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Related to Mach number: Drag divergence Mach number
Mach numberalso mach number (mäk)
n. Abbr. M
The ratio of the speed of an object to the speed of sound in the surrounding medium. For example, an aircraft moving twice as fast as the speed of sound is said to be traveling at Mach 2.
[After Ernst Mach.]
(Units) (often not capital) the ratio of the speed of a body in a particular medium to the speed of sound in that medium. Mach number 1 corresponds to the speed of sound. Often shortened to: Mach
[C19: named after Ernst Mach]
a number indicating the ratio of the speed of an object to the speed of sound in the medium through which the object is moving. Abbr.: M
[after E. Mach]
Ernst, 1838–1916, Austrian physicist.
The ratio of the speed of a body to the speed of sound in a particular medium. For example, an aircraft flying through air at twice the speed of sound has a Mach number of 2.
The ratio of the velocity of a body to that of sound in the surrounding medium.
A unit of velocity. Mach 1 is the speed of sound; Mach 5 is described as hypersonic.