Part 1: Understand the science

Learning intentions: Explain how speed, reaction time and road conditions affect stopping distance; distinguish between thinking distance, braking distance and total stopping distance; use evidence to explain safer road decisions.

Success criteria: I can define the three distances, interpret data accurately, explain the effects of risk factors and justify a safe response.

Road-safety note: These are simplified examples for science education. They are not driving instructions and should not be used to encourage learners to drive.

1. Draw and label a three-part stopping-distance diagram. Show the vehicle’s starting point, the moment the hazard is noticed, the start of braking and the final stopping point. Label thinking distance, braking distance and total stopping distance.

2. Match each technical term to its meaning.

A. Thinking distance

B. Braking distance

C. Total stopping distance

D. Deceleration

1. The distance travelled while the brakes slow the vehicle to a stop.

2. The distance travelled from noticing a hazard to applying the brakes.

3. A decrease in velocity.

4. Thinking distance plus braking distance.

Answers: A–____ B–____ C–____ D–____

Simplified example data: The figures below are illustrative averages, not universal exact values. Real stopping distances vary with the vehicle, driver, tyres, brakes, road surface, weather, gradient and load.

Speed (mph) Thinking distance (m) Braking distance (m) Total stopping distance (m)

20 6 6 12

30 9 14 23

40 12 24 36

50 15 38 53

60 18 55 73

3. Use the equation total stopping distance = thinking distance + braking distance. Calculate the total stopping distance at 40 mph. Show your working.

4. Describe two patterns in the data. Include one pattern about thinking distance and one about braking distance.

5. Compare the total stopping distances at 30 mph and 60 mph. How much greater is the 60 mph distance, and what does this suggest about risk?

Word bank: reaction time, speed, hazard, thinking distance, braking distance, total stopping distance, deceleration, friction, grip, wet road, safe gap, visibility.

Part 2: Make safe, evidence-based decisions

Sentence starters: “The safest response is…” “This reduces risk because…” “The data shows…” “Braking distance may increase when…”

6. A vehicle is approaching a queue on a wet road. What is the safest response? Explain using friction, braking distance and at least one other factor.

7. A driver is tired and distracted by a phone notification. What is the safest response? Explain how reaction time and thinking distance affect the risk.

8. A vehicle is following very closely behind another vehicle. What is the safest response? Explain why a larger gap is important using total stopping distance.

9. Write a short road-safety explanation for a newly qualified driver: Why can wet conditions and tiredness increase stopping risk? Use at least three technical terms and two pieces of evidence from the data or scenarios.

10. Exit ticket

One key fact I have learned:

One safety action that reduces risk:

My confidence rating: 1 2 3 4 5 Circle one.

Teacher answer key

1. Diagram: The correct order is starting point or hazard noticed, thinking distance, brakes applied, braking distance, final stopping point. Total stopping distance runs from the hazard being noticed to the vehicle stopping.

2. Matching: A–2, B–1, C–4, D–3.

3. Calculation: Thinking distance + braking distance = total stopping distance. At 40 mph: 12 m + 24 m = 36 m.

4. Indicative answers: Thinking distance increases as speed increases: 6 m at 20 mph to 18 m at 60 mph. Braking distance also increases, and it increases more rapidly: 6 m at 20 mph to 55 m at 60 mph. Total stopping distance increases as speed increases.

5. Calculation and interpretation: At 30 mph the total is 23 m. At 60 mph the total is 73 m. The difference is 73 − 23 = 50 m. The higher speed gives much less time and distance to respond, so the risk of collision is greater.

6. Wet road: Safest responses include reducing speed early, increasing the gap and avoiding sudden braking or steering. Water can reduce friction and grip, increasing braking distance. The queue means more stopping distance is needed.

7. Tired or distracted driver: The safest response is to stop the journey safely and remove the distraction, or regain full attention before continuing. Tiredness and distraction can increase reaction time, so thinking distance increases. The vehicle may travel further before braking begins.

8. Following too closely: The safest response is to increase the gap and reduce speed if necessary. A larger gap provides more time for reaction and more space for total stopping distance. If the vehicle ahead brakes suddenly, a small gap may not be enough.

9. Indicative response: Wet conditions can reduce friction and grip, which can increase braking distance and therefore total stopping distance. Tiredness can increase reaction time, so thinking distance increases. The simplified data shows total stopping distance rising from 23 m at 30 mph to 73 m at 60 mph. A safer response is to reduce speed, increase the gap and avoid driving when tired or distracted.

10. Exit ticket: Accept accurate key facts such as “total stopping distance equals thinking distance plus braking distance”. Suitable safety actions include reducing speed, increasing the gap, avoiding distractions or not travelling when tired. Confidence rating is the learner’s own assessment.