4. Two identical disks (same mass and radius) have a common axis. Initially one of the disks is spinning with a constant angular velocity. When the two disks are brought into contact, they stick together. Which of the following statements is true? (a) The total kinetic energy and the total angular momentum are unchanged from their initial values. (b) Both the total kinetic energy and the total angular momentum are reduced to half of their original values. (c) The total angular momentum is unchanged, but the total kinetic energy is reduced to half its original value. (d) The total angular momentum is reduced to one-half of its original value, but the total kinetic energy is unchanged. (e) The total angular momentum is unchanged, but the total kinetic energy is reduced to one-quarter of its original value.

4. Two identical disks (same mass and radius) have a common axis. Initially one of the disks is spinning with a constant angular velocity. When the two disks are brought into contact, they stick together. Which of the following statements is true? (a) The total kinetic energy and the total angular momentum are unchanged from their initial values. (b) Both the total kinetic energy and the total angular momentum are reduced to half of their original values. (c) The total angular momentum is unchanged, but the total kinetic energy is reduced to half its original value. (d) The total angular momentum is reduced to one-half of its original value, but the total kinetic energy is unchanged. (e) The total angular momentum is unchanged, but the total kinetic energy is reduced to one-quarter of its original value.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 68P: Two astronauts (Fig. P10.67), each having a mass M, are connected by a rope of length d having...

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