$A$ 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

What is free fall? Write the equations of uniformly accelerated motion for an object falling freely.

$A$ boy standing on a stationary lift (open from above) throws a ball upwards with the maximum initial speed he can,equal to $49\; m s^{-1}$. How much time does the ball take to return to his hands? If the lift starts moving up with a uniform speed of $5\; m s^{-1}$ and the boy again throws the ball up with the maximum speed he can,how long does the ball take to return to his hands?

$A$ student performs an experiment to determine the acceleration due to gravity $g$. The student throws a steel ball up with initial velocity $u$ and measures the height $h$ travelled by it at different times $t$. The graph the student should plot on a graph paper to readily obtain the value of $g$ is

$A$ diving board is at a height of $h$ from the water surface. $A$ swimmer standing on this board throws a stone vertically upward with a velocity of $16 \,ms^{-1}$. It reaches the water surface in a time of $5 \,s$. In the next $0.2 \,s$, the diver hears the sound from the water surface. What is the speed of sound (in $\,ms^{-1}$)? (Take acceleration due to gravity $g=10 \,ms^{-2}$)

Free-fall: Discuss the motion of an object under free fall. Neglect air resistance.