CDL · CDL general knowledge
What is true about how brakes stop a vehicle?
Correct answer: A heavier or faster vehicle forces its brakes to absorb more heat when stopping.
Answer options
- AAt high speed, the brake drums give off their heat almost immediately.
- BBrakes become more effective at stopping the vehicle once they get very hot.
- CA heavier or faster vehicle forces its brakes to absorb more heat when stopping. Correct
Why
Brakes slow a vehicle by turning its motion into heat through friction, so extra weight or speed means extra heat for them to absorb. That heat does not add stopping power; overheated brakes weaken and can fade, so brake early and keep plenty of space ahead.
About this question
Topic: CDL general knowledge License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
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This question is part of Mountain Grades and Brake Fade (16 questions). Take the full set and check your score.
Practice Mountain Grades and Brake FadeMore questions from Mountain Grades and Brake Fade
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