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 possible answer choices. Test questions come from the Idaho Commercial Driver’s 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. The Individual Vehicle Distance Record (IVDR) does not need to include which of the following?

Explanation
An Individual Vehicle Distance Record (IVDR) must include information about the distance traveled by a vehicle and the amount of fuel purchased. The required distance information includes the origin and destination points of the trip and the Vehicle Identification Number.

9. Air brakes use ____ to function.

Explanation
The brakes in an air brake system use compressed air to function properly.

10. Air tank drains should:

Explanation
In an air brake system, air tank drains are used to remove water and compressor oil from the air tanks. When operating a drain, be sure to drain the tank completely.

11. An example of required emergency equipment is:

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.

12. What does blocking cargo do?

Explanation
Blocking and bracing are used to prevent cargo from shifting in transit.

13. Which of the following determines your blood alcohol concentration (BAC)?

Explanation
The main factors that determine a person's blood alcohol concentration (BAC) are how much alcohol has been consumed, how quickly it was consumed, and the person's body weight.

14. Which of the following is not an example of a distracted person who should concern motorists?

Explanation
You should be cautious when you are near people who are not paying attention to the road. Drivers and pedestrians who are talking to someone may be distracted by the conversation and not fully paying attention to the road. Workers on or near the road may not be paying attention to traffic because they are focused on their work, and can themselves also be a distraction to drivers.
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