CDL · Air brakes
Why do air brakes take longer to work than hydraulic brakes?
Correct answer: Air takes longer than hydraulic fluid to move through the lines.
Answer options
- AAir brakes are built with a different type of brake drum
- BAir takes longer than hydraulic fluid to move through the lines Correct
- CAir is constantly leaking out through the line fittings
Why
When you press the pedal, compressed air has to travel through the lines before the brakes engage, which takes a little longer than with hydraulic fluid. This short delay, called brake lag, adds distance to every stop in an air-brake vehicle.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
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This question is part of Checking and Using Air Brakes (15 questions). Take the full set and check your score.
Practice Checking and Using Air BrakesMore questions from Checking and Using Air Brakes
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