$A$ ball is thrown vertically upwards from the ground $G$ with a speed $u$. It reaches a point $B$ at a height $h$ (lower than the maximum height) after time $t_1$. It returns to the ground after time $t_2$ from the instant it was at $B$ during the upward journey. Then $t_1t_2$ is equal to

The ratio of times taken by a freely falling body to travel the first $5 \ m$, second $5 \ m$, and third $5 \ m$ distances is:

Can a particle moving in a straight line have zero velocity and non-zero acceleration at any instant? Give an example.

$A$ balloon was moving upwards with a uniform velocity of $10 \, m/s$. An object of finite mass is dropped from the balloon when it was at a height of $75 \, m$ from the ground level. The height of the balloon from the ground when the object strikes the ground was around (in $m$). (Take the value of $g$ as $10 \, m/s^2$)

Two bodies of masses $1 kg$ and $5 kg$ are dropped gently from the top of a tower. At a point $20 cm$ from the ground,both the bodies will have the same

If the water falls from a dam into a turbine wheel $19.6 \ m$ below,then the velocity of water at the turbines is .................. $m/s$ (take $g = 9.8 \ m/s^2$).