Choose the correct length $( L )$ versus square of time period $\left( T ^2\right)$ graph for a simple pendulum executing simple harmonic motion.

The period of small oscillation of a simple pendulum is $T$. The ratio of density of liquid to the density of material of the bob is $\rho \left( {\rho  < 1} \right)$.When immersed in the liquid, the time period of small oscillation will now be

What is linear harmonic oscillator ? And what is non-linear oscillator ?

If the length of the simple pendulum is increased by $44\%$, then what is the change in time period of pendulum ..... $\%$

A pendulum suspended from the ceiling of a train has a period $T$ when the train is at rest. When the train travels same distance per unit time, the period of oscillation is

A pendulum bob has a speed of $3\, {m} / {s}$ at its lowest position. The pendulum is $50 \,{cm}$ long. The speed of bob, when the length makes an angle of $60^{\circ}$ to the vertical will be $ .......\,{m} / {s}$ $\left(g=10 \,{m} / {s}^{2}\right)$