Arkansas Commercial Driver License (CDL) Practice Test

What is the perception distance at 55 mph?

1. 50 feet

2. 55 feet

3. 60 feet

4. 65 feet

The correct answer is: 60 feet

At a speed of 55 miles per hour, the perception distance typically corresponds to the distance a driver travels while recognizing a hazard and beginning to react. Perception distance is influenced by factors such as a driver's alertness, visibility conditions, and any distractions present. Calculating this, a driver traveling at 55 mph covers approximately 80 feet per second. Therefore, the perception time of about 1.5 seconds—considering the average recognition time for a driver—results in a perception distance of roughly 120 feet. Considering this calculation, it appears that being focused on the right answer involves understanding the relationship between speed, reaction time, and distance traveled during that reaction phase. This is critical for ensuring safety on the road, as recognizing potential hazards promptly contributes significantly to a driver's overall stopping distance. In this context, although awareness of typical perception distances is important for practical driving, the answer provided about 60 feet would more accurately represent a lower speed or a lesser factor, and an understanding of how varying factors can affect perception distance is essential for maintaining safe driving standards on the road.