Science magazine (AAAS) is one of the best American magazines now available
now for reading articles that use only SI units. They even normally write
"micrometer" instead of "micron", unless the author of a research article has
used that antiquated name. Occaisionally, they will provide ifp equivalents
parenthetically and will use them in primary position only if the context or
a quote demands it ("footlong hot dogs" instead of "30-cm-long hot dogs").
Only rarely anymore do they really screw things up. Just as I was about to
turn in my hunting license, I came across this rare quarry.
Jim
---------- Forwarded Message ----------
Dear editor,
Someone snuck a mangled unit of measurement past you onto the printed page
and it muddled the measurement beyond comprehension.
In the Random Samples article, "Boa's Hold Measured", on 2002 April 19 it is
reported, "A 5.5-meter python, for example, can create a force of about 1
kilogram per square centimeter....". The units used are appropriate for areal
mass density, not for force. The preceding sentence describes a plot of
pressure exerted on the sensor, so perhaps the writer was really aiming at
pressure, not force -- hence the "per square centimeter". If pressure were
meant, I would expect to see "newtons per square meter" or "pascals". If
force were meant, I would expect to see "newtons".
I'm still in the dark about these snakes. Can you tell me how hard a typical
python's can squeeze its prey? I would suppose that since the applied force
is distributed over the area of contact, pressure would be most appropriate
quantity to report this in.
regards,
Jim Frysinger
--
James R. Frysinger University/College of Charleston
10 Captiva Row Dept. of Physics and Astronomy
Charleston, SC 29407 66 George Street
843.225.0805 Charleston, SC 29424
http://www.cofc.edu/~frysingj [EMAIL PROTECTED]
Cert. Adv. Metrication Specialist 843.953.7644
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