5. The motor of an engine is rotating about its axis with an angular velocity of 100 rev/minute. It comes to rest in 15 sec, after being switched off. Assuming constant angular deceleration, calculate the number of revolutions made by it before coming to rest. Ans: 12.5 revolutions. 6. A wheel of radius 10 cm can rotate freely about its centre. A string is wrapped over its rim and is pulled by a force of 5.0N. It is found that the torque produces an angular acceleration 2.0 rad/sec in the wheel. Calculate the moment of inertia of the wheel. Ans: 0.25 kg-m².