Which of these statements is true about large trucks?
- They take longer to stop than passenger vehicles. ✓
- They all have air brakes that allow them to stop quickly.
- They are more maneuverable than passenger vehicles.
Answer: A. They take longer to stop than passenger vehicles.
Large trucks take longer to stop than passenger vehicles.
Why this is the answer
The handbook says plainly that large vehicles take much longer to stop than smaller vehicles going the same speed. It also explains why for tractor trailers: air brakes send braking power from the tractor back to the trailer, and that delay can add many feet to the stopping distance. So the extra stopping room isn't a guess, it comes from how those rigs are built. Give them space and don't cut in front of them.
Why the other answers are wrong
- B. They all have air brakes that allow them to stop quickly. — Air brakes do not make trucks stop quickly; the handbook says the delay in transmitting brake power to the trailer can add many feet to the stopping distance.
- C. They are more maneuverable than passenger vehicles. — The handbook states the opposite, that large vehicles are not as maneuverable as cars and often need to swing wide to turn.
Remember it
Think of a truck's stop as a stretched-out event: air has to travel back to the trailer before the brakes bite, so leave extra room.