Final answer:
A speed limit is the legal maximum speed vehicles may travel under ideal conditions. It is critical for safety and legal reasons to adhere to posted speed limits. The de jure speed limit is the legal limit, while de facto speed limit may refer to the speed at which enforcement action is taken.
Step-by-step explanation:
A speed limit is the maximum speed at which a vehicle may legally travel on the road under ideal conditions. Ideal conditions suggest the road is dry, visibility is good, and the weather is fair. Under such conditions, the speed limit is set based on what is deemed as safe travel for the general public, which takes into account the design and condition of the road, as well as traffic conditions.
For example, on interstate highways, the limit is often around 100 km/h, which converts to approximately 27.8 m/s and 62 mi/h.It is important to note the difference between the de jure (legal) speed limit, which is posted on the roadside signs, and the de facto (actual) speed limit enforced by police officers, which might allow for a small margin above the posted limit before a motorist is pulled over.
Nonetheless, exceeding the legal speed limit can result in fines, penalties, and could potentially be dangerous, leading to accidents. When driving, especially through intersections or around curves, it is critical to adhere to these limits to maintain control of the vehicle without relying solely on the aid of friction between the tires and the road.