Question

A body is projected from the ground at an angle of 45° with the horizontal. Its velocity after $2$ $s$ is $20$ $ms^{–1}$. The maximum height reached by the body during its motion is ________ m. (use $g$ = $10$ $ms^{–2}$)

Answer 1

The maximum height reached by the body :

$⇒ v cosα = u cos\;45°$ …(i)

$v sinα = u\;sin\;45° – gt$_ _ …(ii)

$u = 20 \sqrt2$ $m/s$

$⇒ H = \frac{u^2\;sin^2\;45\degree}{20}$

$= 20 m$