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Archive 1 | Archive 2 |
Isnt water meant to infer H2o is in a liquid form? Isnt steam meant to infer H2o being near a gasious form? isnt Ice meant to infer H2o being in state with near zero excitation to it? me thinks water should be replaced with H2o
Is the Kelvin temperature scale actually supposed to be written as a lower-case k? I thought k stood for kilo- and K stood for Kelvins. -- 24.72.34.179 22:44, 14 Jun 2004 (UTC)
I think they meant that:
200 K = 200 kelvins
200 A = 200 amperes
Perhaps the wording needs some clarification, or perhaps it's unnecessary. -- Curps 23:46, 14 Jun 2004 (UTC)
Page 31 of the United States National Institue of Standards and Technology (NIST) Special Puplication 811 (Guide for the Use of the International System of Units (SI)) states that unit names should be spelled out in full like any other English noun, with lower-case letters, except at the start of a sentence or in a title. However, if you write "degree Kelvin", Kelvin should be capitalized (since it's a type of degree, same way you'd write "Kennedy High School" and "high school") The publication actually uses celsius for the example but it's the same principle. A capital K should be used when abbreviating, since the unit is named after a person. -- Uberdog 02:14, 30 Jun 2004 (UTC)
In case anyone's interested, here's a NASA styleguide, which is where I confirmed my suspicion that a space belongs between the number and the symbol for Kelvins, unlike in many places in Wikipedia. NASA occasionally has trouble with units, but hopefully they can spell them right. -- Tantalate 01:47, 4 Aug 2004 (UTC)
Any reason why both 273.16 ("...one kelvin is the fraction 1/273.16 of...") and 273.15 ("°C = K − 273.15") is used? which is the right one?
What about the title of the article? Does it come under starting a sentence (therefore a capital) or should it start in lowercase to show that it is not capitalised at the middle of sentenses? I thought it should be lowercase, but that was removed and aparently this has been discussed before. Daniel 23:43, 29 January 2006 (UTC)
I just had an edit of mine reverted and I'd like to explain myself. The BIPM brochure on kelvin, which link I added to the article, states the following (emphasis is in the original):
I re-stated and summarized this as follows:
I think this is a fairly faithful rendering of the BIPM's description, but I'm open to discussion on the point. Our prior (and, after the revert, our current) definition reads as follows:
The problem with this description is that it does not make any distinction between the kelvin unit of temperature versus the Kelvin thermodynamic temperature scale, which measures temperature relative to absolute zero. For example, take the statement that "zero kelvins is absolute zero". Consider the question: what temperature change is necessary in water at standard temperature and pressure in order to liquefy it? The answer is "zero kelvins", but this most certainly does not indicate that the liquefied water would be at absolute zero.
My version of the definition used terms and phrases introduced by the BIPM brochure:
It also includes some embellishments I thought were fairly benign (and were pre-existing):
All in all, I think this is a fairly uncontrovercial definition of the kelvin, and I'd like to reinstate it, or something like it. -- Doradus 03:30, Dec 30, 2004 (UTC)
The factual accuracy of part of this article is
disputed. The dispute is about Definition of Kelvin. (March 2008) |
When I look this up, there seems to be a descrepency between the definition of absolute zero with Zero Kelvin and what is provided by my Physics professor and my physics textbook. Here, it says ..."is measured with respect to absolute zero, where molecular motion stops (except for the residual quantum mechanical zero-point energy)." However, my physics professor and my textbook explicitly disagrees with that exact definition and the textbook says (emphasis mine): "Absolute zero is not the temperature at which all molecular motion ceases."
As such, the book continues to describe it as: "One way to determine absolute zero is to graph the pressure of a fixed volume of gas as a function of temperature." So the book graphs the temperature of several gases' pressure as temperature drops, and they after many readings, you can then continue to "extrapolate the linear relationship, as described by the Ideal Gas Law." This results in a point in which this converges to a point called absolute zero. My textbook describes it as: "The absolute zero of temperature can also be described as that temperature at which all of the energy that can be removed from the object has been removed."
