Question

From the top of a tower of height 40m a ball is projected upwards with a speed of 20m/s

Answer 1

Explanation:

Time taken to reach maximum height in a horizontal projection :

H = 20²sin²30° / 2 × 10

H = (400 × 0.25) / 20 = 5m

Total height is :

5 + 40 = 45 m

Time of flight = (2 × 20 × Sin 30) / 10 = 2 seconds

Time of free fall is √(2 × 45)/10 = √9 = 3 seconds.

The total time taken to reach the ground is thus :

1 + 3 = 4 Seconds

The ratio is thus :

4 : 2