Forces applied to occupants in car crash (important for assignment )

AI Thread Summary
For a physics assignment comparing forces in car crashes, the discussion focuses on two vehicles traveling at 60 km/h, one with a crumple zone and one without. The key point is that the car stopping in 0.04 seconds experiences greater force than the one stopping in 0.1 seconds, illustrating the safety benefits of crumple zones. Participants suggest using impulse and momentum concepts, along with equations of motion, to calculate the forces involved. The formula F=ma can be applied once acceleration is determined from the stopping time. Understanding these principles is crucial for demonstrating the differences in occupant safety during collisions.
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Forces applied to occupants in car crash (important for assignment!)

Ok so I'm in grade 10 at school and for my physics assignment I'm comparing the forces applied on the vehicle (or occupants) in a collision, where one car has a crumple zone and the other one doesn't. If they were both traveling at 60km/h and ran into a wall, and one stopped in 0.1 seconds and the other stopped in 0.04 seconds, what are the forces in each crash? I tried using formula like F=gm and stuff but it doesn't seem to suit my equation, as I'm expecting there to be more force applied on the vehicle with a stopping distance of 0.04 seconds, because I'm giving a real life example of how crumple zones are safer than a car with no crumple zone. Sorry if this was hard to understand because it was badly worded but I've been working on this assignment for hours and I'm tired. The assignment is due in 3 days so quick replies will be much appreciated. Thank you to anyone who can help!
 
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187 god said:
Ok so I'm in grade 10 at school and for my physics assignment I'm comparing the forces applied on the vehicle (or occupants) in a collision, where one car has a crumple zone and the other one doesn't. If they were both traveling at 60km/h and ran into a wall, and one stopped in 0.1 seconds and the other stopped in 0.04 seconds, what are the forces in each crash? I tried using formula like F=gm and stuff but it doesn't seem to suit my equation, as I'm expecting there to be more force applied on the vehicle with a stopping distance of 0.04 seconds, because I'm giving a real life example of how crumple zones are safer than a car with no crumple zone. Sorry if this was hard to understand because it was badly worded but I've been working on this assignment for hours and I'm tired. The assignment is due in 3 days so quick replies will be much appreciated. Thank you to anyone who can help!
Have you come across the concept of impulse and momentum?
 


You could assume uniform deceleration and apply the equation of motion..

http://en.wikipedia.org/wiki/Equations_of_motion

V= at +u

Rearrange to give an equation for "a".

Convert to F if you know the mass.
 
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