The length of a seconds pendulum is .... $cm$.

$A$ person of mass $M$ is sitting on a swing of length $L$ and swinging with an angular amplitude $\theta_0$. If the person stands up when the swing passes through its lowest point,the work done by him,assuming that his centre of mass moves by a distance $l$ $(l << L)$,is close to

$A$ pendulum has a time period $T$ in air. When it is made to oscillate in water, its time period is $\sqrt{2} T$. Then the relative density of the material of the bob of the pendulum is (neglect damping).

The time period of a simple pendulum on a freely moving artificial satellite is

$A$ simple pendulum is suspended in a car. The car starts moving on a horizontal road according to the equation $x = \frac{g}{2} \sqrt{3} t^2$. Find the time period of oscillation of the pendulum.

$A$ pendulum is hung from the roof of a sufficiently high building and is moving freely to and fro like a simple harmonic oscillator. The acceleration of the bob of the pendulum is $20 \; m/s^2$ at a distance of $5 \; m$ from the mean position. The time period of oscillation is