What is the Physics involved in an airbag reducing injury?

Answer 1

An airbag supplies the necessary force to couteract our body. This in turn minimizes the force at which we are prepelled in the car. This is because the airbag spreads out the force over a wider area this reduces the injuries you are exposed to in the car.

Just to add a bit, The amount of damage done to a person depends on the change in momentum. Airbags reduce the amount of damage dealt to a person by extending the period of time they are subject to a force. Vents on the back of the airbags are what prevent you from hitting it just as hard as the dashboard and increase the stopping time as your weight pushes the nitrogen out of the bag...