Q.20. A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.
Given the distance of the object is 3625 m from the submarine and the time taken is 5 seconds.
But the time gave includes of both journey downward and upward,
hence the time taken will be half of this time.
Putting the values in the equation, we get
Therefore, the speed of sound is 1450 m/s.