Enter the total deformation distance and the spring constant of the collision to determine the impact force of an object, such as a car crash.

## Impact Force Formula

The following formula is typically used to calculate and impact force.

W = 1/2 F_{max} s = 1/2 k s^{2}

- W = work done (J, ft lb)
- F
_{max}= maximum force at the end of the deformation (N, lb_{f}) - s = deformation distance (m, ft)
- k = spring constant

## Impact Force Definition

Impact force is a term used in physics, specifically in mechanics, to describe a force of a short period of time when objects collide. A high force applied to an object in a short amount of time results in a very quick acceleration. This fast acceleration is what cause much of the damage in collisions. Whether that is a car or a persons body part.

If this force as to be applied of a long period of time, the acceleration would be much smaller and the resulting damage would be much less. As a results, things like cars are designed to increase the amount of time the force is applied. In other words, cars are meant to crumple and deform because a slower acceleration, or in the case of a car crash, deceleration, is safer for a human body to endure.

As can be seen by the formula above, the work done is directly proportional to the spring constant and exponentially related to the deformation. For this reason cars are meant to deform as much as possible during crashes.

## How to calculate an impact force?

The following example is a step by step guide on how to calculate the impact force of a collision between two cars.

- First, we must analyze the equation above to determine the missing variables and the correct formula. After re-arranging some variables, we find that the max force = k * s where k is the spring constant and s is the displacement.
- We will assume for this problem that the car is colliding with a wall that has no deformation. In this case the deformation is equal to 1 meter.
- Next, we need to determine the spring constant. The car is clearly not a traditional spring, but a front on collision can be studied very well to get an accurate representation of the spring constant of the car. For this example we will assume that the data collected by the car manufacturer shows a spring constant of 10,000 N/m.
- Finally, and the information into the formula above and we find F = 10,000 N/m * 1 m = 10,000 N.
- One last final step could be determine the resulting acceleration a human body feels during that time frame to determine the extent of injuries

## FAQ

**What is an impact force?**

Impact force is a term used in physics, specifically in mechanics, to describe a force of a short period of time when objects collide.

## Related Terms

impact force calculator |

impact force formula |

how to calculate impact force |

impact force |

impact force equation |

force of impact is the force |

impact force examples |

impact force calculator pounds |

how to calculate impact force of a falling object |

impact force of falling object |

impact force of falling object calculator |

how to calculate impact force of a projectile |

how to calculate g force on impact |

impact force physics |

the greater the of any vehicle the greater the force of impact |

force of falling object calculator |

average impact force |

g force calculator impact |

how to find force of impact |

car crash impact calculator |

drop test g force calculator |

measuring impact force |

impact force of a hammer |

peak impact force |

how to work out impact force |

free fall impact force calculator |

impact force calculator online |

how to calculate impact load |

car crash impact force |

water impact force |

define impact force |

how to calculate impact force of falling object |

how do you calculate impact force |

how to calculate force of impact of a falling object |

crash impact calculator |

impact force calculator lbs |

the force of impact |

calculate impact force collision |

how to determine force of impact |

free fall impact force |

force due to impact |

examples of impact force |

how to calculate the force of an impact |

landing gear impact force |

impact force of a person falling |

calculating force of a falling object |

car accident impact force |

how to calculate the impact force of a falling object |

impact force at 30 mph |

impact force meter |

how to determine impact force |

how to calculate impact force of a vehicle |

impact force from falling object calculator |

how to figure out force of impact |

how do you calculate force of impact |