Final answer:
The sign that depicts a truck going downhill is a warning sign indicating caution for a steep slope.
Step-by-step explanation:
The sign that depicts a truck going downhill is a warning sign indicating caution for a steep slope. This sign is commonly used to alert drivers that they are approaching a downhill section of the road where they may need to control their speed or apply their brakes more frequently.
For example, if a truck with a mass of 1.2 tons is parked at the top of a hill that is 150 m high, the truck will start rolling downhill due to the force of gravity. As the truck descends, it will accelerate and gain momentum, making it necessary for the driver to exercise caution and use their brakes effectively to navigate the slope safely.
In this case, the sign can indicate the presence of a steep slope ahead, requiring drivers to adjust their speed accordingly and be prepared for potential hazards associated with descending the hill.