Question

A submarine sends out a sonar signal (sound wave) in a direction
directly downward. It takes 2.3 s for the sound wave to travel
from the submarine to the ocean bottom and back to the
submarine. How high (approx) up from the ocean floor is the
submarina? (The speed of sound in water is 1,490 m/s.)​

Answer 1

Answer:

Time of receiving of an echo     t=5 s

Distance between the object and the submarine    d=3625 m

Thus the sound wave travels a distance of  2d in 5 seconds.

Let the speed of sound in water be  v

∴    2d=v×t

2×3625=v×5              ⟹v=1450  ms−1