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 2 (film) United States Presidential Seal on the cabin divider walls. Several movie errors were shown: the steering column clearly shown onscreen is a vertical type, unlike Concorde's one is shaped like the letter "m". It also features advanced LCD primary flight displays, but Concorde's display is just dials or analog style. Mach 2 (film) Mach 2 is a 2001 American direct-to-video action disaster thriller film directed by Fred Olen Ray. It was the first film to feature the airliner Concorde being hijacked. U.S. Senator Stuart Davis, running against the Vice-President, plans a trip to the Balkans to negotiate the release of