Klarinet Archive - Posting 000076.txt from 2008/09

From: "Keith" <bowenk@-----.com>
Subj: RE: [kl] Re: Warm Air / Cold Air
Date: Tue, 23 Sep 2008 04:29:16 -0400


Keith wrote:
>> I am prepared to be argued out of this view but the arguments has =
better be good :). I loathe bad science.

>Basic simple and dumb experiment -- blow on your hand, hard and with a
narrow lip opening, or slow and with a wider opening -- it _feels_
colder and warmer, respectively. But that would be wind chill rather
than a really significant temperature difference, I suspect. :-)

Yes, as an experiment it is dumb! As you suspect, this is not measuring =
the temperature of the air, only of the skin, and as you say (and as I =
said too), wind chill is likely to be a much bigger effect. At the very =
least, you have not distinguished the effects, so it is a bad experiment =
for measuring air temperature.

You have a big thermal reservoir in your chest and mouth, and very good =
contact between this and the air (obviously, for this is how oxygen gets =
in the blood). To talk accurately about blowing with warm or cold air, =
you have to explain how this temperature is altered. Merely expelling it =
slowly or rapidly will have negligible effect.

>I suppose that blowing-on-the-hand exercise might be useful to give a
student a sense of what different kinds of breath they can use.
Alternatively it might be a good way of getting the head out of the way
of what's physically happening...

Maybe so, but isn't it simpler, as well as more accurate, to say blow =
harder or softer?

Keith

------------------------------------------------------------------

__________ Information from ESET Smart Security, version of virus =
signature database 3462 (20080923) __________

The message was checked by ESET Smart Security.

http://www.eset.com

=20

__________ Information from ESET Smart Security, version of virus =
signature database 3462 (20080923) __________

The message was checked by ESET Smart Security.

http://www.eset.com
=20

------------------------------------------------------------------