Driving at high speed speed 110 per hour, the vehicle in front of me suddenly braked sharply, can I brake at a distance of sixty meters?
Many people's brains are, can be avoided, ah, now the braking distance of the car speed of 100 per hour is not within 40 meters? You can brake within 110 meters, and you can definitely brake within 60 meters. But that's not how it's calculated, because you also have to count the driver's reaction time and the response time of the braking system.
In addition, it is difficult to generalize in several situations, so let's see if the most ideal situation and the least ideal situation can avoid rear-end collisions.
First, the most ideal situation
1. The driver perceives the brakes in front of the car when he sees the brake lights in front of him, and then brakes immediately
2, the driver's reaction speed, generally speaking, the driver's reaction time is between 0.4 seconds and 1 second, we calculate according to 0.4 seconds.
3. The brake system responds quickly and achieves the expected braking effect in about 0.5 seconds.
(Industry standard: In emergency braking, the time elapsed from the start of the actuation control device to the braking force on the most unfavorable axle to the corresponding specified braking efficiency should not exceed 0.6s.) )
4, the braking distance of the vehicle, is the current mainstream level, not the new car state, in about 40 meters or so can be braked from 100 per hour is good, then in the case of speed 110 per hour, its braking distance should be about 49 meters. Let's assume that the braking distance between the two is about the same.
And 110 km / h ≈ 30.56 m / s, if according to this calculation, from the driver's reaction to the brakes in front of the car, and then to the car brake effect, 0.9 seconds have passed, your car forward 27 meters, and the braking distance needs 49 meters, you need at least 76 meters to brake. Although the front car will continue to move forward after stepping on the brakes, because you brake later than the other party, your relative distance is actually shortened, and your relative distance is not enough, so it will still rear-end.
Then, other situations do not need to be calculated, and the ironclad is bound to occur, but the weight of the result.
Such an account tells us why there is often a 50-meter ranging sign on the highway, reminding you to keep a distance from the car in front, because the high-speed speed is fast, the braking distance is long, and it is very important to maintain a safe distance, do not think that your car can brake at a speed of 100 per hour, more than 30 meters can brake, so the 50-meter distance is enough to drive at high speed. The brake results tested are basically in the new car state, and they are greatly affected by the road weather. Counting the driver's reaction time, so for your safety, keep at least 150 meters away at high speeds and don't joke about your life.