The textbook I used is: "The World of Physics: Mysteries Magic & Myth" by Dr. John W. Jewett, Jr., Published by: Harcourt College Publishters. ISBN 0-03-031944-7. If someone can verify/support this (or disprove it) with other sources, it would be appreciated. -- Akosygin 22:43, 23 January 2006 (UTC)
Is the "technical limitations" note necessary? "Kelvin" is capitalized at the start of a sentence or in a title, just like cat, washing machine, or any other common noun. The page follows Wikipedia's capitalization convention; what's wrong with that? -- tilde 00:21, September 7, 2005 (UTC)
Which is it? I thought this unit was always said in the singular. That is, "0 kelvin", "10 kelvin", "a difference of 42 kelvin", "measured in kelvin", and never "kelvins". Is that right? — BenFrantzDale 22:32, 9 October 2005 (UTC)
How can Kelvin be converted into electron volt, let alone with a dimensionless conversion factor as in this article? Temperature and energy are different physical properties. Kelvin is a base unit and . -- Hardy 21:46, 16 October 2005 (UTC)
So do you guys have the rigth formula? Looks kinda silly, a disputed tag on a formula... -- The Minister of War 17:01, 24 November 2005 (UTC)
"Why the overline?"
I arrived at this talk page ready to complain that the "Temperature and energy" section (version as of now) is irrelevant and should be removed. Seeing that Hardy already made this complaint months ago, I'm removing it. Melchoir 11:32, 25 February 2006 (UTC)
The "conversion" between kelvin and electronvolts still does not make sense because these are differenz units as stated above (). An IP user wrote months ago "they are not compatible". Otherwise we could further convert eV into grams using the equation E=m*c². It may be true that eV is used as equivalent for K in certain contexts but that is no conversion as from °C to K etc. "1 eV is equivalent to a temperature of 11,604 kelvin" is not the same as "1 eV = 11,604 kelvin". -- Hardy 19:24, 16 August 2006 (UTC)
The symbol '°' is used when refering to a specific temperature (except for the absolute scale when the unit is used directly without any further symbol). However when refering to the temperature interval, the term 'deg' is used to avoid confusion.
Thus 1 deg Celcius = 1 deg Kelvin. But 1 °Celcius <> 1 Kelvin.
I made some changes in the convoluted explanations which included "Notwithstanding the naming convention historically used for the other temperature scales, SI unit names are never capitalized."
One of the biggest problems, of course, with this explanation is that the "degree Celsius" is an SI unit, a "derived unit with a special name", listed in "Table 3 SI derived units with special names and symbols" in the BIPM's SI brochure, for example.
The change isn't due to some inherent difference between kelvins and various other kinds of degrees. It remains "degrees Celsius". Furthermore, though the CGPM doesn't concern itself with the non-metric units, it also remains not only "degrees Fahrenheit" but also "degrees Rankine" in the other absolute temperature scale. Gene Nygaard 12:42, 14 June 2006 (UTC)
Citations are not required for obvious observations. Just look at scientific papers or technical articles on precision temperature measurement instrumentation. Check out the first paragraph of this article on SPRDTs 304 KB PDF. The scientific world abounds with this mixed use. It's hard to find a rational explanation for why this practice exists and a Wikipedia article on the kelvin is the perfect location for it. An article in Wikipedia can give the explanation that the BIPM's rule officially allowing the °C to be used to express an increment should have settled the issue and the scientific world is retarded (but I doubt that is a very satisfactory way of addressing the issue). Greg L 19:33, 14 June 2006 (UTC)
The imporant issue in science papers is the unambiguous communication of temperature values and uncertainties. See this NASA link which referrs to "An average liner metal temperature of 915 K, 355 kelvins greater than…" This is common practice in real-world science that is observed for a very good reason: it avoids confusion. The reasons underlying this practice should be explained even if it isn't sanctified by an international body. The very heading of this section ("Why technical articles use a mix of kelvin and Celsius scales") betrays its reason for existence: to simply explain why it is done this way. This is a community resource and you are free to contribute to this article. I hope you can make this section interesting, truthfull, and informative. If you think the whole section should be deleted, I can't stop you and don't have time to play "musical reverts" Greg L 22:53, 14 June 2006 (UTC)
Have you considered asking a Ph.D. chemist about the mixed use of °C and kelvins in scientific papers? Greg L 03:54, 15 June 2006 (UTC)
Please don't remove multiples, for consistency they are in all seven base SI units.
