Step 1 : Introduction to the question "7. Ernst Mach was a physicist who introduced the mach number. What is the mach number?"
...1. The number of burgers one can eat at McDonald's 2. The number of blades in a shaving razor 3. A measurement related to speed 4. The strength of a diamond Ernst Mach was an Austrian physicist and philosopher who introduced the concept of Mach number (named after him). The Mach number is a measurement of the ratio of the speed of a moving body to the speed of sound. When objects like aircraft or missiles travel at the speed of sound, the object's speed is measured using the unit Mach.
