A train is moving slowly at 2   m / s next to a railway platform. A man, 1 . 5   m tall, alights from the train such that his feet are fixed on the ground. Taking him to be a rigid body, the instantaneous angular velocity (in rad / s ) is

Step-by-step solution

As man alight, its angular momentum about a point on platform is conserved. By angular momentum conservation, L initial = L final ⇒ m v r = I ω ⇒ m v r = m l 2 3 · ω ⇒ 3 v r l 2 = ω or ω = 3 × 2 × 1 . 5 2 1 . 5 2 = 2 rad / s So, instantaneous angular speed of man = 2 rad / s .