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 rear axle was optional, and the 428 CJ/SCJ included a "traction lok" with a 3.91 or 4.30 ratio, 31 spline axle shafts and a nodular case. In 1970, the 3.91 ratio was a "traction-lok", while the 4.30 ratio was a Detroit Locker. Mach 1s came with upgraded suspension to varying degrees dependent upon powertrain choices. Big block cars had front shock tower reinforcement, thicker sway bars (no rear bar for 69), and heavier springs and shocks. 428 CJ/SCJ 4 speed cars also came with staggered rear shocks. Standard on Mach 1s was a fierce but cosmetic hood scoop that had