Final answer:
The yellow light warns drivers that the signal is about to turn red and prepares them to stop if safe, not solely to clear the intersection. It contributes to slowing down traffic, pedestrian safety, and reducing accidents.
Step-by-step explanation:
The purpose of a yellow light at a traffic signal is to warn drivers that the light is about to change to red, not specifically to clear the intersection. This indication advises drivers to slow down and prepare to stop if it is safe to do so. The presence of a traffic signal itself helps to regulate the flow of both vehicular and pedestrian traffic, contributing to enhanced safety. Signals compel vehicles to slow down, which might be difficult to enforce only with posted speed limits. In regards to pedestrian safety, it allows individuals, including students, the opportunity to cross the intersection without having to dodge traffic, when it is their turn. Lastly, a traffic signal can reduce the incidence of accidents by better managing in traffic density and providing clear rules about when to stop and go.