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tapper of spines
03/07/2005, 01:14 PM
I haven't even finished reading your RK article yet. I'm sure I'll have questions when I do. I got stuck on the second paragraph, and felt compelled to start this thread.

This probably falls under the he-doesn't-have-enough-fibre-in-his-diet category, but as a physicist I find it rather irritating when people use the term "degrees Kelvin," an error that runs rampant throughout the aquarium hobby. No disrespect intended, but this is incorrect. It is "degrees Celsius" or "degrees Fahrenheit" but it is not "degrees Kelvin." It is pronounced "Kelvin." That's it. No extra "degrees" involved. "The surface of the sun has a temperature of fifty-six-hundred Kelvin." Ahhhh. Much better.

HTH
TOS

Skipper
03/07/2005, 01:25 PM
OK, TOS. I'm checking into this.

Thanks.

Skipper
03/07/2005, 03:12 PM
According to the CRC Handbook of Chemistry and Physics, it's listed as degrees Kelvin. If you have some other reference, I'd be glad to check it out.

Skipper
03/07/2005, 03:21 PM
Ok, I found another reference:

"In 1954, the definition of the Celsius scale itself was changed. Rather than using the freezing and boiling points of water at 1 atmosphere of pressure, the degree interval Celsius was set equal to the degree interval Kelvin, and 0 °C was set equal to 273.15 degree Kelvin. Thus, the Kelvin scale became the fundamental temperature scale. Its fundamental unit was the degree Kelvin, with the symbol °K. Unfortunately, here also the word degree introduced complications as temperature measurements became finer. For example, the metric system dictates that 0.01 meter is equal to 1 centimeter. However, is 0.01 degree Kelvin equal to 1 centidegree Kelvin, or 1 degree centiKelvin? In order to remove this ambiguity, scientists agreed in 1967 that degree Kelvin would no longer be used to describe the fundamental temperature interval. The fundamental temperature interval would be called simply kelvin (with a lowercase k), and the symbol would be K without any degree symbol (°). The temperature interval in the Celsius scale, however, would retain the word degree, the capitalized C in Celsius, and the symbol °C."

http://www.bartleby.com/64/C004/016.html

Skipper
03/07/2005, 03:23 PM
Hmmm....

tsquad
03/07/2005, 03:23 PM
We've always said "Degrees Kelvin" in science class, but for two reasons I trust you
1. I'm 15
2. Your occupation is "Magnetohydrodynamics" which just sounds incredibly intimidating.

tapper of spines
03/07/2005, 03:25 PM
My copy of the CRC, 66th edition, lists the unit of thermodynamic temperature as Kelvin (page F-247, "Units and Symbols for Units"). Of course, the 66th edition is rather old. Here are some other references:

http://physics.nist.gov/cuu/Units/units.html
http://www.chemie.fu-berlin.de/chemistry/general/si_en.html
http://www.ex.ac.uk/cimt/dictunit/dictunit.htm

But whatever. You can type "si units" into google and come up with the links as easily as I can.

TOS

tapper of spines
03/07/2005, 03:31 PM
Originally posted by tsquad
2. Your occupation is "Magnetohydrodynamics" which just sounds incredibly intimidating.

It's meant to be intimidating. :smokin: But I wouldn't get too worked up about it.

;)

TOS

Highlander
03/07/2005, 03:31 PM
The units are Kelvins.
I actually worked in the University department back in Scotland, where William Thompson, aka, Lord Kelvin, had developed and introduced the new temperature scale for absolute temperature:

http://understandingscience.ucc.ie/pages/sci_kelvin.htm

tapper of spines
03/07/2005, 03:36 PM
Thanks for the links guys. Very interesting.

Whatever your decision, Skipper, I've yet to meet a physicist or astronomer that calls it degrees Kelvin (and I've met a few physicists and astronomers ;) ). I've gotten the rant out of my system; if the biologists want to call it degrees Kelvin there is little more I can do about it.

TOS

Skipper
03/07/2005, 03:54 PM
Ok, thanks for the input everyone. I've made some changes to the article and included the link to the reference I found on the proper use of the term to help eliminate any possible confusion. The new version will be up shortly.