Force & Motion Homework: How to Calculate Force from Restricted Motion

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To calculate the force acting on a passenger during a car crash, one must consider the kinetic energy of the car and the work done as the passenger moves into the airbag. The car's initial speed of 48 km/h translates to a certain kinetic energy, which is dissipated as the passenger comes to rest over a distance of 53 cm. Although the concept of kinetic energy hasn't been covered in class yet, it is essential for solving this problem. The mass of the passenger is given as 40 kg, which will be needed to calculate the force. Understanding these principles will guide the correct approach to finding the force exerted on the passenger's torso.
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Homework Statement


A car traveling at 48 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 53 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant) acts on the passenger's upper torso, which has a mass of 40 kg?


Homework Equations





The Attempt at a Solution


Can somebody please help me with an approach to this type of problem.
 
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Try using conservation of energy. The car has kinetic energy and when it hits, work is done in moving the passenger 53cm into the air-bag.
 
Hmm, we have not gone over kinetic energy in class yet. I'll read up on it, and post an approach and see if it's right.
 

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