From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
Newsgroups: sci.skeptic
Subject: Re: Well known scientific facts
Date: 29 Sep 1992 17:34:59 GMT
Organization: HST Wide Field/Planetary Camera
Reply-To: carl@SOL1.GPS.CALTECH.EDU
NNTP-Posting-Host: sol1.gps.caltech.edu

In article <1992Sep29.150200.31779@mp.cs.niu.edu>, you write:
=>>I'll give you my informal and unofficial definition of fever.  (No, I do
=>>not have any medical qualifications).
=>
=>Nor, apparently, any background in physics.
=
=Thanks for the insult.

No insult intended.  Just an observation.

What background (if any) do you have in physics?

Just the standard two years required of Caltech undergrads:  Classical
mechanics, special relativity, a bit of general relativity, E&M, and some QM.
And the mathematics to go with it, including dealing with multivariable
non-linear second-order differential equations.

=Would you care to post your wonderful theories about physics for all to
=see, so that you too can be publically ridiculed?

No need to post the heat equation, you'll find it in any decent college physics
text.  Besides, ASCII doesn't have the proper symbol set.

=The fact is, when the thermometer is inserted in the mouth, the temperature
=of the oral cavity is likely to be below body temperature (except on
=very hot days) because the mouth is open and cooled by the ambient air
=and by evaporation.  The rapidity with which the thermometer reaches an
=equilibrium temperature is a good measure of the rapidity with which
=the oral cavity reaches body temperature.  I am assuming the thermometer
=is in contact with some surface, usually the tongue.  For someone with
=a fever, this rise in temperature is typically quite rapid, for the
=blood vessels are dilated.  When there is no fever the blood vessels to
=the mouth and tongue are not dilated so do not carry nearly as much warm
=blood to the area.  For exactly the same reason, many parents can
=recognize a child's fever by just feeling the forehead.
=
=Now please expound on your wonderful theories of physics and the heat
=equation, and their relation to this.

Certainly:  The rate at which heat is conducted between a source and a sink
is proportional to the difference in temperatures of the source and the sink.
If the temperature of the mercury starts rising quickly, it means either:
	1)  The thermometer was cold
	2)  The thing being measured is hot.
Whichever the cause for the initial rapid rise, the thermometer eventually ends
up at the temperature of the thing whose temperature is being measured.  So
watching the rate of initial rise in temperature is less reliable than checking
the final temperature.  I guess maybe the people who've been making
thermometers (not just fever thermometers, but those that are used in labs, and
so forth) have actually had some idea of what they were doing for the past
hundred years or more, eh?
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL

Disclaimer:  Hey, I understand VAXen and VMS.  That's what I get paid for.  My
understanding of astronomy is purely at the amateur level (or below).  So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it.  If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
Newsgroups: sci.skeptic