How to Determine the Distance to the Rear Vehicle Using the Rearview Mirror?
2 Answers
To determine the distance to the rear vehicle using the rearview mirror: 1. When the rear vehicle is at the center of the left rearview mirror, the distance is approximately 15 to 20 meters; 2. When half of the rear vehicle's body is visible in the left rearview mirror, the distance is about 2 meters; 3. When the rear vehicle occupies a quarter of the right rearview mirror's area, the distance is approximately 24 meters; 4. If only half of the rear vehicle's body is visible in the right rearview mirror, the distance is about 1 meter. These methods can help estimate the following distance, but since blind spots cannot be completely eliminated, it's important to not only check the rearview mirror but also glance out the side window to ensure no vehicles are present before turning, ensuring a safe maneuver.
Judging the distance of the following car using the rearview mirror is quite simple—it mainly involves observing the size and position of the car in the mirror. Here's how I do it: If the following car appears very small, occupying only a small portion of the mirror, it means the distance is at least several dozen meters away, which is quite safe. If the car grows larger and nearly fills the mirror, I need to be cautious as it might be very close, potentially catching up to me in just a few seconds. When driving at high speeds, I use fixed reference points like roadside trees to calculate the time gap—I count to three seconds after the following car passes the tree to ensure safety. If the mirror isn’t adjusted properly or there’s a blind spot, I turn my head to double-check. During rainy days or at night when visibility is poor, I’m extra careful and reduce speed to avoid misjudgment. With practice, I’ve developed a natural sense of distance changes, which helps with safe lane changes and braking. After years of driving, this habit has saved me multiple times.
