What factor does NOT influence vehicle stopping distances?

The factor that does not influence vehicle stopping distances is the time of day. Stopping distance is primarily affected by several critical factors, including weather conditions, vehicle speed, and road conditions.

Weather conditions, such as rain, snow, or fog, can significantly affect traction and visibility, which in turn impact how quickly a vehicle can come to a stop. Vehicle speed is also a crucial factor, as the faster a vehicle is traveling, the longer the time and distance it will take to bring it to a complete stop. Lastly, road conditions, like whether the surface is wet, dry, or icy, also play a pivotal role in determining stopping distances, as they directly influence the friction between the tires and the road.

While the time of day may affect visibility to some extent (like driving at night requiring good headlights), it does not have a direct effect on how quickly a vehicle can stop under various circumstances. Thus, the time of day does not alter the fundamental dynamics of stopping distances in the way the other factors do.