If rod is displaced slightly in vertical direction, find the time period of small oscillation.
(A) $\pi \sqrt{\frac{l}{g}}$
(B) $2 \pi \sqrt{\frac{l}{g}}$
(C) $\frac{\pi}{2} \sqrt{\frac{l}{g}}$
(D) None of thesePassage 4 Figure $8.47$ shows a container having ideal liquid of variable density. The density of liquid varies as $\rho=\rho_{0}\left(4-\frac{3 h}{h_{0}}\right)$, where $h_{0}$ is height of liquid in container, $\rho_{0}$ is constant and $h$ is height from bottom. A solid block of small dimensions whose density $\frac{5}{2} \rho_{0}$ and mass $m$ is released from bottom of tank.