Why are the inner lanes lower than the outer lanes on curved roads?
1 Answers
The outer lanes are higher than the inner lanes on curves to ensure that the combined force of the support force and gravity acts as part of the centripetal force, thereby enhancing traffic safety. When a car turns, it requires centripetal force. If the turn is sharp, this force needs to be greater. Relying solely on ground friction is insufficient to facilitate a smooth turn, so the outer side of the road is built higher while the inner side is lower. This design ensures that when a car passes through, the inclined surface of the road directs the resultant force toward the inner side of the curve, acting as the car's centripetal force and aiding in a smooth turn. When turning on wet, snowy, or muddy roads, drivers should reduce speed in advance by utilizing the engine's drag resistance and proceed slowly. Avoid sudden steering or hard braking. When turning uphill, if other vehicles are stuck due to slipping and blocking the curve, the driver should pull over to the right and wait for the vehicles ahead to pass before proceeding. When encountering slippery downhill turns, take precautions to prevent the car from sliding and causing collisions.