Arkansas Commercial Driver License (CDL) Practice Test

How many seconds of space is needed for a 40 ft vehicle traveling under 40 mph?

1. 3 seconds

2. 4 seconds

3. 5 seconds

4. 6 seconds

The correct answer is: 4 seconds

The correct answer of four seconds is based on the general rule of following distance for heavy vehicles like a 40-foot truck traveling at 40 mph. This rule suggests that drivers maintain a minimum of one second of distance for every ten feet of vehicle length when traveling under normal conditions. In this case, a 40-foot vehicle would require approximately four seconds of following distance. This distance allows for safe reaction time and adequate space for stopping as needed, considering the vehicle's larger size and the longer stopping distance compared to smaller vehicles. While the other choices may represent different timings, they do not account for the specific requirements necessary for maintaining safety and control in a larger vehicle at that speed. Following this guideline helps increase safety for the driver, passengers, and other road users.