Certified Treecare Safety Professional (CTSP) Practice Exam

Which factor is most likely to affect the stopping distance of a truck?

1. Traffic light changes

2. Road conditions

3. Driver's experience

4. Type of load carried

The correct answer is: Road conditions

The stopping distance of a truck is significantly influenced by road conditions. When road surfaces are wet, icy, or uneven, they can increase the friction that the tires have with the ground, thereby lengthening the distance required for the truck to come to a complete stop. Factors like gravel, water, snow, and ice can greatly impair tire traction, leading to a longer stopping distance. While traffic light changes can prompt sudden stops, they do not inherently alter the physics of how the truck interacts with the road. The driver's experience plays an important role in how effectively they can respond to changing conditions, but it does not directly change the fundamental mechanics of stopping distance. Similarly, the type of load carried can affect the truck's overall weight and center of gravity, but the immediate influence on stopping distance primarily comes from how the truck engages with the road surface under various conditions. Therefore, when considering the primary factors affecting stopping distance, road conditions stand out as the most critical element.