Which three factors determine the force of impact in a collision?

Which three factors determine the force of impact in a collision?

• A. Speed, Weight, Distance of impact
• B. Speed, Weight
• C. Weight, Distance
• D. Speed, Distance

Answer: (A)

When a crash happens, the car must dissipate its kinetic energy, and that energy depends on how heavy the car is and how fast it’s going. The more mass (weight) the car has, the more energy must be removed. The faster you’re traveling, the more energy there is to dissipate (since kinetic energy grows with the square of speed). How quickly that energy is removed matters too: if the stopping distance during the crash is longer, the same energy can be spread over a longer time and distance, reducing the peak force experienced at any moment. A handy way to think about it is F ≈ (1/2 m v^2) / d, where m is mass, v is speed, and d is the distance over which you stop. This shows why speed, weight, and the distance of impact all matter together. The faster you’re going and the heavier the vehicle, the more energy must be absorbed; increasing the stopping distance (crumple zone, safety features) lowers the force on you inside the vehicle. That’s why the three factors—speed, weight, and distance of impact—are all essential to determine the force of impact.

When a crash happens, the car must dissipate its kinetic energy, and that energy depends on how heavy the car is and how fast it’s going. The more mass (weight) the car has, the more energy must be removed. The faster you’re traveling, the more energy there is to dissipate (since kinetic energy grows with the square of speed). How quickly that energy is removed matters too: if the stopping distance during the crash is longer, the same energy can be spread over a longer time and distance, reducing the peak force experienced at any moment.

A handy way to think about it is F ≈ (1/2 m v^2) / d, where m is mass, v is speed, and d is the distance over which you stop. This shows why speed, weight, and the distance of impact all matter together. The faster you’re going and the heavier the vehicle, the more energy must be absorbed; increasing the stopping distance (crumple zone, safety features) lowers the force on you inside the vehicle.

That’s why the three factors—speed, weight, and distance of impact—are all essential to determine the force of impact.