Topic 2.4 - Stopping Distance

Question 1

How to measure human reaction time?

Answer 1

• ruler drop test

Question 2

What are the typical ranges of human reaction time?

Answer 2

• 0.2 - 0.9

Question 3

Equation for stopping distance:

Answer 3

• thinking distance + braking distance

Question 4

Factors affecting stopping distance:

Answer 4

• the mass of the vehicle
• the speed of the vehicle
• the driver’s reaction time
• the state of the vehicle’s brakes
• the state of the road
• the amount of friction between the tyre and the road surface

Question 5

Factors affecting a driver’s reaction time:

Answer 5

• drugs
• distraction

Question 6

Explain the dangers caused by large decelerations and estimate the forces involved in typical situations on a public road

Answer 6

Dangers:
- Injury to Occupants
- Secondary Collisions

Estimate the forces:
- Force exerted on brakes
- Force experienced by occupants