Mach number(redirected from Mach 2)
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Related to Mach 2: Concorde
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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(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]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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 American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The ratio of the velocity of a body to that of sound in the surrounding medium.
Dictionary of Military and Associated Terms. US Department of Defense 2005.
A unit of velocity. Mach 1 is the speed of sound; Mach 5 is described as hypersonic.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited