4.5.6.3.1 Stopping Distance

Question 1

Stopping distance:

Answer 1

• the stopping distance of a vehicle is the sum of the distance the vehicle travels during the drivers reaction time (thinking distance) and the distance it travels under the braking force (braking distance) - sum of the thinking distance and the braking distance
• the distance needed for a vehicle travelling at a given speed to stop

Question 2

Thinking distance:

Answer 2

the distance the vehicle will travel during the driver’s reaction time

Question 3

Stopping distance for a vehicle travelling at 30mph (13m/s):

Answer 3

23m

Question 4

Stopping distance for a vehicle travelling at 50mph (22m/s):

Answer 4

53m

Question 5

Stopping distance for a vehicle travelling at 70mph (31m/s):

Answer 5

96m

Question 6

Reaction time:

Answer 6

time taken for the driver to spot the hazard, make a decision and move their foot to the brake

Question 7

Typical reaction times:

Answer 7

0.2s - 0.9s

Question 8

Factors that might affect reaction time:

Answer 8

• tiredness, fatigue
• drugs
• alcohol - the driver being under the influence of alcohol which would increase their reaction time and therefore increase the thinking distance increasing the overall stopping distance due to not being able to spot the hazard as quickly

Question 9

Factors that might affect thinking distance:

Answer 9

• alcohol - the driver being under the influence of alcohol which would increase their reaction time and therefore increase the thinking distance increasing the overall stopping distance due to not being able to spot the hazard as quickly
• drugs
• fatigue
• distractions e.g. mobile phone, kids, radio, listening to music
• age
• speed of vehicle
• ability to focus/distractions
• (weather e.g. lack of ability to see/spot accident and respond to it)