Question

at an elevation angle 45" Find its time of flight and
A ball is thrown with a speed of 20 m
the horizontal range (take g = 10 ms​

Answer 1

Answer:

$t = 2 \sqrt{2} s \: range = 40m$

Explanation:

$\: given \: it \: \alpha = {45}^{0} \: u = 20 \frac{m}{s} \\ using \: the \: formula \: of \: time \: of \: flight \: t = \frac{2u \sin( \alpha ) }{g } \\ t = \frac{2 \times 20 \times \sin( {45}^{0} ) }{10} s \\ t = 4 \times \frac{1}{ \sqrt{2} } s \\ t = 2 \sqrt{ 2} s \\ using \: the \: formula \: ofhorizontal \: range \: \\ r = \frac{ {u}^{2} \sin(2 \alpha ) }{g } \\ r = \frac{20 \times 20 \times sin {90}^{0} }{10}m \\ r = 40m$

Hope it will help you.