The distance, over which you can bring a car to a stop, the stopping distance, depends on four factors:

	The speed at which you are traveling
	The thinking distance - the time it takes you to think about stopping and hit the brakes
	The braking distance - the time it takes for the car to come to a stop after you have applied the brakes
	The weather conditions - dry roads mean shorter braking distances, wet and icy mean longer braking distances

The following diagram shows overall stopping distances at a variety of speeds when the road surface is dry. If the road were wet the stopping distance would be twice the distance, on icy roads the stopping distance would be ten times as great.