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CBSE Class 9 Answered

.THE SOUND OF A EXPLOSION ON THE SURFACE OF LAKE IS HEARD BY A BOATMAN 100m AWAY AND A DIVER 100m BELOW THE POINT OF EXPLOSION. i)who will hear sound first boatman or diver? why?
Asked by | 05 Mar, 2013, 12:01: PM
answered-by-expert Expert Answer
time to reach the sound to the boatman=t1=100/340=0.29s
time to reach the sound to the diver=t2=100/v where v is speed of sound in lake water.
as vin lake will be always be greater than the speed of sound in air.
so t2<t1
so the boat man will hear the sound first.
Answered by | 05 Mar, 2013, 04:09: PM

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