CDL · Air brakes
When a vehicle has air brakes, what is the brake pedal's job?
Correct answer: It regulates how much air pressure reaches the brakes.
Answer options
- AIt regulates how much air pressure reaches the brakes Correct
- BIt determines how fast the air compressor runs
- CIt must stay pressed halfway down during normal driving
Why
The brake pedal, also called the foot valve or treadle valve, controls the air sent to the brakes: pushing it harder applies more air pressure, and letting up releases air and eases the brakes off. It has no effect on how fast the compressor runs, and you should not rest your foot on it during normal driving.
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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