk, initially at...Ch. 12 - The two objects in FIGURE EXI2.29 are balanced on...Ch. 12 - Prob. 30EAPCh. 12 - The 3.0-rn-long, 100 kg rigid beam of FIGURE...Ch. 12 - A 5.0 kg cat and a 2.0 kg bowl of tuna fish are at...Ch. 12 - A car tire is 60cm in diameter. The car is...Ch. 12 - A 500 g, 8.0-cm-diameter can is filled with...Ch. 12 - Prob. 35EAPCh. 12 - A solid sphere of radius R is placed at a height...Ch. 12 - Prob. 37EAPCh. 12 - Evaluate the cross products AB and CD .Ch. 12 - Prob. 39EAPCh. 12 - Force F=10j N is exerted on a particle at 5i+5j m....Ch. 12 - A 1.3 kg ball on the end of a lightweight rod is...Ch. 12 - What are the magnitude and direction of the...Ch. 12 - What is the angular momentum vector of the 2.0 kg,...Ch. 12 - Prob. 44EAPCh. 12 - Prob. 45EAPCh. 12 - A 2.0 kg, 20-cm-diameter turntable rotates at 100...Ch. 12 - Prob. 47EAPCh. 12 - A toy gyroscope has a ring of mass M and radius R...Ch. 12 - Prob. 49EAPCh. 12 - Prob. 50EAPCh. 12 - Determine the moment of inertia about the axis of...Ch. 12 - What is the moment of inertia of a 2.0 kg,...Ch. 12 - Calculate by direct integration the moment of...Ch. 12 - Calculate the moment of inertia of the rectangular...Ch. 12 - a. A disk of mass M and radius R has a hole of...Ch. 12 - Consider a solid cone of radius R, height H, and...Ch. 12 - Prob. 57EAPCh. 12 - A 3.0-m-long ladder, as shown in Figure 12.35....Ch. 12 - In FIGURE P12.59, an 80 kg construction worker...Ch. 12 - Prob. 60EAPCh. 12 - Prob. 61EAPCh. 12 - A 120-cm-wide sign hangs from a 5.0 kg,...Ch. 12 - Prob. 63EAPCh. 12 - Flywheels are large, massive wheels used to store...Ch. 12 - of mass m1and m2are connected by a massless string...Ch. 12 - The 2.0 kg, 30-cm-diameter disk in FIGURE P12.66...Ch. 12 - A 30-cm-diameter, 1.2 kg solid turntable rotates...Ch. 12 - Your engineering team has been assigned the task...Ch. 12 - A hollow sphere is rolling along a horizontal...Ch. 12 - A 750 g disk and a 760 g ring, both 15 cm in...Ch. 12 - A cylinder of radius R, length L. and mass M is...Ch. 12 - The 5.0 kg, 60-cm-diameter disk in FIGURE P12.72...Ch. 12 - A thin, uniform rod of length L and mass M is...Ch. 12 - A long, thin rod of mass M and length L is...Ch. 12 - The marble rolls down the track shown in FIGURE...Ch. 12 - sThe sphere of mass M and radius R in FIGURE...Ch. 12 - A satellite follows the elliptical orbit shown in...Ch. 12 - A 10 g bullet traveling at 400 m/s strikes a 10...Ch. 12 - A 200 g, 40-cm-diameter turntable rotates on...Ch. 12 - Luc, who is 1.80 m tall and weighs 950 N, is...Ch. 12 - A merry-go-round is a common piece of playground...Ch. 12 - A 45 kg figure skater is spinning on the toes of...Ch. 12 - Prob. 83EAPCh. 12 - The earth’s rotation axis, which is tilted 23.5...Ch. 12 - sThe bunchberry flower has the fastest-moving...Ch. 12 - The two blocks in FIGURE CP12.86 are connected by...Ch. 12 - A rod of length L and mass M has a nonuniform mass...Ch. 12 - In FIGURE CP12.88, a 200 g toy car is placed on a...Ch. 12 - Prob. 89EAPCh. 12 - A 75 g, 30-cm-long rod hangs vertically on a...
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Moment of Inertia; Author: Physics with Professor Matt Anderson;https://www.youtube.com/watch?v=ZrGhUTeIlWs;License: Standard Youtube License