**what g-force acts on you**in a car crash. Everybody knows that automobile collisions are very dangerous, but what is the physics behind it ? Can we predict the consequences of a car crash ? The answer is yes and no. The damages to health in an accident can be dangerous, and they depend on many factors, e.g. :

**car speed**– the higher the speed, the more energy you have,**seat belt**– we will show that seat belts can save your life,**airbag**– another thing that can protect your life,**car type**– you are more likely to survive a car crash if you’re in bigger car,**obstacle**– the situation is different when we hit a bush or a tree.

We ca n’t precisely calculate whether we survive or not, but we can make some estimations to be aware of crash consequences. What happens if you drive with the travel rapidly of 20 miles per hour and you on the spur of the moment stop ? **Just imagine that a 7 tonne block lies on your chest**. Yes, it ‘s about the lapp. recently, the **NHTSA** ( National Highway Traffic Safety Administration ) performed many crash tests with dummies. Basing on these tests, we can make some approximations at what travel rapidly you can die in a cable car crash .

In this cable car crash calculator, we explain how to calculate the impact effect in cable car crashes and how seat belts and airbags can protect you. You ‘ll find out that they can drastically increase your chances to survive. With the following text, you can learn about the power of affect definition and impingement power equality .

You do not need to be the driver to know that **you can’t stop the car immediately**. The sum stopping distance depends on the perception time of a driver and the brake outdistance. If you want to find out how far you will travel before your cable car stops, check out our stopping distance calculator now !

Bạn đang đọc: Impact Force Calculator

Table of Contents

## Force of impact definition – impact force equation

force of impact is the total military unit exerted on an object during a collision. To derive the shock force equation, you can consider the law of conservation of energy. At the beginning, a moving object possesses kinetic energy that **reduces to zero** after the collision ( object stops ). To fulfill the conservation law, the change of kinetic energy must be compensated by the study done by the impact power. We express it with the under impingement power equation

`F = m * v² / (2 * d)`

,

where

`F`

is the average impact force,`m`

is the mass of an object,`v`

is the initial speed of an object,`d`

is the distance traveled during collision.

What may at first surprise you, is that extending the distance moved during the collision reduces the average impact force. It should be easier to understand if we rewrite the above impact force recipe in the alternative version using the time of collision `t`

alternatively of the distance `d`

:

`F = v * m / t`

This is a special case of nerve impulse and momentum recipe. now, you can see that extending the fourth dimension of the collision will decrease the average impact military unit. Let ‘s consider two situations where you jump from a specific height. In the first gear encase, you jump to the earth and in the second, on a trampoline. Because the surface of a trampoline is more stretchable, it extends the time of the collision. You can feel that your legs are subjected to a lesser average impingement pull .

This case is analogical to car crashes. **Cars are made to collapse upon impact** extending the time of the collision and lessening the impact force. That ‘s why they ca n’t be besides durable.

Xem thêm: Wikipedia

## How to calculate impact force? G-force in car crashes

Impact impel formula we used above trace an ideal collision between two objects. In the actual situation of a car crash, **the profile of force during the accident can be more extensive** – for example, you should take into report that car collapses and that a human is not a orient multitude but a complex body. however, you can still make some estimations of impingement force during a car clang .

Take a spirit at the picture below. At inaugural, the driver sits in the car that is in constant motion with a focal ratio `v`

. then, a car hits the tree and immediately stops. **The driver flies forward due to the inertial force** until he is stopped abruptly by the impact on the steering column or windshield. The stopping distance is identical short because none of the collide objects ( including body and, for example, windshield ) are contractible adequate. We can estimate it to be approximately 4 centimeter ( you can change it in the boost mode of this impact force calculator ) .

How to calculate the impingement force acting on a driver with the mass of 70 kg ? Let ‘s use our car crash calculator ! If the initial car speed is 30 kilometers per hour and the distance of collision is 4 centimeter, then the impact military unit is about 60 kN. **It is an equivalence of 6 tons!** It is merely as if person put a large rock stuff on your thorax. On the other hand, the end fourth dimension is only 9.6 master of science which means that to reduce the driver ‘s speed from 30 km/h to zero, the driver has to decelerate about 89 times faster than is Earth ‘s standard gravity g .

## How can seat belts and airbags protect you?

The chief job of seat belts and airbags is the same. They both **extend the distance of the collision**. Assume that we ‘ve got the lapp situation as ahead. The 70 kilogram driver drives a car with a speed of 30 km/h, but this time, he is hard held in buttocks knock harness. The seat belt out will stretch a short moment when the impact wedge is applied. We can say that it can expand by about 20 curium ( you can change it in the advanced mode of this impact force calculator ) .

Again, after using the car crash calculator, you can obtain the average impact pull of about 2.5 kN that is about 25 times smaller than without the seat belt. It corresponds to the system of weights of 1.24 tons. The stop time lengthens to 48 megabyte, and now, the driver decelerates “ entirely ” 18 times faster than with Earth ‘s standard gravity thousand .

To sum up, the seat belt is designed to stop your body from hitting hard things in the car and **reduce the impact force you experience by spreading it out over a time**. The seat knock could occasionally contribute to severe home injury or even death if the impingement power is besides adult. however, present seat belts have a mechanism that breaks them at a predefined level of tension. normally, there are still airbags placed in front of the driver in order to increase their base hit .

We have made an model with the driver, but **any person** in the vehicle is subjected to these dangers. If you crash with a heavy truck, it does n’t matter whether you sit behind the roulette wheel or at the back induct of the car. even in the low-speed collisions, **the impact force which stops your body is in the range of tonnes**. You simply wo n’t be able to hold on and prevent injury without buttoned seat belts. furthermore, if you sit at the spinal column of the car and you are n’t constrained by a seat belt, you will fly straight ahead like a boulder of respective tonnes. **You will not only hurt yourself but also your friend in front of you!**

Xem thêm: Meineke Car Care Center

## At what speed can you die in a car crash?

This is one of the questions that **don’t have one unambiguous answer**. The heavier the cable car is, the hard it is to stop it, and the impingement military unit is smaller. On the other pass, the fomite will immediately stop if it hits a wall of a house, but the situation will be different if it hits another cable car that participates in dealings. consequently, we must take into report many unlike factors .

In general, **high speed doesn’t produce harmful injuries**. What is dangerous for a homo is the high acceleration or deceleration given at a specific measure of clock time. The National Highway Traffic Safety Administration ( NHTSA ) is an representation that conducts traffic condom inquiry around the world. It describes its mission as Save lives, prevent injuries, reduce vehicle-related crashes. The NHTSA states that “ the maximum breast acceleration **shall not exceed 60 g for time periods longer than 3 milliseconds** “ ( generator : NHTSA ) .

With our car crash calculator, you have learned that the accelerations during car crashes can be a draw higher than 60 gram without tied seat belts. **So use them and save your life!** NHTSA states that seat belts reduce death rates by 45 % and reduce the gamble of injury by 50 % .