Final answer:
The claim about barricades being the most common device to alert drivers in work zones is false; signs, cones, barrels, and barriers are more commonly used. A wire touching a car at tollbooths is not standard practice. Traffic signals are installed at intersections mainly due to high accident rates, pedestrian risk, and to control vehicle speeds.
Step-by-step explanation:
The statement that the most common devices used to alert drivers of unusual or potentially dangerous conditions in highway and street work zones are barricades is false. While barricades are indeed used for such purposes, the most common devices are typically signs, cones, barrels, and barriers. These act as visual cues to notify drivers of changes in driving conditions, ensuring both worker and driver safety.
Tollbooth stations might have a variety of mechanisms for different functions, such as sensors or wires to detect the approach of vehicles, but the specific scenario described with a wire touching a car is not standard practice and is unrelated to the most common devices for alerting drivers in work zones.
High accident rates at intersections, risks to pedestrians, and vehicle speeds are significant considerations that often lead to the installation of a traffic signal. A recent model cause-and-effect paragraph about the reasons for installing a traffic signal at an intersection highlighted the connection between high accident rates, the safety of pedestrians and motorists, and the regulation of vehicle speed as compelling reasons for such an installation.