Ernst Mach of experimental physics concentrated on the interference, diffraction, polarization and refraction of light in different media under external influences. From there followed important explorations in the field of supersonic fluid mechanics. Mach and physicist-photographer Peter Salcher presented their paper on this subject in 1887; it correctly describes the sound effects observed during the supersonic motion of a projectile. They deduced and experimentally confirmed the existence of a shock wave of conical shape, with the projectile at the apex. The ratio of the speed of a fluid to the local speed of sound "v"/"v" is now called the Mach number. It
Ford Mustang Mach 1 (without Ram Air) remained optional on every model. Chart does not reflect the Boss 351 variant of the 351 Cleveland or 250cid I6, as neither were available in the Mach 1 package. The 1972 R-code 351HO package - essentially the solid-lifter Boss 351 motor from 1971 with a reduction in compression from 11.0:1 to 8.8:1 - is listed here, as it was available with the Mach 1 package that year. The Mach 1 name continued with the advent of the Mustang II in 1974. The downsized vehicle - fitted with the 2.8 L V6 rated at - outsold the Mach