# The sound of an explosion on the surface of lake is heard by a boatman 100m away and a driver 100m below the point of explosion. (i) explain who will hear the sound of explosion first (ii) if the sound takes t s to reach the man how much time will it take to reach the driver? (speed of sound in air = 344 m/s speed of sound in water = 1533 m/s )

2
by kanwaljeetnancy

## Answers

The Brainliest Answer!
2015-02-17T11:29:23+05:30

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
For the boatman above the surface of water...

speed of sound in air = 344 m/s
distance covered = 100 m
time taken by sound = t sec
velocity = distance / time

344 = 100 / t
t  = 100 / 344
t = 0.29 sec

Now, for the man below the surface of water

speed of sound in water = 1533 m/s
distance covered = 100 m
time taken = t

But velocity = distance / time
1533 = 100 / t
t   = 100 / 1533
t  = 0.06 sec

So , the man under the water hear the sound of the explosion first....

2015-02-17T12:24:37+05:30

### This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
The word  is not  "driver", it is "diver" insider water/lake.

The time duration for sound of explosion to reach the boatman:
100 m / 344 m/s = 0.29 sec

The time duration for the sound of explosion to reach the diver traveling through water in the lake =  100 m / 1533 m/s = 0.065 sec

Since the speed of sound in water in the lake is more than the speed of sound in air, the sound will reach the diver first.