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From: bson@rice-chex.ai.mit.edu (Jan Brittenson)
Newsgroups: comp.sys.handhelds
Subject: Re: Units Problems...
Message-ID: <10994@life.ai.mit.edu>
Date: 25 Sep 90 17:03:36 GMT
References: <9682@ccncsu.ColoState.EDU>
Sender: news@ai.mit.edu
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In article <9682@ccncsu.ColoState.EDU>
   jn190068@longs.LANCE.ColoState.EDU (Jay Lewis Nestle) writes:

>	I was working on a simple heat transfer problem and was
>using my 48SX.  I was using C degrees, my answers seemed to be
>
>	enter 1 degree C twice then add them, the answer
>	is: 275.15 degrees C

If you do 1_K 1_C + you get 2_C. 
If you do 1_C 1_K + you get 275.15_K.
Same goes for F, but difference values.

   Assume we're adding 0C and 0C. What are we trying to accomplish?
Adding two freezing points? Doesn't make sense. You can add Kelvin and
Kelvin, and get Kelvin since it's an SI unit, but not C + C. It won't
make sense. You can add 1 to 1C and get 2C. What is the unit-less 1
then? Well, it's one C _scale unit_, i.e. 1K.

   Remember that 0C is 273.15K. If you add 0C to 0C, you'll have
2*273.15K.  To convert the answer back, subtract 273.15K, and you're
still left with 273.15C. So I'm afraid the 48 is doing the right thing
here. (Which presumably, is what you wanted like to hear, after all.
:-))