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The CDL general knowledge test is required to be taken by all CDL applicants. The Iowa CDL test consists of 50 questions. To pass, you must correctly answer at least 40 questions (80%). The general knowledge test covers the contents of the Iowa CDL Manual. All CDL applicants (Class A, B and C) must study the following sections: Driving Safely, Transporting Cargo Safely, Air Brakes (if you plan to operate vehicles equipped with air brakes), Vehicle Inspection Test, Basic Control Skills Test, Road Test. In addition, the Class A CDL test will include questions based on the Combination Vehicles section. Take this CDL practice test now to prepare for the actual IA general knowledge test! To get your CDL, you must pass both the knowledge and skills tests. CDL knowledge tests include: General Knowledge, Passenger Transport, Air Brakes, Combination Vehicles, Hazardous Materials, Tanker Vehicles, Doubles/Triples, School Bus, Firefighter. Depending on what class of license (A, B or C) and endorsements you need, you must take one or more knowledge tests. A special endorsement is also required to drive certain types of vehicles. The following endorsements may be used with a Class A, B or C CDL: HazMat (H), Tank Vehicles (N), Tank Vehicles Transporting Hazardous Materials (X) and Passenger Transport (P). The School Bus endorsement (S) is only available for Class A or B CDL, and the Doubles/Triples endorsement (T) is only available for Class A driver's licenses.
1. What should you do at an accident scene, among other things, to help prevent another accident?
Put on your 4-way emergency flashers.
If you are stopping to help, park in the area immediately around the accident.
Stay in your vehicle and file an accident report.
2. What is a pull up when referring to truck driving?
When a driver stops and pulls forward to get a better position.
A specific maneuver used to decelerate smoothly in the exit lane.
A driving maneuver used to pull your vehicle over to the side of the road and stop.
3. Too much weight on the steering axle can cause:
better handling.
poor traction.
hard steering and damage to the steering axle and tires.
4. Retarders:
reduce braking distance.
improve gas mileage.
help slow a vehicle, reducing the need for using brakes.
5. It is safer to drive over (rather than to avoid) which of the following?
Paper and cloth sacks
Cardboard boxes
None of the above.
6. Hydroplaning is more likely if:
tire pressure is low.
tire tread is worn.
All of the above.
7. Empty trucks:
require greater stopping distances.
are higher than loaded trucks.
All of the above.
8. Which of these can cause your vehicle to skid?
Over steering
Braking any harder than necessary on slippery roads
All of the above.
9. Using of a hand-held mobile device while driving is:
not encouraged.
10. When you see a hazard that will require slowing down, you should:
warn the drivers behind by flashing your brake lights.
alert the drivers behind by pointing and sounding your horn.
immediately come to a compolete stop.
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Number of questions: 50
Correct answers to pass:40
Passing score:80%
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