# A stone dropped from the top of a tower of height 300 m high splashes into the water of a pond near the base of the tower. When is the splash heard at the top given that the speed of sound in air is 340 m s–1? (g = 9.8 m s–2)

Given:

Height of the tower, h = 300 m

Initial velocity of the stone, u = 0 ms-1

Acceleration due to gravity, g = 9.8 ms-1

Speed of the sound in air = 340 ms-1

The time taken by the stone to hit the pond can be found by the second equation of motion,

s = ut + 1/2 gt2 …(1)

Where,

s = distance, in this case height

u = initial velocity

g = acceleration due to gravity

t = time

Putting the values in equation (1), we get

s = ut + 1/2 gt2

t = (2s/g)1/2

t = [2× (300m/9.8 ms-2)]1/2

t = 7.82 s

Time taken by the sound of splash to the top of the tower can also be given by,

t1 = h/v …(2)

Where,

h = height of the tower

v = velocity of sound (340 m/s)

t1 = 300m/340ms-1

t1 = 0.88 s

The total time after which splash is heard is equal to sum of the time taken by the stone to reach the water and time taken by sound to reach the tower.

i.e. T = t + t1

T = 7.82s + 0.88 s

T = 8.7 s

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Standing Wave44 mins
Sound Wave43 mins
Resonance | Master important concepts40 mins
String wave - 01 | Mastering important concepts52 mins
Energy & Power of a Wave60 mins
Doppler's Effect | Master important concepts50 mins
String wave - 02 | Mastering important concepts31 mins
Transmitted & Reflected Waves39 mins
String Wave51 mins
Sound Wave - 01 | Mastering important concepts52 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses