Definition
Speed
Speed tells how much distance is covered in each unit of time.
What it means
If two riders travel the same distance, the one who takes less time has the greater average speed. If they use the same time, the one who travels farther is faster.
Remember it
Speed links distance to time: distance for each unit of time.
Example
A runner covers 2,400 m in 12 minutes. Average speed = 2,400 ÷ 12 = 200 m/min.
Watch for
A speed such as 20 km/h says how fast, not which direction; direction is not part of speed.
Common mix-up
Use total elapsed time, including stops, when a problem asks for average speed over the entire trip.
Exact meaning
Speed is the rate at which distance changes with time. For a whole journey, average speed equals total distance travelled divided by total elapsed time, using units such as kilometres per hour (km/h) or metres per second (m/s). Speed does not include direction.