Sound Under Water
Key Points
As you read this section, look for the information that answers this question:
How does the speed with which sound travels under water compare to the speed of sound travels through air?
The underwater world is anything but silent. You will hear yourself breathing loudly, and the snapping and clicking noises made by fish and other marine life. You will also hear engines of boats overhead.
- Because water is about 800 times denser than air, it conducts sound both farther and faster than air does.
- Sound waves move approximately four times faster in water than in air.
- Above water, we are able to determine a sound’s direction by the minute difference between when a sound arrives at one ear, and when it arrives at the other.
- Under water, sounds arrive at our ears almost simultaneously, making it difficult to determine the direction from which a sound is coming.
This can be a problem when there is a boat over head, as it may be difficult to determine how close the boat is, or the direction it is traveling. The best thing to do when you hear a boat is to remain close to the bottom until the sound disappears and then surface by your dive float or your own dive vessel.
