Arkansas Commercial Driver License (CDL) Practice Test

What is the reaction distance at 55 mph?

1. 1.5 seconds

2. 1 second

3. 60 feet

4. 75 feet

The correct answer is: 60 feet

The correct answer reflects the typical reaction distance for a vehicle traveling at 55 mph, which is approximately 60 feet. Reaction distance is the distance your vehicle travels from the moment you perceive a hazard to the moment you begin to apply the brakes. In general, at higher speeds, vehicles cover more ground in the time it takes for the driver to react. For instance, at 55 mph, it takes about 1 second to recognize a hazard and begin to respond, during which time the vehicle travels approximately 60 feet. This is calculated based on the understanding that, at 55 miles per hour, a vehicle is moving at about 80 feet per second. Thus, the distance covered in 1 second of reaction time would indeed be around 60 feet. Understanding this concept is crucial for any commercial driver, as knowing reaction distances can help maintain safe following distances and avoid collisions.