CDL · Night and weather
If you must drive through fog, which lights should you use, and why?
Correct answer: Low beams and fog lights, because high beams reflect off the fog.
Answer options
- AHigh beams, because they reach farther into the fog than low beams
- BLow beams and fog lights, because high beams reflect off the fog Correct
- CParking lights alone, because any headlights create glare in fog
- DNo lights during the day, because fog limits vision only at night
Why
Fog is made of tiny water droplets that throw the strong light of high beams back at you as glare, so you actually see less. Low beams and fog lights are aimed lower and cause less glare, and using them even in daytime also helps other drivers notice your vehicle.
About this question
Topic: Night and weather License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of Night and Fog Driving (14 questions). Take the full set and check your score.
Practice Night and Fog DrivingMore questions from Night and Fog Driving
- You are driving a commercial vehicle on the highway when the fog becomes so dense that you can see only a short distance ahead. What is the safest decision?
- What is the proper rule for using high beams?
- You are driving at night and dim to low beams for an oncoming vehicle. What is the correct response?
- At night, you switch to low beams because a vehicle is coming toward you. How should you adjust your driving?
- Which statement about using your headlights at night is accurate?
- You are driving at night, and the bright headlights of an oncoming vehicle are glaring in your eyes. Where should you look until that vehicle has passed?
- Which of these practices makes night driving safer?
- You have been using high beams and now switch to low beams. What should you do about your speed?
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