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 State of Delaware 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

1. Which of the following is not acceptable emergency equipment?

Explanation
During the vehicle inspection test, you will need to show emergency equipment, including spare electrical fuses; three red reflective triangles, six fuses, or three liquid burning flares; and a properly charged and rated fire extinguisher.

2. When inspecting your brakes, a slack adjuster should move ____ from where it is attached to the push rod.

Explanation
Check each slack adjuster after setting wheel chocks and disengaging the parking brake. Pull the slack adjusters to make sure they do not move more than about one inch from where the push rod is attached. If they move more than one inch, they may be out of adjustment and will need to be fixed.

3. Applying the brake pedal causes air pressure to activate an electric switch and:

Explanation
In a vehicle with air brakes, the brake lights are activated when the brake pedal is pushed and air pressure moves an electric switch. With the application of air pressure, the switch will then turn on the brake lights.

4. A vehicle that is smaller than your vehicle:

Explanation
In general, a smaller vehicle will be able to come to a complete stop faster than a larger vehicle. Keep this in mind when determining your following distance.

5. If unable to tell if the road is becoming icy and slippery, a driver:

Explanation
If you think the road surface may be becoming icy but you are not certain, you can open your window and feel the front of the side mirror, mirror support, or antenna. If ice has formed on any of these items, the road is likely becoming icy as well.

6. Air tank drains:

Explanation
Compressed air in an air brake system usually has a certain amount of water and oil in it. This can harm the system if allowed to accumulate. Air tanks have drain valves to aid in removing water and oil from the compressed air.

7. Dry bulk tanks require special care because:

Explanation
Driving with a dry bulk tank requires special care, both because dry bulk tanks have high centers of gravity and because their loads often shift in transit. Be especially careful when taking turns and curves while operating such a vehicle.
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