stopping distances

• Describe how human reaction times are measured 


  Reaction time is usually measured using a reaction time test, where a person is asked to respond as quickly as possible to a visual or auditory stimulus
• Recall typical human reaction times

  0.2 seconds (s) to 0.9 s.
• Describe the link between stopping distance, thinking distance and braking distance


  Stopping distance= thinking distance + braking distance
• Recall the factors that affect braking distance

  • Vehicle condition - e.g. worn tyres or poor brakes.
  • Road condition - wet or icy roads make it harder to decelerate.
  • Vehicle mass - a heavy vehicle, such as a lorry, takes longer to stop.
• Recall the factors that affect thinking distance

  • Alchol
  • Other drugs and some medicines
  • Distractions, such as a mobile phone
  • Speed
• describe the factors affecting a driver's reaction time including drugs and distractions


  taking some medications can make you feel drowsy, resulting in an increased reaction time