Law of Inertia

Explanation:

This is a physics basic rule. A body in motion tends to stay in motion until something stops it. As a passenger in a vehicle you are traveling at the same speed and in the same direction as the vehicle itself, but are not a part of it. A force called “inertia” keeps the car, and you inside it, traveling forward until something stops it and you. The brakes stop the car by applying force against the direction of travel. You, not being an integral part of the car, have your own inertia, which tries to keep you moving at the same speed and direction you’ve been going. So, the brakes stop the car, but you keep going. Until, that is, the seat belt, firmly attached to the now stopped car, stops you. The reality is that you’re not thrown forward. Your inertia keeps you moving at the same speed, in the same direction, that you have been going, until something, in this case your seat belt, stops you. It’s important to realize that you and the car, while both traveling at the same speed and direction, have separate inertia. If you were belted in such a way that you couldn’t move separately from the car seat, which is firmly bolted to the car, you would share the car’s inertia and stop with it. But there is enough slack in a seat belt that as a physics problem, you and the car each have your own inertia, as you are two separate objects in this exercise. You will note that any loose objects in the car also have their own inertia, as they will fly forward when the brakes are applied. It’s basic physics.