Which of the following road surfaces freezes first?
Answers
A tunnel
An intersection
A bridge
The Correct Answer and Explanation is :
The correct answer is a bridge.
Explanation:
Bridges freeze first because of their unique construction and exposure to the elements. Unlike regular road surfaces, which are built on the ground and insulated by the earth, bridges are elevated structures with air circulating around them on both the top and bottom. This exposes the entire surface of the bridge to colder air, allowing the temperature to drop more rapidly compared to regular roads.
In contrast, roads on the ground are insulated by the earth beneath them, which retains heat and delays freezing. The combination of the cold air from above and the warmth from the earth below keeps the road surface on the ground warmer for longer than a bridge. Additionally, during the winter, bridges are often the first places where frost or ice begins to form, as they cool down more quickly than other types of road surfaces.
Why tunnels and intersections are less prone to freezing first:
- Tunnels: Tunnels are typically surrounded by the earth, which provides insulation. The temperature inside tunnels is more stable because the surrounding rock or soil moderates temperature fluctuations. While tunnels can still experience freezing conditions, they are less likely to freeze as quickly as a bridge.
- Intersections: Intersections may freeze due to increased traffic and the mixing of different road types, but they are not as prone to freezing first as bridges. While intersections may accumulate more ice due to sudden changes in traffic flow or water runoff, the ground temperature and lack of exposure to cold air are factors that help delay freezing compared to bridges.
In summary, bridges freeze first due to their exposure on both sides to cold air, which allows them to cool faster and create hazardous driving conditions more quickly than roads, tunnels, or intersections.