Rotational Dynamics: In a laboratory experiment, a student brings up the rotational speed of a flywheel to 30.0 rpm. She then allows it to slow down on its own, and counts 240 revolutions before the apparatus uniformly comes to a stop. The moment of inertia of the flywheel is 0.0850 kg ? m2. What is the magnitude of the retarding torque on the flywheel?
A. 0.0425 N ? m
B. 0.159 N ? m
C. 0.0787 N ? m
D. 0.000278 N ? m
E. 0.0000136 N ? m
Answer: D
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a) exactly 101 megahertz b) less than 101 megahertz c) greater than 101 megahertz