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 four possible answer choices. Test questions come from the 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. An air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately ____ to come to a complete stop.

Explanation
A vehicle's total stopping distance is made up of perception distance, reaction distance, brake lag distance, and braking distance. With all of these factors included, an air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately 450 feet to come to a complete stop.

2. What should you do if the brake pedal does not build up pressure?

Explanation
If you lose pressure in a hydraulic brake system, one appropriate response is to shift down into a lower gear. This will help slow the vehicle.

3. In a convex mirror, objects seem ____ than they actually are.

Explanation
A convex mirror makes objects seem smaller and farther away than they actually are.

4. 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.

5. When passing another vehicle, you should:

Explanation
Whenever you pass another driver, bicyclist, or pedestrian, you should assume as a precaution that they do not see you.

6. If a vehicle is equipped with power steering, the hoses should be checked:

Explanation
When inspecting a vehicle that is equipped with power steering, check the hoses, pumps, and fluid level. In particular, you should look for leaks in the hoses.

7. If your truck or trailer catches fire, you should:

Explanation
If there is a fire in your vehicle, the first thing you need to do is leave the road and stop. Park in an open area away from anything that could catch fire, such as plants or other vehicles. Do not pull into a service station.
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