Is 911 kilometers per hour as fast as The Speed of Sound?
It's about three-fourths as fast as The Speed of Sound
The speed of The Speed of Sound is about 1,230 kilometers per hour.
(in dry air at 20°C)
The speed of sound in dry air at 20°C (68°F) is 343 m/s. Air is a relatively poor acoustic conductor, however, as sound will travel at speeds of between 5,390 kilometers per hour to 5,620 kilometers per hour in water, depending on its salinity.
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