Science
Speed and velocity.
Definition
Speed is the rate at which an object covers distance and is a scalar quantity (magnitude only). Velocity is a vector quantity that includes both the speed and the direction of motion. An object can have constant speed but changing velocity if its direction changes.
Examples
Real-world.
- 1 A car's speedometer reading 60 mph (speed) versus saying '60 mph north' (velocity)
- 2 A runner completing a lap around a 400 m track in 60 s has speed but zero average velocity
- 3 The International Space Station traveling at 7.66 km/s in a specific orbital direction
Key Fact
Speed = distance/time; Velocity = displacement/time (vector)