A ship sends out ultrasound that returns from the seabed and is detected after 3.42 s. If the speed of ultrasound through seawater is 1531 m/s, what is the distance of the seabed from the ship?

Solution:
Given,
Time between transmission and
detection, t = 3.42 s. Speed of ultrasound in sea water, v = 1531 m/s
Distance travelled by the ultrasound = 2 × depth of the sea = 2d
where d is the depth of the sea.
2d = speed of sound × time
= 1531 m/s × 3.42 s = 5236 m
d = 5236 m/2 = 2618 m.
Thus, the distance of the seabed from the ship is 2618 m or 2.62 km.