CDL · Air brakes
Air brakes contain three separate braking systems. Two of them are the service brake and the parking brake. What is the third one?
Correct answer: The emergency brake.
Answer options
- AThe emergency brake Correct
- BThe engine brake
- CThe drum brake
Why
Air brakes combine a service brake for normal stops, a parking brake to hold the vehicle in place, and an emergency brake that uses parts of both of those systems to stop the vehicle if the brakes fail. A drum brake is a type of brake hardware and an engine brake is a separate retarder, so neither is one of the three systems.
About this question
Topic: Air brakes License: CDL
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Where it applies: Asked in every state.
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This question is part of CDL Practice Exam (50 questions). Take the full set and check your score.
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