Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Car Crash Loads

[Subject Prev][Subject Next][Thread Prev][Thread Next]
According to Newton's Law,
Impressed Force=rate of change of momentum.
mass=weight/g=3500/32.2=109 (approx.)
velocity before impact=60 mph=88 ft/sec.
If velocity after impact is assumed as -15 mph (=22 ft/sec), and the change
happens in 1 sec., then
change of momentum=109*88-109*(-22)=11990 ft.lbs
Velocity after impact is negative because the vehicle will travel in opposite
direction after impact.

Well, that gives some method of calculating impact force.


Parkerres(--nospam--at) wrote:

> To all:
> A client asked me today to give him a "simple" formula to translate a speeding
> car into an impact load.  For example, if a 3500 pound car is traveling at 60
> mph and hits a wall, what is the impact force?  Of course, my brain is so
> clogged with Code regulations, I only have vague recolations of the physics
> involved with solving this problem.
> Any input would be appreciated.
> Thanks,
> Bruce Resnick, SE
> Parker Resnick Str. Eng.