How is "stopping distance" affected by speed?

Stopping distance is fundamentally affected by speed due to the principles of physics, particularly the relationship between speed and the kinetic energy of a vehicle. As a vehicle's speed increases, its kinetic energy also rises significantly, which in turn requires a greater distance to come to a complete stop.

The stopping distance includes both the reaction distance (the distance covered while the driver reacts and begins to brake) and the braking distance (the distance covered while the vehicle is decelerating to a stop). Since the reaction distance directly correlates with speed—higher speeds mean longer distances traveled during the driver's reaction time—the overall stopping distance naturally increases.

Moreover, the braking distance itself is influenced by speed, following the formula where the braking distance increases with the square of the speed. This means that if a vehicle's speed doubles, the braking distance is not just doubled, but quadrupled. Therefore, as speed increases, the total stopping distance increases, which is vital for ensuring safety on the road.

Understanding this concept is crucial for safe driving practices, as it emphasizes the importance of maintaining appropriate speeds, especially in conditions requiring quick stops.