ELDT Speed and Space Management 2 — Questions and Answers
Question 1: What is the recommended following distance for a heavy vehicle traveling under 40 mph?
- 1 second for every 10 feet of vehicle length (Correct answer)
- 2 seconds regardless of length
- 1 second for the entire vehicle
- 4 seconds total
Correct answer: 1 second for every 10 feet of vehicle length
Below 40 mph, allow one second of following distance for each 10 feet of vehicle length.
Question 2: When traveling over 40 mph, how should a driver adjust the following-distance formula?
- Add one second to the low-speed count (Correct answer)
- Cut the count in half
- Use a flat 2 seconds
- Ignore vehicle length entirely
Correct answer: Add one second to the low-speed count
Over 40 mph you add one additional second to the length-based following distance.
Question 3: Why do heavy vehicles need more following distance than cars?
- They take longer to stop (Correct answer)
- They accelerate faster
- They have better brakes
- They are shorter
Correct answer: They take longer to stop
Their greater weight and length mean longer stopping distances than passenger cars.
Question 4: What is 'total stopping distance' composed of?
- Perception, reaction, and braking distance (Correct answer)
- Only braking distance
- Reaction and turning distance
- Perception distance alone
Correct answer: Perception, reaction, and braking distance
Total stopping distance = perception distance + reaction distance + braking distance.
Question 5: How does empty trailer weight affect braking?
- Empty trucks can take longer to stop due to less traction (Correct answer)
- Empty trucks always stop faster
- Weight has no effect on braking
- Empty trailers cannot use brakes
Correct answer: Empty trucks can take longer to stop due to less traction
Empty trucks have less traction, so brakes can lock up and stopping can actually take longer.
Question 6: At about what speed does stopping distance roughly quadruple compared to half that speed?
- Doubling speed multiplies braking distance by about four (Correct answer)
- Doubling speed doubles braking distance
- Speed has no effect on braking distance
- Braking distance decreases with speed
Correct answer: Doubling speed multiplies braking distance by about four
When you double your speed, braking distance increases about four times.
Question 7: What should you do when following distance is compromised by a tailgater behind you?
- Increase your following distance in front (Correct answer)
- Brake hard to warn them
- Speed up sharply
- Change lanes without signaling
Correct answer: Increase your following distance in front
Open up more space ahead so you can brake gradually and give the tailgater room.
ELDT Speed and Space Management 2
What is the recommended following distance for a heavy vehicle traveling under 40 mph?