Science
What is Velocity?
Velocity is the speed of an object in a specific direction. Unlike speed, which is just a number, velocity tells you both how fast something moves and which way it's going — for example, 50 km/h heading east.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains velocity.
Key things to understand
- 1Velocity = speed + direction. It's a vector quantity (magnitude and direction).
- 2Two objects can have the same speed but different velocities if they move in different directions.
- 3A change in velocity — speeding up, slowing down, or changing direction — is acceleration.
- 4An object moving at constant speed in a circle has a changing velocity, because its direction keeps changing.
Frequently asked questions
- How is velocity different from speed?
- Speed is just how fast (a number); velocity is how fast in a particular direction. Going 30 km/h is a speed; going 30 km/h north is a velocity.
- Can velocity change while speed stays the same?
- Yes — if you turn a corner at a constant 30 km/h, your speed is unchanged but your direction (and so your velocity) changes.
- What is the unit of velocity?
- The same as speed — metres per second (m/s) or kilometres per hour (km/h) — but always with a direction stated.