A pendulum of length 2 m consists of a wooden bob of mass 50 g. A bullet of mass 75 g is fired towards the stationary bob with a speed v. The bullet emerges out of the bob with a speed $\frac{v}{3}$ and the bob just completes the vertical circle. The value of $\mathrm{v}$ is____ ${\mathrm{ms}}^{-1}$. (if $\mathrm{g}=10 \mathrm{m}/{\mathrm{s}}^2$ )