Speed is the distance traveled per unit of time. It is how fast an object is moving. Velocity is the same as speed but also includes direction.
Speed Units Explained
- Meters per Second (m/s): The SI unit of speed and velocity.
- Kilometers per Hour (km/h): The most common unit of speed for road traffic, used in most of the world.
- Miles per Hour (mph): The standard unit of speed for road traffic in the US and UK.
- Knot (kn): A unit of speed equal to one nautical mile per hour. Used in meteorology, maritime, and air navigation.
- Mach: The ratio of the speed of a body to the speed of sound in the surrounding medium. Mach 1 is the speed of sound.
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Fun Fact: The speed of sound (Mach 1) isn’t constant! It changes with temperature. At 20°C (68°F) at sea level, it’s about 343 m/s (1,235 km/h or 767 mph).