Re: Our 'humiliating' mistakes.

["Rick Tarara" <rbtarara@sprynet.com>]

Here in the U.S. the Calorie is used in place of the 'better' kilocalorie
when reporting caloric content of foods.  The calorie (4.178 Joules)
conforms to standard definitions--the amount of (heat/work/thermal
energy???) necessary to raise the temperature of gram of water by one
degree Celsius (at standard atmospheric pressure).  It IS a major source of
confusion for students who are familiar with 3000 Calorie diets, 300
Calorie candy bars, and the like.   The distinction exists because of the
usage outside the scientific community which is not likely to go away. 
Therefore we (the physics instructors) must deal with it when dealing with
calorimetry (unless one can find a book and data tables that avoid the use
of calories as a unit altogether.)

What's the convention up there in Canada, Leigh?

Rick
----------
> From: msantos@etse.urv.es
> To: phys-l@atlantis.cc.uwf.edu
> Subject: Re: Our 'humiliating' mistakes.
> Date: Saturday, September 13, 1997 3:16 PM
>
> > An error of the same sort as mine was made once by Farrington Daniels,
> > a Chemistry Professor at the University of Wisconsin. Just before a
> > freshman lecture Daniels did a calculation which indicated to him that
> > the metabolic heat required to melt thirty grams of ice would offset
> > 3000 Calories of dietary intake. He made the mistake of blurting out
> > his discovery to the class, at which point a student respectfully
> > inquired about the possibility that Daniels had confused calories and
> > Calories. Of course he had; the requirement was to eat thirty
> > ... 
> > Leigh
> Hi all,
>  I remember once the list advertised me ther was a difference
> between 'calories' and 'Calories'...
> Is this really a standard? In the I.S. of units, we are told
> to use :
> 	kC, MC, mC, muC, pC,...
>
> I guess it is only a U.S. distinction, I've never before seen it.
>
> Indeed, is it really usefui? convenient? 
> I can hardly accept that such tiny differences can be given
> any meaning without introducing a source of ambiguity, 
> misunderstandings. 
>
> Physics tries to provide a language fre from ambiguities, isn't
> that tiny distinction between 'c' an 'C' put too far?
>
> What sense does it has to discuss if 's' is more
> adequate than 'seg' or not if one accepts such former
> distinction?
>
> I hope that nice atmosphere againts mistakes,errors and
> silly questions is still alive...
>
> Regards,
> M.A.Santos
> msantos@etse.urv.es