A playground ride consists of a disk of mass M = 38 kg and radius R = 1.5 m mounted on a low-friction axle (see figure below). A child of mass m = 24 kg runs at speed v = 2.5 m/s on a line tangential to the disk and jumps onto the outer edge of the disk. R m M

A playground ride consists of a disk of mass M = 38 kg and radius R = 1.5 m mounted on a low-friction axle (see figure below). A child of mass m = 24 kg runs at speed v = 2.5 m/s on a line tangential to the disk and jumps onto the outer edge of the disk. R m M

Name: Part 5(f) What is the change in the kinetic energy of the child plus
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Description: Part 5(f) What is the change in the kinetic energy of the child plus the disk, from the beginning to the end of the walk on the disk?iJSave for LaterAttempts: 0 of 4 usedSubmit Answer A playground ride consists of a disk of mass M = 38 kg and radius

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter13: Rotation Ii: A Conservation Approach

Section: Chapter Questions

Problem 30PQ

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A massless spring of constant k = 78.4 N/m is fixed on the left side of a level track. A block of mass m = 0.50 kg is pressed against the spring and compresses it a distance d, as in Figure P7.74. The block (initially at rest) is then released and travels toward a circular loop-the-loop of radius R = 1.5 m. The entire track and the loop-the-loop are frictionless, except for the section of track between points A and B. Given that the coefficient of kinetic friction between the block and the track along AB is k = 0.30 and that the length of AB is 2.5 m, determine the minimum compression d of the spring that enables the block to just make it through the loop-the-loop at point C. Hint: The force exerted by the track on the block will be zero if the block barely makes it through the loop-the-loop. Figure P7.74
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A massless spring of constant k = 78.4 N/m is fixed on the left side of a level track. A block of mass m = 0.50 kg is pressed against the spring and compresses it a distance d, as in Figure P7.74. The block (initially at rest) is then released and travels toward a circular loop-the-loop of radius R = 1.5 m. The entire track and the loop-the-loop are frictionless, except for the section of track between points A and B. Given that the coefficient of kinetic friction between the block and the track along AB is k = 0.30 and that the length of AB is 2.5 m, determine the minimum compression d of the spring that enables the block to just make it through the loop-the-loop at point C. Hint: The force exerted by the track on the block will be zero if the block barely makes it through the loop-the-loop. Figure P7.74
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