What is the speed limit on urban roads?

[LeonardoDella]

Urban roads generally have a speed limit of 40 km/h. The following are the hazards of speeding: Weakened perception of changes inside and outside the vehicle: Excessive speed makes it difficult to obtain sufficient road information, increasing the risk of traffic accidents. For example, when a car travels at 50 km/h, it moves 1.39 meters in 0.1 second, and objects outside the window pass by in a flash. However, it takes 0.4 second for a person to sense a target within their field of vision and an average of 1 second to clearly see an object. Driver's spatial perception weakens: The focus point moves forward, the field of vision narrows, and clarity deteriorates, making driving dangerous. The faster the speed, the farther the focus point moves. At speeds above 50 km/h, the focus point is often 305-601 meters away. It becomes difficult to recognize small and slowly changing objects, and by the time they are noticed, it may be too late to react.