Which factor increases the required stopping distance for a vehicle?

The required stopping distance for a vehicle is influenced by both its speed and weight. As speed increases, a vehicle will require a longer distance to come to a complete stop because the momentum is greater; the faster the vehicle is traveling, the more energy it has, and this energy must be dissipated when braking. Similarly, the weight of the vehicle plays a critical role. Heavier vehicles have more inertia, which means more force is needed to stop them compared to lighter vehicles. Therefore, as either the speed or the weight of the vehicle increases, the stopping distance required also increases.

On the other hand, while factors such as road conditions do affect stopping distance, the option of changing road conditions to wet primarily relates to friction rather than the inherent characteristics of the vehicle itself. The impact of speed and weight is more direct and fundamental to understanding stopping distances in general.