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Re: A High kcal Question



At 20:19 11/3/99 -0600, you wrote:
For some, fall brings about thoughts of pumpkin pie topped with whipped
cream. Our department secretary asked me how heavy cream, when whipped,
becomes stiff. Any ideas?

David Marx
Southern Illinois University

Neglecting any polymeric features, this question is an interesting
illustration of the virtues of occupying space for a load bearing
structure.
You are aware of the great importance of disposing structural mass
far from the center in a bridge beam - you recall the economy of timber
that was achieved in converting heavy roof rafters to trusses.

NASA was shouting the virtues of a novel silica aerogel this
- perhaps a little too loudly. The PR department was pointing to
aerogels "weighing less than air" which was not quite true.

Apparently a structural gel of this kind in vacuum can weigh less
than the same volume of air - not quite the same concept as a
"solid, buoyant in air" though.

Airplanes have been demonstrated, whose wings are inflated, and
fuel tanks with flexible skins have been towed at sea.

So trapping air in a liquid has an opportunity to enhance its
structural integrity, on general principles.

brian whatcott <inet@intellisys.net>
Altus OK