PLEASE GIVE THE HIGH VOLTAGE BETWEEN LOW VOLTAGE
I think this unit being named after Baron Kelvin should be mentioned earlier than it is now, perhaps even in the first sentence as it is with Celsius. I think finding out who a unit is named after is often important to readers. What do others think? -- Allen 06:19, 12 September 2006 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | Archive 2 |
Isnt water meant to infer H2o is in a liquid form? Isnt steam meant to infer H2o being near a gasious form? isnt Ice meant to infer H2o being in state with near zero excitation to it? me thinks water should be replaced with H2o
Is the Kelvin temperature scale actually supposed to be written as a lower-case k? I thought k stood for kilo- and K stood for Kelvins. -- 24.72.34.179 22:44, 14 Jun 2004 (UTC)
I think they meant that:
200 K = 200 kelvins
200 A = 200 amperes
Perhaps the wording needs some clarification, or perhaps it's unnecessary. -- Curps 23:46, 14 Jun 2004 (UTC)
Page 31 of the United States National Institue of Standards and Technology (NIST) Special Puplication 811 (Guide for the Use of the International System of Units (SI)) states that unit names should be spelled out in full like any other English noun, with lower-case letters, except at the start of a sentence or in a title. However, if you write "degree Kelvin", Kelvin should be capitalized (since it's a type of degree, same way you'd write "Kennedy High School" and "high school") The publication actually uses celsius for the example but it's the same principle. A capital K should be used when abbreviating, since the unit is named after a person. -- Uberdog 02:14, 30 Jun 2004 (UTC)
In case anyone's interested, here's a NASA styleguide, which is where I confirmed my suspicion that a space belongs between the number and the symbol for Kelvins, unlike in many places in Wikipedia. NASA occasionally has trouble with units, but hopefully they can spell them right. -- Tantalate 01:47, 4 Aug 2004 (UTC)
Any reason why both 273.16 ("...one kelvin is the fraction 1/273.16 of...") and 273.15 ("°C = K − 273.15") is used? which is the right one?
What about the title of the article? Does it come under starting a sentence (therefore a capital) or should it start in lowercase to show that it is not capitalised at the middle of sentenses? I thought it should be lowercase, but that was removed and aparently this has been discussed before. Daniel 23:43, 29 January 2006 (UTC)
I just had an edit of mine reverted and I'd like to explain myself. The BIPM brochure on kelvin, which link I added to the article, states the following (emphasis is in the original):
I re-stated and summarized this as follows:
I think this is a fairly faithful rendering of the BIPM's description, but I'm open to discussion on the point. Our prior (and, after the revert, our current) definition reads as follows:
The problem with this description is that it does not make any distinction between the kelvin unit of temperature versus the Kelvin thermodynamic temperature scale, which measures temperature relative to absolute zero. For example, take the statement that "zero kelvins is absolute zero". Consider the question: what temperature change is necessary in water at standard temperature and pressure in order to liquefy it? The answer is "zero kelvins", but this most certainly does not indicate that the liquefied water would be at absolute zero.
My version of the definition used terms and phrases introduced by the BIPM brochure:
It also includes some embellishments I thought were fairly benign (and were pre-existing):
All in all, I think this is a fairly uncontrovercial definition of the kelvin, and I'd like to reinstate it, or something like it. -- Doradus 03:30, Dec 30, 2004 (UTC)
The factual accuracy of part of this article is
disputed. The dispute is about Definition of Kelvin. (March 2008) |
When I look this up, there seems to be a descrepency between the definition of absolute zero with Zero Kelvin and what is provided by my Physics professor and my physics textbook. Here, it says ..."is measured with respect to absolute zero, where molecular motion stops (except for the residual quantum mechanical zero-point energy)." However, my physics professor and my textbook explicitly disagrees with that exact definition and the textbook says (emphasis mine): "Absolute zero is not the temperature at which all molecular motion ceases."
As such, the book continues to describe it as: "One way to determine absolute zero is to graph the pressure of a fixed volume of gas as a function of temperature." So the book graphs the temperature of several gases' pressure as temperature drops, and they after many readings, you can then continue to "extrapolate the linear relationship, as described by the Ideal Gas Law." This results in a point in which this converges to a point called absolute zero. My textbook describes it as: "The absolute zero of temperature can also be described as that temperature at which all of the energy that can be removed from the object has been removed."
