Question

A cricket ball is throen at s dpeed 30 m/s in a direction30° above the horizental. Thr time takem bybthe ball to return the same level is​

Answer 1

Maximum height = (V sin0)² / 2g 
= (28 sin30)²/ 2 x 9.8

= 14 x 14 / 2 x 9.8
= 10m

time taken to return to the same level
=2 v sin0/ g
= 2 x 28 x sin30/ 9.8
= 2 x 28 x 1/ 2 x 9.8 
= 2.9 sec

distance from thrower to where the ball returns
= v² sin 2Ф/ g
= 28 x 28 x sin60/ 9.8 
= 69.3 m

Answer 2

Answer:

t=3 sec

Explanation:

Using formula of Projectile motion:

t=(2vi sin 30)/g

=(2*30*1/2)/10

=30/10

=3sec.....................(ANSWER