Question

From the top of a tower of height 50m A ball is projected upwards with a speed of 30 metre per second at an angle of 30 degree to the horizontal then calculate:
i) maximum height from the ground ii)At what distance from the foot of the tower does the projected hit the ground iii)time of flight

Answer 1

Answer:

93.75 m

6.83 sec

295.7 m

Explanation:

From the top of a tower of height 50m A ball is projected upwards with a speed of 30 metre per second at an angle of 30 degree to the horizontal

Horizontal Velocity = 50Cos30 = 25√3 m/s

Vertical Velocity = 50Sin30 = 25 m/s

Time to reach at peak using V = u + at

Vertical Velocity at top = 0 , a = -g = -10 m/²

=> 0 = 25 +(-10)t

=> t = 2.5 sec

Vertical Distance using S = ut + (1/2)at²

= 30*2.5 +(1/2)(-10)2.5²

= 43.75 m

Max height from ground = 50 + 43.75 = 93.75 m

Time to reach at ground

93.75 = (1/2)10*t²

=> t = 4.33 Sec

Time of Flight = 2.5 + 4.33 = 6.83 sec

Horizontal Distance = 25√3  * 6.83 = 295.7 m