Question

Stone is dropped from a tower 1000m high and on to the ground at the base of tower . When the sound of stone touching can be heard ? Speed of sound in air =344m/s

Answer 1

Answer:

17.2 sec [approx.]

Explanation:

First, let's see the time taken by the stone to reach the ground.

s=1000m/s

a=9.8m/s^2

t1=?

u=0m/s

therefore, s = 0.5at1^2 [as u=0, so ut = 0]

=> 1000 = 0.5 * 9.8 * t1^2

=> 1000 = 4.9 * t1^2

=> 204.08 = t1^2

=> t1 = 14.3 sec

now, the time taken by the sound is :

1000/344 sec

= 2.9 sec

Total time = 14.3 + 2.9 sec

= 17.2 sec. [approx.]