Forces
This lesson builds distance-time and velocity-time graphs for GCSE Physics.
Use the core lesson first, then match the exam-board guidance to your school route. Many pupils meet this content through Combined Science as well as Separate Physics.
What you will learn
Exam-board fit
Exact paper labels and specification-point numbering vary by board and cohort, so match this lesson to your school route before using past-paper questions.
Graph descriptions supplied on this page
Use the journey and trolley graph descriptions to practise gradient, area and motion language.
Clear explanation
On a distance-time graph, gradient represents speed. A steeper line means a greater speed; a horizontal line means stationary.
On a velocity-time graph, gradient represents acceleration. The area under the graph represents distance travelled.
Graph questions reward method: mark two clear points for gradient and split areas into rectangles and triangles when needed.
Key graph
Worked examples
Distance from a velocity-time graph
A car travels at 12 m/s for 5 s.
distance = area under velocity-time graph
area = 12 x 5 = 60
Quick checks
Choose an answer, then check your thinking.
1. What does the gradient of a distance-time graph represent?
2. What does the area under a velocity-time graph represent?
Practice questions
Question 1
A distance-time graph rises from 0 m to 40 m in 8 s. Calculate speed.
Reveal answer and marking guidance
Answer: 5 m/s.
Marking: Credit gradient = 40 ÷ 8 = 5 m/s.
Question 2
A velocity-time graph is horizontal at 6 m/s for 10 s. Calculate distance.
Reveal answer and marking guidance
Answer: 60 m.
Marking: Credit area = 6 x 10 = 60 m.
Question 3
A velocity changes from 2 m/s to 14 m/s in 6 s. Calculate acceleration.
Reveal answer and marking guidance
Answer: 2 m/s².
Marking: Credit gradient = change in velocity ÷ time = 12 ÷ 6 = 2 m/s².
Question 4
What does a horizontal line on a distance-time graph mean?
Reveal answer and marking guidance
Answer: The object is stationary.
Marking: Credit distance not changing as time passes.
Exam practice ladder
Answers and marking guidance
The exact practice answers are hidden under each question so you can try first. For this lesson, marks come from using the correct physics model, choosing the right equation where needed, keeping units with values, and explaining changes with precise words such as transfer, resultant force, acceleration, evidence and uncertainty.
Common mistakes
- Confusing distance-time and velocity-time gradients.
- Using the whole graph as one shape when it needs splitting.
- Calling a flat distance-time graph constant speed.
- Forgetting graph units.
Exam-board guidance
All supported routes assess the core physics idea, but they may group topics, practicals and paper wording differently.
AQA GCSE Physics
AQA GCSE Physics: use this lesson for distance-time and velocity-time graphs, then check whether your class is taking Separate Physics or Combined Science.
OCR GCSE Physics
OCR GCSE Physics: the core physics idea is shared, but Gateway and Twenty First Century may organise questions differently.
Pearson Edexcel GCSE Physics
Pearson Edexcel GCSE Physics: practise the concept, the equation use and the practical language because questions often connect them.
Eduqas GCSE Physics
Eduqas GCSE Physics: learn the core explanation and practise applying it to unfamiliar contexts, data and practical questions.
WJEC Wales
WJEC Wales: check whether your class is using the current GCSE Physics route or a newer science route, then use this lesson for the shared physics idea.
CCEA GCSE Physics
CCEA GCSE Physics: connect the idea to your unit and remember that practical skills are assessed directly.
Extension challenge
Sketch a velocity-time graph with acceleration, steady speed and deceleration, then calculate a possible total distance.
Reveal answer
Example answer: A strong extension response names the physics model, uses accurate units and explains why the evidence supports the conclusion.
Next lesson
Next, continue with Newton's Laws and Resultant Forces.