I think that's where surface tension figures into it. Nature will try to take
the falling sphere and elongate it into a better aerodynamic shape, but it is
always a compromise because the medium wants to stay in a sphere. Lead has
much higher surface tension than water, so it stays nearly shperical. Water
stretches out a little into the common "tear drop" shape. A lighter liquid,
such as alcohol, would stretch out even longer. The wind resistance vs the
surface tension would sort of determine the amount of stretch. Now that's a
realy layman's opinion, since I am in no way a hydraulic or aeronautical
engineer.
Dick J
Michael Siewert <mdsiewer@ucalgary.ca> wrote:
I keep seeing the tear-drop referrenced as a natural aerodymamic
shape. It bugs me. 'cause raindrops are pretty much spherical.
Liquids take on a spherical shape when falling through air, that's how
lead shot is made.
http://www.eng.vt.edu/fluids/msc/my_pages/raindrops/raindrop.htm
--
--
Michael D. Siewert
Department of Chemistry, University of Calgary
Calgary, Alberta, Canada
tel. 403 220 7228
fax. 403 289 9488
http://www.ucalgary.ca/~mdsiewer
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