#### A body is thrown vertically upward with velocity u, the greatest height h to which it will rise is,(a) $\frac{u}{g}$(b) $\frac{u^{2}}{2g}$(c) $\frac{u^{2}}{g}$(d) $\frac{u}{2g}$

Ans. B

Sol.

The body is thrown upwards with some initial velocity and acceleration due to gravity is constant, which will retard the body.

As the acceleration is constant we can use equation of motion.

By using third equation of motion and putting proper values as-

$v^{2}=u^{2}+2as$

where v = 0 and a= -g

$0^{2}=u^{2}+2(-g)h$

$h=\frac{u^{2}}{2g}$

Hence, the correct answer is option B