Examkin

Question

Difficulty: MediumNight Driving and Headlight Usage

A motorist is driving at night on an unlit rural highway at 50 mph50\text{ mph}. The vehicle's low-beam headlights illuminate objects up to 150 feet150\text{ feet} ahead, but at 50 mph50\text{ mph}, the vehicle requires approximately 200 feet200\text{ feet} total stopping distance. Which statement correctly identifies the hazard present in this scenario and the required action under safe driving principles?

  1. The driver is overdriving the headlights and must reduce speed so the total stopping distance does not exceed the illuminated distance ahead.Answer
  2. B
    The driver is legally safe continuing at 50 mph50\text{ mph} as long as the speed does not exceed the posted numerical speed limit.
  3. C
    The driver should activate high-beam headlights continuously, regardless of oncoming traffic or preceding vehicles, to extend visibility past 200 feet200\text{ feet}.
  4. D
    The driver should maintain speed but double the following distance interval behind the illuminated low-beam horizon.

Answer

The driver is overdriving the headlights and must reduce speed so that total stopping distance does not exceed the distance illuminated by the headlights.
When total stopping distance (200 feet200\text{ feet}) exceeds the range of headlight visibility (150 feet150\text{ feet}), the driver is 'overdriving' the headlights. In this situation, any hazard appearing at the edge of the light beam cannot be avoided. The basic speed law requires reducing speed until the stopping distance fits within the illuminated visual field.

Step-by-Step Solution

1
Compare total stopping distance with headlight illumination distance
Total stopping distance (200 feet200\text{ feet}) exceeds low-beam illumination distance (150 feet150\text{ feet}) by 50 feet50\text{ feet}.
If an object appears at the edge of the light beam (150 feet150\text{ feet} away), the vehicle traveling at 50 mph50\text{ mph} cannot stop in time to avoid a collision.
2
Apply the concept of 'overdriving headlights' and the Basic Speed Law
Identify that speed must be reduced until stopping distance is less than or equal to 150 feet150\text{ feet}.
Safe night driving requires that a driver can always bring the vehicle to a complete stop within the visible distance provided by headlights.

Key Concept

Overdriving Headlights and Safe Speed Calibration at Night
Estimated Time:1m 0s
Rate this question

Topics

Night Driving and Headlight Usage

More questions from this topic