Did You Know? Sound Travels Four Times Faster In Water Than In Air

The speed at which sound travels in water is astounding—nearly four times faster than in air! This isn't your imagination!

Sound moves with surprising swiftness beneath the waves, creating an underwater world alive with echoing clicks, songs, and rumbles! Photo Credit: George Retseck

Not only does sound travel, but it also races—and it does so astonishingly quickly in water! If you’ve ever heard an odd sound while submerged, you may have noticed how it seems to travel through the water swiftly and clearly. The speed at which sound travels in water is astounding—nearly four times faster than in air! This isn’t your imagination!

Sound waves move through the atmosphere at a speed of around 343 meters per second, or 1,125 feet per second. However, they move at over 1,480 meters per second in the water! This significant difference results from the tightly packed nature of water molecules as opposed to the free, dispersed molecules seen in the atmosphere. Because molecules in liquids can transmit vibrations more quickly, sound travels at breakneck speed.

Particularly for marine animals like dolphins and whales, this fast speed has practical effects. Sound is vital to these animals’ existence. To find their way and communicate in the deep ocean, where light cannot penetrate, they use echolocation, a natural sonar system. Because of their great speed and range in water, their clicks and calls can reverberate for kilometres, allowing them to “see” through sound.

Gaining knowledge of the science of sound in water also assists humans by enhancing technology like sonar and facilitating underwater exploration. The next time you jump into the ocean or a pool, keep in mind that sound is travelling at breakneck speed all around you—just another illustration of the incredible physics that lies beneath the waves!