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) 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 American servicemen being held hostage by terrorists. Before he leaves, he receives a disk documenting evidence that the Vice-President has been trying to revive the American economy by causing a war in the Balkans. He announces his plans at Washington Dulles International Airport to show it to both sides in