Question 1: Braking distance is the distance a vehicle travels from the moment the brakes are applied until it comes to a complete stop. It depends on factors such as initial speed, vehicle mass, brake efficiency, and road conditions.

Answer: Braking distance is the distance travelled by a vehicle from brake application to stopping, influenced by speed, mass, brake effectiveness, and road conditions.

Question 2: Explain why a vehicle travelling at a higher speed generally has a longer braking distance.

Answer: Because kinetic energy increases with the square of speed, requiring more work to dissipate, resulting in a longer braking distance.

Question 1: Define 'braking force' and describe how it affects braking distance.

Answer: Braking force is the force exerted by the brakes to reduce vehicle speed; greater braking force reduces braking distance.

Question 2: List three factors that can increase the braking distance of a vehicle.

Answer: Higher initial speed, increased vehicle mass, poor road conditions (e.g., wet or icy surface).

Question 1: Calculate the braking distance for a car travelling at 20 m/s with a constant deceleration of 5 m/s². (Use the formula: d = v² / (2a))

Answer: d = 20² / (2 × 5) = 400 / 10 = 40 metres

Question 2: If a vehicle's initial speed is 15 m/s and it takes 3 seconds to come to a stop, what is its average deceleration? (Use the formula: a = v / t)

Answer: a = 15 / 3 = 5 m/s²

Question 1: Describe an experiment you could perform to investigate how road surface affects braking distance. Include variables, safety precautions, and expected outcomes.

Answer: Students could measure braking distances of a model vehicle on different surfaces (dry, wet, icy). Control variables include initial speed, vehicle mass, and brake type. Variables include surface type. Safety precautions involve wearing protective gear and ensuring a safe testing area. Expected outcome: longer braking distances on wet or icy surfaces due to reduced friction.

Question 1: A car manufacturer tests braking distances at different initial speeds. The data shows that at 10 m/s, the braking distance is 12 metres; at 20 m/s, it is 48 metres. Analyse the relationship between initial speed and braking distance, and explain if it supports the theoretical formula.

Answer: The data shows that braking distance quadruples when the initial speed doubles (from 10 to 20 m/s). This supports the formula d ∝ v², as braking distance is proportional to the square of the initial speed, confirming the theoretical relationship.

Question 2: In the context of vehicle safety engineering, explain how understanding braking distance influences the design of braking systems and road safety measures.

Answer: Understanding braking distance helps engineers design more effective brakes and develop safety standards, such as appropriate stopping distances and road surface treatments, to prevent accidents.