Question

The speed of sound in water is 1498 m/s. a sonar signal is sent straight down from a ship at a point just below the water surface, and 1.80 s later the reflected signal is detected. how deep is the ocean beneath the ship?

Answer 1

The 1.8 s is the time for the signal to reach the ocean floor and return to the ship so the time to reach ocean floor = 1.8 / 2 = 0.90 seconds.
depth of ocean = speed * time

=  1498 * 0.90  =  1348.2 m  Answer