$A$ man in a balloon rising vertically with an acceleration of $4.9 \, m/s^2$ releases a ball $2 \, s$ after the balloon is let go from the ground. The greatest height above the ground reached by the ball is .......... $m$ :-

The vertical height of point $P$ above the ground is twice that of $Q$. $A$ particle is projected downward with a speed of $5 \, m/s$ from $P$ and at the same time another particle is projected upward with the same speed from $Q$. Both particles reach the ground simultaneously,then:

$A$ body is falling freely from a point $A$ at a certain height from the ground and passes through points $B, C$, and $D$ (vertically as shown below) such that $BC = CD$. The time taken by the particle to move from $B$ to $C$ is $2 \ s$ and from $C$ to $D$ is $1 \ s$. The time taken to move from $A$ to $B$ in seconds is

$A$ packet is dropped from a balloon which is going upwards with a velocity of $12 \, m/s$. The velocity of the packet after $2 \, s$ will be ........ $m/s$.

$A$ body is projected vertically upwards at time $t=0$ and it is seen at a height $H$ at times $t_1$ and $t_2$ seconds during its flight. The maximum height attained is ($g$ is acceleration due to gravity).

$A$ body is released from the top of a tower $H$ metre high. It takes $t$ seconds to reach the ground. The height of the body $\frac{t}{2}$ seconds after release is