At 10:57 AM 6/30/02, "Erik Reuter" <[EMAIL PROTECTED]> wrote:
>On Sun, Jun 30, 2002 at 10:42:45AM -0500, Ronn Blankenship wrote:
> >
> > Only "close"?!
> >
> >
> > I'm offended!  ;-)
>
>Actually, yours are more accurate than mine :-) I tend to remember the
>heat produced by an average body as 100W



Well, if you figure 2,000 Calories/day instead of 2,500 (as you say, humans 
vary), that number would be pretty close.  And to be fair, in class I 
generally round it off to get 100W, so I can make the point that the amount 
of heat being generated by the average human body is about the same as that 
generated by a 100W light bulb (something with which most people are 
familiar), so the total amount of heat generated by the 30 or so bodies in 
the classroom is the same as if we put 30 100W bulbs in the room and turned 
them on, at which point the light usually goes on in a lot of eyes as they 
realize just why a room full of people gets so warm and stuffy so quickly.



>and the sunlight as 1kW/m^2, so
>I don't have to do the calculation or remember so many digits, I use the
>round numbers. Of course, humans and sunlight vary, so without specific
>details for each situation, the round numbers are fine.



I know.  But I figured I should give precise values for the number of 
Joules in a Calorie, the solar constant, etc, and having about half a 
dozen� scientific calculator programs available on this machine (not to 
mention the regular Windows calculator, MS Excel, and Mathematica), it 
wasn't too difficult to use those values to come up with an accurate answer.

At least I didn't go to the lengths of figuring the maximum (ca. 21 June of 
each year) and minimum (ca. 22 Dec) altitude of the Sun as seen in Texas 
(which specific location?) and multiply the 1.37 kW/m� (measured at normal 
incidence outside the atmosphere) by sin h, then try to estimate the energy 
loss due to atmospheric absorption and scattering . . .

_____
�Each one has features that the others don't.  Which is why I still have my 
HP-16C, also.  As well as an old Sharp or Casio financial calculator which 
prints out its results on a little tiny roll of paper.


-- Ronn! :)

Ronn Blankenship
Instructor of Astronomy/Planetary Science
University of Montevallo
Montevallo, AL

Disclaimer:  Unless specifically stated otherwise, any opinions contained 
herein are the personal opinions of the author and do not represent the 
official position of the University of Montevallo.

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