RE: Fwd: Audi A8 Achieves Highest Possible Safety Test Rating

["Rob Winchell" <rbw@avs.com>]

Doesn't that assume the cars are identical? What if one car is 2000 pounds
and one is 5000 pounds?



> -----Original Message-----
> From: owner-quattro@coimbra.ans.net
> [mailto:owner-quattro@coimbra.ans.net]On Behalf Of Orin Eman
> Sent: Wednesday, September 16, 1998 1:19 PM
> To: four.rings@mcione.com
> Cc: quattro@coimbra.ans.net
> Subject: Re: Fwd: Audi A8 Achieves Highest Possible Safety Test Rating
>
>
>
> > An excerpt from the newswire post:
>
> > > To collect this data, vehicles are crashed into a fixed
> barrier at 35 miles
> > > per hour with instrumented dummies registering impact forces
> during the crash.
> > > The force is equivalent to a head-on collision between two
> identical vehicles,
> > > each moving at 35 mph.
>
> > No, it will be equivalent to a head-on collision between two
> identical vehicles,
> > each moving at 17.5 mph.
>
> In terms of kinetic energy that has to be dissipated, the 35 mph figure
> is correct...  A car travelling at 35mph, ending up at rest must
> dissipate the same amount of energy regardless of what it crashes into.
>
> Looking at forces, the concrete barrier provides whatever force
> is required
> to decelerate the car.  In the case of the head on crash, the
> same force is
> required... by each car.  If you then look at Newton's laws - equal and
> opposite reaction.  Each car supplies the reaction required by the other!
>
> Orin.
>