Ernst Mach (1838-1916)

Ernst Mach, Austrian physicist showed that when an object crosses the speed of sound, there is a loud sound called a sonic boom. Today we know that loud sonic booms are produced when a supersonic jet crosses the speed of sound. To honour the scientist the speed of supersonic aircraft is today given in terms of Mach numbers. These numbers relate the speed to the speed of sound. Thus, an aircraft travelling at Mach 2 has a speed double that of sound.

Copyrighted Ratna Sagar P. Ltd., 2006