Summary
The rate of change in geometry often involves understanding how distance changes over time, as shown in travel graphs.
- Travel Graph — a graph showing distance travelled over time. Example: A graph where the x-axis represents time and the y-axis represents distance.
- Stationary Period — a time when the distance does not change. Example: A horizontal line on a distance-time graph.
- Constant Speed — when an object moves at a steady rate. Example: A straight line on a distance-time graph.
- Acceleration — when the speed of an object increases over time. Example: A curved line getting steeper on a distance-time graph.
- Deceleration — when the speed of an object decreases over time. Example: A curved line becoming less steep on a distance-time graph.
Exam Tips
Key Definitions to Remember
- Travel Graph
- Stationary Period
- Constant Speed
- Acceleration
- Deceleration
Common Confusions
- Confusing acceleration with constant speed
- Misinterpreting a horizontal line as movement
Typical Exam Questions
- What does a horizontal line on a distance-time graph indicate? It indicates a stationary period.
- How can you tell if an object is accelerating on a distance-time graph? The line is getting steeper over time.
- What does a straight line on a distance-time graph represent? It represents constant speed.
What Examiners Usually Test
- Understanding of how to read travel graphs
- Ability to identify periods of acceleration and deceleration
- Calculating speed from a distance-time graph