The textbook I used is: "The World of Physics: Mysteries Magic & Myth" by Dr. John W. Jewett, Jr., Published by: Harcourt College Publishters. ISBN 0-03-031944-7. If someone can verify/support this (or disprove it) with other sources, it would be appreciated. -- Akosygin 22:43, 23 January 2006 (UTC)
Is the "technical limitations" note necessary? "Kelvin" is capitalized at the start of a sentence or in a title, just like cat, washing machine, or any other common noun. The page follows Wikipedia's capitalization convention; what's wrong with that? -- tilde 00:21, September 7, 2005 (UTC)
Which is it? I thought this unit was always said in the singular. That is, "0 kelvin", "10 kelvin", "a difference of 42 kelvin", "measured in kelvin", and never "kelvins". Is that right? — BenFrantzDale 22:32, 9 October 2005 (UTC)
How can Kelvin be converted into electron volt, let alone with a dimensionless conversion factor as in this article? Temperature and energy are different physical properties. Kelvin is a base unit and . -- Hardy 21:46, 16 October 2005 (UTC)
So do you guys have the rigth formula? Looks kinda silly, a disputed tag on a formula... -- The Minister of War 17:01, 24 November 2005 (UTC)
"Why the overline?"
I arrived at this talk page ready to complain that the "Temperature and energy" section (version as of now) is irrelevant and should be removed. Seeing that Hardy already made this complaint months ago, I'm removing it. Melchoir 11:32, 25 February 2006 (UTC)
The "conversion" between kelvin and electronvolts still does not make sense because these are differenz units as stated above (). An IP user wrote months ago "they are not compatible". Otherwise we could further convert eV into grams using the equation E=m*c². It may be true that eV is used as equivalent for K in certain contexts but that is no conversion as from °C to K etc. "1 eV is equivalent to a temperature of 11,604 kelvin" is not the same as "1 eV = 11,604 kelvin". -- Hardy 19:24, 16 August 2006 (UTC)
The symbol '°' is used when refering to a specific temperature (except for the absolute scale when the unit is used directly without any further symbol). However when refering to the temperature interval, the term 'deg' is used to avoid confusion.
Thus 1 deg Celcius = 1 deg Kelvin. But 1 °Celcius <> 1 Kelvin.
I made some changes in the convoluted explanations which included "Notwithstanding the naming convention historically used for the other temperature scales, SI unit names are never capitalized."
One of the biggest problems, of course, with this explanation is that the "degree Celsius" is an SI unit, a "derived unit with a special name", listed in "Table 3 SI derived units with special names and symbols" in the BIPM's SI brochure, for example.
The change isn't due to some inherent difference between kelvins and various other kinds of degrees. It remains "degrees Celsius". Furthermore, though the CGPM doesn't concern itself with the non-metric units, it also remains not only "degrees Fahrenheit" but also "degrees Rankine" in the other absolute temperature scale. Gene Nygaard 12:42, 14 June 2006 (UTC)
Citations are not required for obvious observations. Just look at scientific papers or technical articles on precision temperature measurement instrumentation. Check out the first paragraph of this article on SPRDTs 304 KB PDF. The scientific world abounds with this mixed use. It's hard to find a rational explanation for why this practice exists and a Wikipedia article on the kelvin is the perfect location for it. An article in Wikipedia can give the explanation that the BIPM's rule officially allowing the °C to be used to express an increment should have settled the issue and the scientific world is retarded (but I doubt that is a very satisfactory way of addressing the issue). Greg L 19:33, 14 June 2006 (UTC)
The imporant issue in science papers is the unambiguous communication of temperature values and uncertainties. See this NASA link which referrs to "An average liner metal temperature of 915 K, 355 kelvins greater than…" This is common practice in real-world science that is observed for a very good reason: it avoids confusion. The reasons underlying this practice should be explained even if it isn't sanctified by an international body. The very heading of this section ("Why technical articles use a mix of kelvin and Celsius scales") betrays its reason for existence: to simply explain why it is done this way. This is a community resource and you are free to contribute to this article. I hope you can make this section interesting, truthfull, and informative. If you think the whole section should be deleted, I can't stop you and don't have time to play "musical reverts" Greg L 22:53, 14 June 2006 (UTC)
Have you considered asking a Ph.D. chemist about the mixed use of °C and kelvins in scientific papers? Greg L 03:54, 15 June 2006 (UTC)
Please don't remove multiples, for consistency they are in all seven base SI units.
PLEASE GIVE THE HIGH VOLTAGE BETWEEN LOW VOLTAGE
I think this unit being named after Baron Kelvin should be mentioned earlier than it is now, perhaps even in the first sentence as it is with Celsius. I think finding out who a unit is named after is often important to readers. What do others think? -- Allen 06:19, 12 September 2006 (UTC)