When driving at 20 mph on packed snow, you should maintain a following distance of at least _.
The Correct Answer and Explanation is :
The correct answer is:six car lengths
When driving at 20 mph on packed snow, you should maintain a following distance of at least six car lengths or approximately six seconds. This extended following distance is crucial for maintaining safety in hazardous winter driving conditions. Here’s why:
1. Reduced Traction:
Packed snow significantly reduces tire traction, which is the friction between your tires and the road surface. With less traction, your vehicle requires a longer distance to come to a complete stop, especially at higher speeds. Even at 20 mph, packed snow can turn a routine stop into a potentially dangerous situation if you’re too close to the vehicle in front of you. The general rule of thumb is to increase your normal following distance in snowy conditions to at least double or triple the distance you would maintain on dry roads.
2. Extended Stopping Time:
When the road is covered in packed snow, stopping distances can increase by 4 to 10 times. For example, on dry pavement, a vehicle traveling at 20 mph requires around 40-50 feet to come to a complete stop. On packed snow, this distance can increase to over 150 feet or more. By maintaining a following distance of six car lengths (approximately 120-150 feet), you give yourself enough time to react and stop safely without rear-ending the vehicle ahead.
3. Visibility and Reaction Time:
Driving in snowy conditions can reduce visibility due to snow flurries or fog, which also requires drivers to be more cautious. Increasing your following distance gives you more time to react if the car in front of you brakes suddenly.
In summary, maintaining a six-second or six-car-length following distance when driving at 20 mph on packed snow provides the necessary buffer to avoid accidents. This cautious approach compensates for reduced traction and ensures safer driving in winter conditions.