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
Mach Five 345 horsepower, and cost between $75,000 and $125,000 each. The Petersen Automotive Museum in Los Angeles, California has a mid-engine prototype of the Mach Fives in its collection. The Mach Five appears in the live-action film adaptation "Speed Racer", directed by the Wachowski brothers, produced by Joel Silver, and released by Warner Bros. Pictures. The Mach Five is an actual vehicle and used in the major race of the film. Instead of being driven on pavement, it was hung from a crane and had its effects computer-generated. Along with the Mach Five, the movie features the "Mach 4" and the