Question

A soccer player icks a rock horizontally off a 40m high cliff into a pool f water if the player hears the sound of the splash s later, what was the inital speeed given to the rock assume the speed of sound in air to be 343?

Answer 1

v = 9.936 m/s

Step-by-step explanation:

given,

height of cliff = 40 m

speed of sound = 343 m/s

assuming that time to reach the sound to the player = 3 s

now,

time taken to fall of ball

`t = \sqrt{(2s)/(g)}`

`t = \sqrt{(2* 40)/(9.8)}`

t = 2.857 s

distance

d = v x t

d = v x 2.875

time traveled by the sound before reaching the player

`t_0 = t - t_(fall)`

`t_0 = 3 - 2.875`

`t_0 = 0.143 s`

distance traveled by the wave in this time'

r = 0.143 x 343

r= 49.05 m

now,

we know.

d² + h² = r²

d² + 40² = 49.05²

d =28.387 m

v x 2.875=28.387 m

v = 9.936 m/s