Final answer:
When a car slides over a thin layer of water on the roadway, it's known as hydroplaning. This occurs under specific conditions such as low tire pressure, worn tread, or excessive speed and results in a significant reduction of traction and vehicle control.
Step-by-step explanation:
When your car slides on top of a thin layer of water between your tires and the road, especially when conditions such as low air pressure, bad tread, or speeding are involved, this is called hydroplaning or aquaplaning.
The rubber tires are unable to push away the water fast enough, resulting in a loss of contact with the road surface, which greatly reduces traction and can lead to loss of vehicle control.
Under circumstances where tire traction is compromised, such as on wet concrete or ice, the coefficient of friction between the tire and the road surface is significantly reduced. In the case of ice, for example, if we assume that μ (the coefficient of friction) is 0.100, it is similar to that of shoes on ice, indicating very low traction. That's why cars can easily slide off the road when they encounter icy patches, following a path tangent to the curve they were negotiating.
Friction is generally important for maintaining control of a vehicle. Proper tire inflation and tread are critical for maximizing friction and ensuring safety. For example, choosing tires designed for icy conditions can create more friction with the road compared to standard summer tires, which can be desirable in winter driving situations.