The graph between the time period $(T)$ and the length $(l)$ of a simple pendulum is

The bob of a simple pendulum having length $l$ is displaced from the mean position to an angular position $\theta$ with respect to the vertical. If it is released,then the velocity of the bob at the lowest position is:

The bob of a pendulum of length $l$ is pulled aside from its equilibrium position through an angle $\theta$ and then released. The bob will then pass through its equilibrium position with speed $v$,where $v$ equals

The time period of a simple pendulum is $T$. When the length is increased by $10 \ cm$, its period is $T_1$. When the length is decreased by $10 \ cm$, its period is $T_2$. Then, the relation between $T, T_1$, and $T_2$ is

At a given place, to increase the number of oscillations made by a simple pendulum in one minute from $72$ to $90$, the length of the pendulum is to be decreased by (in $\%$)

Define a simple pendulum and the length of the pendulum.