Final answer:
The roadway is particularly hazardous when wet, and the first half-hour of rain increases this hazard due to the mixture of rainwater with oil residues on the road. Wet conditions lead to increased stopping distances for vehicles compared to dry pavement, and reaction time also contributes to the total stopping distance.
Step-by-step explanation:
The roadway can indeed be particularly hazardous when wet, and this is especially true during the first half-hour of rain. During this time, oil and gasoline, which have leaked onto the road, are not yet washed away, making the surface even more slippery. Moreover, the stopping distance for a vehicle on wet pavement increases compared to dry conditions due to decreased friction. Reaction time also plays a crucial role in determining the overall distance a vehicle travels before coming to a complete stop after the driver perceives the need to halt.
Tests on different surfaces have shown that a car on wet concrete has a greater stopping distance than on dry concrete, while the most dangerous condition is likely when driving on ice. A light rain can make the road more slippery due to the mixture of water with oil and gasoline residue, and while a heavy rain might eventually wash away such residues, it will still require a longer stopping distance due to reduced tire traction. Therefore, it's important for drivers to adjust their driving behavior in wet conditions to maintain control and safety on the road.