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

From the top of a tower, a ball is thrown vertically upward which reaches the ground in $6 \,s$. A second ball thrown vertically downward from the same position with the same speed reaches the ground in $1.5\, s$. A third ball released, from the rest from the same location, will reach the ground in…….. $s$.

When a ball is thrown up vertically with velocity ${V_o}$, it reaches a maximum height of '$h$'. If one wishes to triple the maximum height then the ball should be thrown with velocity

A ball $P$ is dropped vertically and another ball Q is thrown horizontally with the same velocities from the same height and at the same time. If air resistance is neglected, then

A stone is dropped from the top of a building. When it crosses a point $5\, m$ below the top, another stone starts to fall from a point $25\, m$ below the top. Both stones reach the bottom of building simultaneously. The height of the building is ….. $m$.