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 two, three or four possible answer choices. Test questions come from the Minnesota Commercial Driver’s 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. Placards should be used:

Explanation
Placards must be placed on the outside of vehicles carrying hazardous materials. They identify the specific class or classes of materials being carried and warn others of relevant hazards.

2. Drivers often tailgate trucks in bad weather.

Explanation
It is common for automobile drivers to follow too closely behind large trucks in bad weather, especially when it is difficult to see down the road. Safely respond to the tailgater instead of reacting by increasing your speed.

3. Which part of the truck is the air compressor connected to?

Explanation
In an air brake system, the air compressor is connected to the engine through gears or a v-belt.

4. If driving so slowly that you could impede other drivers, you should:

Explanation
If you must drive so slowly that you will impede the flow of traffic, you should turn on your four-way flashers to alert drivers behind you (as long as local laws allow the use of flashers).

5. Air brakes use ____ to function.

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

6. Which of the following can help you determine when to upshift?

Explanation
There are two indicators that determine when you need to shift into a higher gear. One indicator is the engine speed (rpm). You should read your vehicle's manual to learn its rpm range and shift up when you reach the top of that range. The other indicator is road speed (mph). You should learn which speeds each gear can accommodate, then keep an eye on the speedometer and shift up as needed.

7. Convex mirrors:

Explanation
Many large vehicles have curved, convex mirrors. Convex mirrors allow drivers to see a wider area than flat mirrors. However, they also make objects seem smaller and farther away than they really are.
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