A boat sounds a fog horn on a day when both the sea water and the air temperature are 25.0° C. The speed of sound in sea water is 1 533 m/s. How much earlier (in s) does a dolphin 1 000 m from the source hear the sound than a person in a boat that is also 1 000 m distant? (Ignore the time it takes the sound to reach the water surface.)

Question

Quizplus · Accepted Answer

The speed of sound in air at 25°C is approximately 346 m/s. The time for sound to travel 1,000 m in water is 1000/1533 = 0.652 s. The time for sound to travel 1,000 m in air is 1000/346 = 2.89 s. The difference is 2.89 - 0.652 = 2.24 s.

A Boat Sounds a Fog Horn on a Day When