1. From lihe sop of a tower of height 40 m, e ball is projected up war

1.	1. From lihe sop of a tower of height 40 m, e ball is projected up wards with a speed of 20 rmsat an angle of elevation of30 Then the ratio of the total time taken by the ball to hit the ground to the fime taken to hall come af sarme level autop of towerA)2:1B) 3:1C) 3:2D) 4 I
Answer» 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

1. From lihe sop of a tower of height 40 m, e ball is projected up wards with a speed of 20 rmsat an angle of elevation of30 Then the ratio of the total time taken by the ball to hit the ground to the fime taken to hall come af sarme level autop of towerA)2:1B) 3:1C) 3:2D) 4 I

Answer»

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

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1. From lihe sop of a tower of height 40 m, e ball is projected up wards with a speed of 20 rmsat an angle of elevation of30 Then the ratio of the total time taken by the ball to hit the ground to the fime taken to hall come af sarme level autop of towerA)2:1B) 3:1C) 3:2D) 4 I

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