Knowledge Test Class A

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question.. Read More

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has three possible answer choices. Test questions come from the Arizona Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination, Doubles and Hazardous Materials. Endorsements that may be used with a Class A CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question
Passing Score

1. A fatigued driver:

Explanation
Fatigued drivers are slower to see or react to hazards than drivers who are not fatigued. Drivers are impaired in their ability to make critical decisions when they are driving drowsy.

2. A ____ allows a driver to gradually apply spring brakes.

Explanation
A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.

3. When driving, mirrors should be used:

Explanation
It is essential that you are aware of what is surrounding your vehicle at all times. You should make a habit of regularly checking your mirrors while driving.

4. When the spring brakes are on, you should never:

Explanation
Never push down the brake pedal while the spring brakes are activated. The combined force of springs and air pressure could damage the brakes.

5. Air storage tanks:

Explanation
In an air brake system, the air storage tanks hold compressed air to be used by the brakes. The number and size of air tanks varies among vehicles.

6. The effects of alcohol are felt:

Explanation
Alcohol impairment can begin with the first drink consumed. It is both illegal and dangerous to operate a motor vehicle while impaired by alcohol.

7. What is brake lag?

Explanation
Because air takes time to flow through the air lines to the brakes, air brakes cannot begin working instantly. There is often a brake lag of at least one-half of a second between the moment the brake pedal is pressed and the moment the brakes begin to work.
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