A long uniform rod of length L and mass M is pivoted vertically on a horizontal, friction less pivot at its lower end. The rod is released from rest in its vertical position OA (see figure). It falls off without slipping at O. At the instant the rod is horizontal,

A

Its angular speed is $$\sqrt{\frac{3g}{L}}$$

B

Magnitude of its angular acceleration is $$\frac{3g}{2L}$$

C

Acceleration of its centre of mass is $$\vec{a}_{CM} = -\frac{3g}{4}\hat{j}$$

D

Reaction force at pivot $$= \frac{Mg}{4}\hat{j}$$