$A$ stone falls freely such that the distance covered by it in the last second of its motion is equal to the distance covered by it in the first $5 \,s$. It is in air for....... $s$.

An object is thrown vertically upwards. At its maximum height,which of the following quantities becomes zero?

$A$ ball is thrown vertically upwards with a velocity of $20 \; m s^{-1}$ from the top of a multistorey building. The height of the point from where the ball is thrown is $25.0 \; m$ from the ground. How high will the ball rise above the point of projection (in $; m$)? Take $g = 10 \; m s^{-2}$.

$A$ boy throws balls into the air at a regular interval of $2 \, s$. The next ball is thrown when the velocity of the first ball is zero. How high does the ball rise above his hand (in $, m$)? [Take $g = 9.8 \, m/s^2$]

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

From the top of a $64\, ft$ high tower,a stone is thrown upwards vertically with the velocity of $48\, ft/s$. The greatest height (in $ft$) attained by the stone,assuming the value of the gravitational acceleration $g = 32\, ft/s^2$,is