Stopping distances
The following distances apply to dry weather in a well maintained car. The thinking distances are for the average driver paying full attention to the road.
It doesn't matter how good a car's engineering and brakes are, there is nothing they can do to contradict the laws of physics. This increase in speed will inevitably increase stopping distance.
| Speed | Thinking distance | Braking distance | Total stopping distance |
|---|---|---|---|
| 20MPH | 1.5 car lengths | 1.5 car lengths | 3 car lengths |
| 30MPH | 2.5 car lengths | 3.5 car lengths | 6 car lengths |
| 40MPH | 3 car lengths | 6 car lengths | 9 car lengths |
| 50MPH | 3.5 car lengths | 12.5 car lengths | 13 car lengths |
| 60MPF | 4.5 car lengths | 13.5 car lengths | 18 car lengths |
| 70MPH | 5 car lengths | 19 car lengths | 24 car lengths |
The two second rule
If you find it hard judging the correct distance between you and the car in front, use the two second rule.
As the car in front passes a marker say "only a fool breaks the two second rule" this should take two seconds. You should have finished saying it before you pass the same marker. In bad weather you will need to double this distance.
For more information call 0845 2302882 or email tfb@buckscc.gov.uk
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