Speed of Sound

What is the sound barrier?

The sound barrier is the speed that an object must travel to exceed the speed of sound. The speed of sound is often used as a reference with which to measure the velocity of an aircraft. The speed of sound, 331 meters per second at 0°C, is Mach 1. Twice the speed of sound is Mach 2, three times the speed of sound is Mach 3, and so on.


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