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lebprince
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Homework Statement
A string is wrapped around a uniform disk of mass M = 2.5 kg and radius R = 0.05 m. (Recall that the moment of inertia of a uniform disk is (1/2)MR2.) Attached to the disk are four low-mass rods of radius b = 0.09 m, each with a small mass m = 0.7 kg at the end. The device is initially at rest on a nearly frictionless surface. Then you pull the string with a constant force F = 27 N. At the instant when the center of the disk has moved a distance d = 0.038 m, a length w = 0.020 m of string has unwound off the disk.
(a) At this instant, what is the speed of the center of the apparatus?
v = m/s
(b) At this instant, what is the angular speed of the apparatus?
(c) You keep pulling with constant force 27 N for an additional 0.035 s. Now what is the angular speed of the apparatus?
I have no idea how to approach the problem. any help please