Two spheres of same size,one of mass $2\, kg$ and another of mass $4\, kg$,are dropped simultaneously from the top of Qutab Minar (height $= 72\, m$). When they are $1\, m$ above the ground,the two spheres have the same

$A$ body starts to fall freely under gravity. The distances covered by it in the first,second,and third seconds are in the ratio:

$A$ ball is dropped on the floor from a height of $10 \, m$. It rebounds to a height of $2.5 \, m$. If the ball is in contact with the floor for $0.01 \, s$,the average acceleration during contact is:

Suggest a suitable physical situation for the following $v-t$ graph.

$A$ boy is standing on top of a tower of height $85 \, m$ and throws a ball in the vertically upward direction with a certain speed. If $5.25 \, s$ later he hears the ball hitting the ground,then the speed with which the boy threw the ball is .......... $m/s$ (take $g = 10 \, m/s^2$ and speed of sound in air $= 340 \, m/s$).

$A$ $0.4\,kg$ mass takes $8\,s$ to reach the ground when dropped from a certain height $P$ above the surface of the Earth. The loss of potential energy in the last second of the fall is $..............J$. [Take $g = 10\,m/s^2$]