CDL General Knowledge Practice Test

Question 1

What is the minimum following distance recommended for a commercial motor vehicle under normal conditions at highway speeds?

Accepted Answer

One second for every 10 feet of vehicle length

Answer

For speeds above 40 mph, CMV drivers should maintain at least one second of following distance per 10 feet of vehicle length. For a 60-foot vehicle at highway speed, that's at least 6 seconds. In adverse conditions (rain, snow, night), this should be doubled.

Question 2

Under FMCSA regulations, a CMV driver may drive a maximum of how many hours after 10 consecutive hours off duty (property-carrying vehicles)?

Accepted Answer

11 hours

Answer

Under the FMCSA Hours of Service rules for property-carrying drivers, a driver may drive a maximum of 11 hours after taking 10 consecutive hours off duty. Additionally, the driver cannot drive beyond the 14th hour after coming on duty, regardless of how many hours were actually driven.

Question 3

What does a diamond-shaped sign with a yellow background typically indicate?

Accepted Answer

A warning about upcoming road conditions

Answer

Diamond-shaped signs with yellow backgrounds are warning signs in the US highway sign system. They alert drivers to upcoming conditions that may require speed adjustments or extra caution, such as curves, intersections, pedestrian crossings, or construction zones.

Question 4

When are you required to inspect your cargo during a trip?

Accepted Answer

Within 50 miles after starting, then every 3 hours or 150 miles

Answer

FMCSA regulations require cargo inspections within the first 50 miles after loading, and then at every 3 hours or 150 miles of driving, whichever comes first. Drivers must also inspect cargo after any change in duty status. This applies to loads that could shift or become unsecured.

Question 5

What is the primary reason large trucks take longer to stop than cars at the same speed?

Accepted Answer

Greater mass means more kinetic energy that must be overcome by braking

Answer

The primary reason is the much greater mass (kinetic energy) of a loaded truck. A fully loaded semi can weigh up to 80,000 lbs compared to ~4,000 lbs for a car — 20 times more mass. Kinetic energy increases with the square of speed AND linearly with mass, so stopping distance is dramatically greater.

CDL Practice Test

CDL Practice Test

CDL General Knowledge Practice Test