Re: COLLISION 2

[Jim Green <JMGreen@SISNA.COM>]

> I have tried thinking of the deformation as a giant spring between the
> two cars. In the elastic case the energy stored in the spring is
> recovered as kinetic energy. In the case of the inelastic collision, the
> spring finds itself permanently caught in a compressed condition as they
> couple and cannot come apart. Is this a reasonable model to present to
> beginning students?

David, this seems OK -- but I would add that the spring would be very hot
and that the original experiment is not all that real -- ie real railroad
cars don't bounce elastically -- that is one reason they make all that
noise even if they don't couple. (:-)

Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen