A stone is dropped into a well in which the level of water is $h$ below the top of the well. If $v$ is the velocity of sound, the time $T$ after dropping the stone at which the splash is heard is given by,

In the displacement-time graph of a moving particle shown, the instantaneous velocity of the particle is negative at the point is,

The variation of velocity of a particle moving along a straight line is shown in the figure. The distance travelled by the particle in $4 \mathrm{s}$ is,

The displacement-time graphs of two particles $A$ and $B$ are straight lines making angles of respectively $30°$ and $60°$ with the time axis. If the velocity of $A$ is $v_A$ and that of $B$ is $v_B$, then the value of $\frac{v_A}{v_B}$ is?

Starting from rest at $t=0,$ a car moves in a straight line with an acceleration given by the accompanying graph. The speed of the car at $t=3 \mathrm{s}$ is,