Thinking distance

The distance travelled during the reaction is the thinking distance; the distance travelled after the brakes are applied is the braking distance.

The distance travelled during this response is the thinking distance. Second, once the brakes have been applied, the moving vehicle slows down but continues travelling until it stops. This is the braking distance.

Thinking distance is the distance travelled during the driver’s thinking time. A longer reaction time means the vehicle moves further before braking begins. Tiredness, alcohol or drugs can lengthen reaction time; age can also influence it.

During this reaction time, the vehicle continues at approximately its original speed and covers the thinking distance. It then slows while the brakes act, covering the braking distance.