CDL · Air brakes
Besides the service brake and the parking brake, what is the third braking system that makes up air brakes?
Correct answer: The emergency brake.
Answer options
- AThe emergency brake Correct
- BThe S-cam brake
- CThe foot brake
Why
Air brakes are really three systems in one: the service brake for everyday slowing and stopping, the parking brake that keeps a parked vehicle from rolling, and the emergency brake, which draws on parts of the other two to stop the vehicle if the brake system fails.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of How Air Brakes Work (18 questions). Take the full set and check your score.
Practice How Air Brakes WorkMore questions from How Air Brakes Work
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