Mach number which was also unit-first, and may have influenced the use of the term Mach. In the decade preceding faster-than-sound human flight, aeronautical engineers referred to the speed of sound as "Mach's number", never "Mach 1". Mach number is useful because the fluid behaves in a similar manner at a given Mach number, regardless of other variables. As modeled in the International Standard Atmosphere, dry air at mean sea level, standard temperature of , the speed of sound is . The speed of sound is not a constant; in a gas, it increases as the absolute temperature increases, and since atmospheric
David Mach David Mach David Mach (born 18 March 1956) is a Scottish sculptor and installation artist. Mach was born in Methil, Fife. His artistic style is based on flowing assemblages of mass-produced objects. Typically these include magazines,vicious teddy bears,newspapers, car tyres, match sticks and coat hangers. Many of his installations are temporary and constructed in public spaces. One example of his early magazine pieces, "Adding Fuel to the Fire", was an installation assembled from an old truck and several cars surrounded and subsumed by about 100 tons of magazines, individually arranged to create the impression that the vehicles were being caught