- A distance-time graph shows how the distance of an object (from a point) varies over time:
Graphs showing how the distances travelled by three objects vary over time
- A horizontal line means stationary
- A straight line means constant speed
- If the gradient increases the object is speeding up (accelerating)
- If the gradient decreases the object is slowing down (decelerating)
- If the line is going down, the object is moving backwards
When you come across any graph, look carefully at what is plotted on each axis and think for a while about what the graph is showing you.
Distance-time graphs are also known as position-time graphs or displacement-time graphs. Don’t be fooled by these different names: they describe the same kind of things.