Mach number

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noun \ ˈmäk- \

Definition of Mach number

:a number representing the ratio of the speed of a body (such as an aircraft) to the speed of sound in a surrounding medium (such as air)

Origin and Etymology of mach number

Ernst Mach †1916 Austrian physicist


Medical Dictionary

Mach number

play
noun \ ˈmäk- \

medical Definition of Mach number

:a number representing the ratio of the speed of a body to the speed of sound in a surrounding medium (as air)
  • a Mach number of 2 indicates a speed that is twice that of sound

Learn More about mach number


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