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A string is wrapped around the rim of a wheel of moment of inertia 0.40 kgm2 and radius 10 cm. The wheel is free to rotate about its axis. Initially the wheel is at rest. The string is now pulled by a force of 40 N. The angular velocity of the wheel after 10 s is x rad/s, where x is .
100
Torque = FR = 40 0.1 = 4 N m
= I = 40.40 = 10 rad s-2
Starting from rest, = t = 10 10 = 100 rad/s
Answer: 100
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