Worked example
Find average speed
A car travels 150 km in 3 hours. What is its average speed?
- Use average speed = total distance ÷ total time.
- Substitute 150 km and 3 h.
- 150 ÷ 3 = 50.
Answer The average speed is 50 km/h.
Physics / Science
Motion
Describe journeys using distance, time, speed and acceleration.
Understand the concept
Motion occurs when an object changes position. Distance and speed describe how far and how quickly it moves, while displacement and velocity also include direction.
At higher grades, acceleration describes how velocity changes with time. Tables, graphs and equations help us compare journeys even when an object does not move at a constant speed.