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Dumb car crash question. I think this is a conservation of momentum problem.
In one scenario, two 4000 lb cars (car A and car B) each traveling at exactly 35 MPH in opposite directions have a perfect head on collision with each other.
In the other scenario, one 4000 lb car (Car A) traveling at 35 MPH hits a steel reinforced concrete bridge abutment (i.e. a huge mass with zero speed.)
Which Car A sustains more 'damage'?
My gut feel is that both experience exactly the same crash damage, but I'm at a loss to describe why.
(Question inspired by a temporary stretch of freeway near my home, with just a painted double line between opposing directions of traffic.. It's quite scary...)