California DMV Permit Test (Class C)Safe Driving PracticesMedium
You are driving in heavy city traffic, and the vehicle ahead stops suddenly. To avoid a collision, how much following distance should you generally maintain?
- AA minimum of three seconds behind the vehicle ahead.
- BEnough distance to see the vehicle's tires touching the pavement.
- CNo more than two seconds, to prevent other drivers from cutting in.
- DAt least one car length for every 10 mph of speed.
Show answer & explanationAnswer & explanation
Correct answer: A. A minimum of three seconds behind the vehicle ahead.
The 'three-second rule' is a widely recommended guideline for maintaining a safe following distance under good conditions. It provides enough time to react to sudden stops and is easily adaptable to different speeds.
Why the other options are wrong
- B. While seeing their tires is a good immediate indicator for stopping distance, the three-second rule is for dynamic following distance.
- C. Two seconds is often insufficient, especially in heavy traffic where sudden stops are common; prioritizing gap protection over safety is dangerous.
- D. This is an older, less precise rule. The time-based rule is generally preferred.
Three-Second Rule
The 'three-second rule' is a method to estimate a safe following distance by counting three seconds from when the vehicle ahead passes a fixed object until your vehicle passes the same object.
- Provides a safe stopping distance.
- Adjustable for speed and conditions (increase for adverse conditions).
- Helps avoid rear-end collisions.
- Easy to calculate while driving.
Memory trick: Three seconds count, for safety's amount.