A uniform rod AB of length l and mass m is free to rotate about point A . The rod is released from rest in the horizontal position. The initial angular acceleration of the rod will be

Step-by-step solution

The moment of inertia of the uniform rod about an axis through one end and perpendicular to its length is I = ml 2 3 Where m is mass of rod and l is length. Torque τ = I α acting on centre of gravity of rod is given by τ = mg l 2 or I α = mg l 2 or ml 2 3 α = mg l 2 or α = 3 g 2 l