Question

A stone is thrown in a vertically upward direction with a velocity of $5m{s}^{-1}$ . If the acceleration of the stone during its motion is $10m{s}^{-2}$ in the downward direction, what will be the height attained by the stone and how much time will it take to reach there?

Answer 1

Given,

$Velocity=5m/s,a=10m/s^2$

So, the height is:

$v^2-u^2=2as$

$s=\frac{v^2-u^2}{2a}$

$=\frac{0-25}{2\times (-10)}=1.25$ since $v=0$

Since $a$ is negative so its direction is opposite to the direction of motion.

So,

$t=\frac{v-u}{a}=\frac{0-5}{-10}=\frac{1}{2}$

$time=0.5s$