re: Audi A5?!?!

["Smith, Kirby A" <kirby.a.smith@lmco.com>]

"Greg Johnson" <gregsj@iea.com> wrote, in part:
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Observations: the "A5" is 400 lbs lighter than the A6 and about the
same as the A4.  The "A5" is a lot wider than both of the Audis yet its drag
coef is less than the A6's.  Go figure.
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Drag coeficient is not drag force.  You have to multiply by the reference
area that was used (probably the frontal section for cars, but not
airplanes) air density, and by the velocity squared (times one-half, I
think).  It is unlikely the reference area is the same on the two cars, and
the coeficient itself is going to be related not only to shape , but also
length.

                .... Kirby   (Kirby A. Smith)
                              2 x 1988 90q
                          New Hampshire USA