Science & TechFact

Underwater, sound travels more than four times faster.

In air at 20 °C, sound covers 343 metres per second. In fresh water it is 1,481 m/s, in seawater about 1,500 m/s. The reason: water molecules sit tightly packed and pass the push along almost without delay. That is why whales hear across hundreds of kilometres and sonar measures distance from travel time.

Useful: When diving you can barely locate sounds: they reach both ears practically at the same moment.

Source: en.wikipedia.org

Akustik PhysikWasser

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