Stopping Distance = Thinking Distance + Braking Distance
The thinking distance is how far a car travels before the driver
brakes. It is affected by:
 the car's speed
 tiredness
 the weather (cloudy/foggy)
The braking distance is how far a car travels during braking. It is
affected by:
 the car's speed
 the road conditions (wet/icy)
 the wear on the brakes or tyres
If a car brakes too hard it may skid.