A piece of marble is projected from earth’s surface with velocity of $50ms^{- 1}$. 2 s later, it just clears a wall 5 m high. What is the angle of projection?

Question

Dr. Abubacker · Accepted Answer

(c) Horizontal component $= u\cos	heta$
Vertical component $= u\sin	heta$
$g = - 10ms^{- 2},u = 50ms^{- 1},h = 5m,t = 2\ s$
$h = u_{y}t + \frac{1}{2}gt^{2}$
[image:4_image160.emf]
$	herefore\ \ 5 = 50\sin	heta - \frac{1}{2} 	imes 10 	imes 4$
or $5 = 50\sin	heta - 20$
or $\sin	heta = \frac{25}{50} = \frac{1}{2}$
$	herefore\ 	heta = 30{^\circ}$

Q. A piece of marble is projected from earth’s surface with velocity of $50ms^{- 1}$. 2 s later, it just clears a wall 5 m high. What is the angle of projection?

Explanation

Reviewed by Dr. Abubacker

Want more practice?