Question # A boy throws a ball from shoulder height at an initial velocity of ( 30 mathrm{m} / mathrm{s} ). Spending ( 4.8 mathrm{s} ) in air, the ball is caught by another boy as the same shoulder-height level. What is the angle of projection?

# A boy throws a ball from shoulder height at an initial velocity of ( 30 mathrm{m} / mathrm{s} ). Spending ( 4.8 mathrm{s} ) in air, the ball is caught by another boy as the same shoulder-height level. What is the angle of projection?

(A) ( 37^{circ} )

(B) ( 30^{circ} )

(C) ( 53^{circ} )

(D) ( 60^{circ} )

Solution

As we know

( mathrm{t}=2^{star} mathrm{u}^{star} sin @ mathrm{J} / mathrm{g} )

( 4.8=2^{*} 30^{star} sin @ / 10 )

( 4.8=6 sin @ )

( 48 / 60=sin @ )

( sin @=4 / 5 )

Hence ( @=53^{circ} )