CDT Traffic Laws & Regulations 3 — Questions and Answers
Question 1: Under the Uniform Vehicle Code, what does a flashing yellow traffic signal indicate to a driver?
- Stop and wait for a green signal
- Proceed with caution (Correct answer)
- The signal is about to turn red
- Yield to pedestrians only
Correct answer: Proceed with caution
A flashing yellow signal warns drivers to slow down and proceed through the intersection with caution.
Question 2: A CDT candidate is reviewing a scenario where a driver fails to dim high beams when meeting oncoming traffic. Under most state laws, high beams must be dimmed within how many feet of an oncoming vehicle?
- 100 feet
- 200 feet
- 500 feet (Correct answer)
- 1,000 feet
Correct answer: 500 feet
Most state laws require drivers to switch from high beams to low beams within 500 feet of an oncoming vehicle to prevent blinding the other driver.
Question 3: Which of the following actions is REQUIRED when approaching a stationary emergency vehicle with flashing lights on a multi-lane highway under Move Over laws?
- Sound the horn to alert first responders
- Move over one lane away from the vehicle if safely possible, or slow down significantly (Correct answer)
- Continue at posted speed but turn on hazard lights
- Stop immediately regardless of traffic conditions
Correct answer: Move over one lane away from the vehicle if safely possible, or slow down significantly
All 50 states have Move Over laws requiring drivers to vacate the adjacent lane or reduce speed substantially when passing stationary emergency vehicles.
Question 4: When teaching lane changes on a freeway, a CDT instructor should emphasize that a driver must signal before changing lanes for at least how many seconds in most states?
- 1 second
- 3 seconds (Correct answer)
- 5 seconds
- 10 seconds
Correct answer: 3 seconds
Most state vehicle codes require a signal to be activated at least 3 seconds (or 100 feet on surface streets) before initiating a lane change.
Question 5: Under the FMCSA regulations, what is the maximum speed a CMV driver may operate a vehicle while transporting hazardous materials placarded Class 1 explosives on a two-lane road?
- The posted speed limit applies with no additional restriction
- 55 mph regardless of posted limit (Correct answer)
- 45 mph regardless of posted limit
- 35 mph regardless of posted limit
Correct answer: 55 mph regardless of posted limit
FMCSA regulations (49 CFR 397.15) limit vehicles carrying explosives to a maximum of 55 mph on public roads regardless of the posted limit.
Question 6: A CDT student asks about the purpose of white edge lines (fog lines) painted on the right side of a roadway. What is their primary function?
- Mark the boundary of a bicycle lane
- Define the right edge of the travel lane to guide drivers, especially in low visibility (Correct answer)
- Indicate a no-passing zone
- Show where school bus stops are located
Correct answer: Define the right edge of the travel lane to guide drivers, especially in low visibility
White edge lines (also called fog lines) delineate the right boundary of the roadway, helping drivers maintain lane position in fog, rain, or darkness.
Question 7: Which of the following pavement markings indicates a no-passing zone to drivers on a two-lane road?
- Single broken yellow center line
- Double solid yellow center lines (Correct answer)
- Single solid white edge line
- Broken white center line
Correct answer: Double solid yellow center lines
Double solid yellow center lines prohibit passing in either direction and mark no-passing zones on two-lane roads.
CDT Traffic Laws & Regulations 3
Under the Uniform Vehicle Code, what does a flashing yellow traffic signal indicate to a driver?