Settting up force problem with only mass and velocity provided

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
1 reply · 1K views
Zontar
Messages
3
Reaction score
0

Homework Statement



A 60kg person is in a head-on collision. The car's speed at impact is 15 m/s. Estimate the net force on the person if they are wearing their seat belt and the air bags deploy. When these two events occur, the passenger decelerates over a distance of 1 m.

Homework Equations



This is a force problem so I reasoned I would need to use F=ma. Below explains other equations I try.

The Attempt at a Solution



This is the way I saw it. I need "F" and I have "m", but they gave me a velocity instead of an acceleration. Although I need an acceleration, I don't know how to set up the kinematics problem (I greatly struggle with this part of each problem) and I try all different things that don't make sense. So I have V_f = 0 m/s while V_i = 15 m/s but all the equations I tried still have an unknown "time" or "distance", which I don't understand how to extrapolate out of the problem. Would I use D_i as 1 m and D_f as 0 m since it decelerates over a distance of 1 m?
 
Physics news on Phys.org