• # question_answer A bar of mass $m$ length $l$ is in pure translator motion with its centre of mass velocity $v$. It collides with and sticks to another identical bar at rest as shown in figure. Assuming that after collision it becomes one composite bar of length $2l$, the angular velocity of the composite bar will be A)  $\frac{3v}{4l}$, anti-clockwise                        B)  $\frac{4v}{3l},$anti-clockwise C)  $\frac{3v}{4l},$clockwise D)  $\frac{4v}{3l},$clockwise

By law of conservation of angular momentum $\tan \theta =\frac{r}{h/2}$ $\theta ={{45}^{o}},$        $r=\frac{h}{2}$ $\theta ={{45}^{o}}$         $n'=\frac{v}{v-{{v}_{s}}}\times n$ (anti-clockwise) Not that clockwise or anti-clockwise rotation can only be determined here by the given figure.