PADI Divemaster Certification Practice Exam

How much faster does sound travel in water compared to air?

1. 2 times faster

2. 3 times faster

3. 4 times faster

4. 5 times faster

The correct answer is: 4 times faster

Sound travels significantly faster in water than in air due to the differences in the medium's density and molecular structure. In general, sound waves travel through vibrations in particles, and since water molecules are much closer together than the molecules in air, sound waves can transmit their energy more efficiently. The speed of sound in air is approximately 343 meters per second at sea level and at a temperature of 20 degrees Celsius, while in water, sound travels at about 1,480 meters per second. When you compare these two speeds, the speed of sound in water is roughly four times that in air. Hence, the correct choice reflects this ratio, confirming that sound travels about four times faster in water, which is vital information for divers as it affects communication and the perception of sounds underwater. Understanding this concept can also have implications in marine biology, underwater acoustics, and various diving situations.