How to Judge the Distance of the Rear Car Using Rearview Mirrors?
3 Answers
Methods to judge the distance of the rear car using rearview mirrors include: 1. The position of the rear car on the outer side of the rearview mirror indicates a closer distance, while the inner side indicates a farther distance; 2. The larger the size of the rear car in the rearview mirror, the closer the distance, and the smaller the size, the farther the distance; 3. When the internal rearview mirror can see the hood of the rear car but not the grille, the distance is approximately 3 meters, and when the grille of the rear car is visible, the distance is about 8 meters. Car rearview mirrors are important safety components, and their function is to allow the driver to indirectly see the conditions behind, beside, and below the car, thereby expanding the driver's field of vision.
Driving instructors always teach us to judge the distance through the rearview mirrors, but there's actually a trick: On flat roads, observe the size of the following car in the inner rearview mirror. If the following car occupies one-third of your mirror, it's roughly more than ten meters away, and you can still consider changing lanes; if it fills half the mirror, then it's extremely close, and you must not force a lane change. The principle is similar when looking at the side mirrors—as long as the following car is still visible in the mirror, there's usually some distance left. A crucial reminder: always glance at the position of the following car before changing lanes—if it's parallel to your car or even its front exceeds your position, you must not change lanes. Be extra cautious on rainy days and at night when everything in the rearview mirror is blurry, making distance judgment even harder; slow down before changing lanes.
Once when I was driving my best friend on a trip, she asked from the passenger seat if it was safe for the car behind to follow so closely in the rearview mirror. I pointed at the mirror and explained: Look, if the car behind takes up less than half of the mirror, there's roughly a distance of three to four car lengths, which is still a safe distance; if the entire car almost fills up the mirror, then it's definitely way too close. Checking the side mirrors is even simpler—as long as the car is still visible in the mirror and hasn't pulled up beside your car, it means there's some space left. On the highway, especially when changing lanes, it's crucial to take an extra glance at the side rear window to confirm, because rearview mirrors have blind spots. Now I've developed the habit of quickly glancing over my shoulder before changing lanes.
