The moment of inertia of the wind tunnel fan is 225 kg-m2. The fan starts from rest. The t...

The moment of inertia of the wind tunnel fan is 225 kg-m2. The fan starts from rest. The torque exerted on it by the engine is given as a function of the angular velocity of the fan by T = 140 – 0.02ω2 N-m.

(a) When the fan has turned 620 revolutions, what is its angular velocity in rpm (revolutions per minute)?

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(b) What maximum angular velocity in rpm does the fan attain?

Strategy: By writing the equation of angular motion, determine the angular acceleration of the fan in terms of its angular velocity. Then use the chain rule: