Question 4 (Impulse-momentum method)
Two solid spheres of radius 100 mm, each weighing 1 kg, are mounted at A and B on
the horizontal rod A'B', which rotates freely about the vertical with a counter-clockwise
angular velocity 6 rad/s. The spheres are held in position by a cord which is suddenly
cut. The centroidal moment of inertia of the rod and pivot is 0.4 kg.m². Determine:
(a) the angular velocity of the rod after the spheres have moved to positions A' and B'
[11]
(b) the energy lost due to the plastic impact of the spheres and the stops A' and B' [7].