Gradient of a Displacement-Time Graph
- Displacement-time graphs show the changing position of an object in motion
- They also show whether an object is moving forwards (positive displacement) or backwards (negative displacement)
- A negative gradient = a negative velocity (the object is moving backwards)
- The gradient (slope) of a displacement-time graph is equal to velocity
- The greater the slope, the greater the velocity
Worked example
A car driver sees a hazard ahead and applies the brakes to bring the car to rest.What does the displacement-time graph look like?
Examiner Tip
Don’t forget that velocity is a vector quantity; it has a size and a direction. If velocity is initially positive and then becomes negative, then the object has changed direction.
