The **braking distance** is the space a vehicle travels from the moment the brake is applied until it comes to a complete stop. This distance can vary due to several factors, and one of the most important is the **weather**. When there is **snow or ice on the road**, the surface becomes slippery, which significantly increases the braking distance. This is because the tires have less grip in these conditions, making it more difficult for the vehicle to stop quickly.

Therefore, it is crucial to take into account the weather and road conditions when calculating the braking distance, as the presence of snow or ice may require the vehicle to need more space to stop safely.