Knowledge Test Class B

This license is required for driving a single vehicle with a GVWR of more than 26,001 pounds, and a trailer not to exceed 10,000 pounds gross vehicle weight rating, or a vehicle designed to transport 24 or more people (including the.. Read More

This license is required for driving a single vehicle with a GVWR of more than 26,001 pounds, and a trailer not to exceed 10,000 pounds gross vehicle weight rating, or a vehicle designed to transport 24 or more people (including the driver). To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has three or four possible answer choices. Test questions come from the North Carolina Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Pre-Trip Vehicle Inspection Test, Basic Vehicle Control Skills Test and On-Road Driving.. Endorsements that may be used with a Class B CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question
Passing Score

8. Cargo with a high center of gravity:

Explanation
Cargo with a high center of gravity makes a vehicle more likely to tip over than cargo with a low center of gravity. For this reason, it is important that the weight of cargo be distributed as low as possible.

9. When traveling down a hill:

Explanation
When a vehicle is traveling on a downward slope, the force of gravity will cause its speed to increase.

10. When you leave your vehicle, you should:

Explanation
Always apply the parking brake when leaving your vehicle.

11. What kind of force must emergency brakes use?

Explanation
Because air pressure can eventually leak away, the emergency brakes in an air brake system must be held on by mechanical force.

12. Federal and state laws require:

Explanation
Commercial drivers are required by federal and state laws to inspect their vehicles before every trip. Regular inspections can help drivers identify issues before they become dangerous and costly.

13. A CMV should:

Explanation
All commercial motor vehicles are required to be equipped with the proper emergency equipment. This may include spare electrical fuses; three red reflective triangles, six fuses, or three liquid burning flares; and at least one properly charged and rated fire extinguisher.

14. If your wheels being to spin when accelerating on a poor traction surface, you should:

Explanation
If your drive wheels begin to spin while accelerating on a surface with poor traction, you should remove your foot from the accelerator.
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