mach number
n.
number which shows the speed of an object in relation to the speed of sound
Mach number
Mach number (Ma) (pronounced: , see
IPA) is a dimensionless measure of relative
speed. It is defined as the speed of an object relative to a
fluid medium, divided by the
speed of sound in that medium: where is the Mach number is the velocity of the object relative to the medium and is the velocity of sound in the medium
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Mach number
Noun
1. the ratio of the speed of a moving body to the speed of sound
(hypernym) ratio
Mach Number
MACH NUMBER
The ratio of true airspeed to the speed of sound; e.g., MACH .82, MACH 1.6.
(See AIRSPEED.)