Speed
Speed is the rate of motion expressed as distance moved per unit of time. Speed is a scalar quantity; the equivalent vector quantity is known as velocity.
Units of speed include:
- meter per second, (symbol m/sec), the SI derived unit
- kilometer per hour, (symbol km/h or kph)
- mile per hour, (symbol mph)
- knot (nautical miles per hour)
- Mach, where Mach 1 is the speed of sound; Mach n is n times as fast.
Speed is also:
- A slang term for amphetamines
- An American film: see Speed (movie)
