Question

Two balls are projected simultaneously with
the same speed from the top of a tower, one
vertically upwards and the other vertically
downwards. They reach the ground is 9 s and 4
s, respectively. The height of the tower is (g =
10 m/s)​

Answer 1

Answer:

180 m

Explanation:

Two balls are projected simultaneously with

the same speed from the top of a tower, one

vertically upwards and the other vertically

downwards. They reach the ground is 9 s and 4

s, respectively. The height of the tower is (g =

10 m/s)​

Let say Velocity = V

Using S = ut + (1/2)at²

Height of Tower = Distance Covered in 4 Sec = V*4 + (1/2)(10)4²

= 4V + 80

Another take time to reach ground = 9 sec

Time taken to come back at projected point = 9 - 4 = 5 sec

Time to reach peak height = 5/2 sec

Velocity at peak height = 0

=> 0 = V - 10*5/2

=> V = 25

Height of Tower = 4V + 80 = 4*25 + 80 = 180 m

Answer 2

Answer:

180m

Explanation:

t3=rt(t1 * t2)

=(rt(9* 4))

=6s

h=1/2*g*t3

h=180m