Question

A cricket ball is thrown at a speed of $28m{s}^{-1}$ in a direction ${30}^0$ above the horizontal. Calculate (a) the maximum height, (b) the time taken by the ball to return to the same level and (c) the distance from the thrower to the point where the ball returns to the same level.

Answer 1

Given $u=28m/s,\theta ={30}^0$
(a) Maximum height $H=\frac{u^2{\sin }^2\theta }{2g}$
$H=\frac{{28}^2\times {0.5}^2}{2\times 9.8}=10m$

(b) Time of flight $T=\frac{2u\sin \theta }{g}$
$T=\frac{2\times 28\times \sin 30}{9.8}=2.86s$

(c) Range $R=u\cos \theta \times T$
$R=28\times \cos {30}^0\times 2.86=69.27m$