Final answer:
The optimal way to achieve traction on snowy roads is by using winter tires that create more friction. Friction is the force that provides the necessary grip and control for a vehicle on slippery surfaces, and without it, a vehicle may continue in a straight line off the road due to reduced or absent radial friction.
Step-by-step explanation:
The best way to get traction on snow-packed roads is to use tires that are designed for winter conditions, which create more friction with the road surface compared to summer tires. This increase in friction is crucial as it allows for better grip and control of the vehicle. For example, in sports such as rock climbing, more friction is desirable between the climbing shoes and the rock surface to prevent slipping and ensure safety.
It's important to understand that traction is a result of friction between the tire and the road surface. On icy roads, friction can be significantly reduced, leading to a loss of traction. This is why specially designed winter tires with deeper treads and rubber compounds that remain flexible at lower temperatures are essential for maintaining control. When a car encounters ice, radial friction with the tires provides the centripetal force required to maintain the car's path around a curve. If the friction is nearly zero, as is the case on ice, then the car will continue in a straight line off the road, following Newton's first law.