"केल्विन" (अनुभाग) सम्पादित करें

== कैल्विन की परिभाषा ==
[[File:CelsiusKelvinThermometer.jpg|thumb|200px|]]
कैल्विन और कैल्विन पैमाना, अन्तर्राष्ट्रीय समझौते के अनुसार दो बिंदुओं द्वारा परिभाषित हैं: [[:en:Vienna Standard Mean Ocean Water|वियना मानक औसत महासागरीय जल]] (VSMOW) के [[विशुद्ध बिंदु]] और [[त्रिगुण बिंदु]].<ref name=sib2115>{{cite web | title=Unit of thermodynamic temperature (kelvin) | work=SI Brochure, 8th edition | pages=Section 2.1.1.5 | url=http://www1.bipm.org/en/si/si_brochure/chapter2/2-1/2-1-1/kelvin.html | publisher=Bureau International des Poids et Mesures | date=1967 | accessdate=2008-02-06 | archive-url=https://web.archive.org/web/20070926215600/http://www1.bipm.org/en/si/si_brochure/chapter2/2-1/2-1-1/kelvin.html | archive-date=26 सितंबर 2007 | url-status=dead }}</ref> यह परिभाषा कैल्विन पैमाने को सीधे सेल्सियस पैमाने से जोड़ती है। 
विशुद्ध शून्य: इसे परम शून्य भी कहते हैं। वह तापमान, जिससे अधिक शीतल कुछ भी संभव नहीं होता और वस्तु में कुछ भी ऊर्जा नहीं शेष रहती है। — यह परिभाषा अनुसार 0 K ''और'' −273.15&nbsp;°C है। 
जल का [[त्रिगुण बिंदु]] परिभाषा अनुसार, यथार्थतः 273.16 K ''और'' 0.01&nbsp;°C होता है। इस परिभाषा से तीन कार्य होते है:
# यह कैल्विन इकाई की महत्ता स्थिर करता है, जो कि 273.16 के परम शून्य और जल के त्रिगुण बिंदु के अन्तर का एक भाग होता है;
# यह स्थापित करता है, कि एक कैल्विन की महत्ता यथार्थतः सेल्सियस पैमाने की एक डिग्री बढ़ोत्तरी के बराबर हो; और
# यह दोनों पैमानों के नल बिंदुओं के अन्तर को 273.15 kelvins (0 K ≡ −273.15&nbsp;°C और 273.16 K ≡ 0.01&nbsp;°C) के बराबर रखता है। कैल्विन में तापमान को अन्य पैमानों में निम्न सारणी द्वारा अंतरण किया जासकता है।

=== कैल्विन के तुल्य ===

{| border="1" cellpadding="4" cellspacing="0" style="margin: 1em 1em 1em 0; background: #f5f5f0; border: 2px #52524d solid; border-collapse: collapse; font-size: 95%;"
|-
|style="background:#d4d4d4" align="center"|''' '''
|style="background:#d4d4d4" align="center"|'''कैल्विन'''
|style="background:#d4d4d4" align="center"|'''सेल्सियस'''
|style="background:#d4d4d4" align="center"|'''फ़ैरन्हाइट'''
|-
|style="background:#d9d9d3" align="right"|परम शून्य<br />
(exactly, परिभाषा अनुसार)
|align="center"|0 K
|align="center"|−273.15&nbsp;°C
|align="center"|−459.67&nbsp;°F
|-
|style="background:#d9d9d3" align="right"|जल का हिमांक बिंदु
|align="center"|273.15 K
|align="center"|0&nbsp;°C
|align="center"|32&nbsp;°F
|-
|style="background:#d9d9d3" align="right"|जल का त्रिगुण बिंदु<br />
(exactly, by definition)
|align="center"|273.16 K
|align="center"|0.01&nbsp;°C
|align="center"|32.018&nbsp;°F
|-
|style="background:#d9d9d3" align="right"|जल का [[क्वथनांक]]
|align="center"|373.1339 K
|align="center"|[[सेल्सियस#जल के हिमांक और क्वथानांक|99.9839 °C]]
|align="center"|211.9710&nbsp;°F
|}

<!-- For [[Vienna Standard Mean Ocean Water]] (VSMOW) at one [[Atmosphere (unit)|standard atmosphere]] (101.325 kPa) when calibrated solely per the two-point definition of thermodynamic temperature. Older definitions of the Celsius scale once defined the boiling point of water under one standard atmosphere as being exactly 100 °C. However, the current definition results in a boiling point that is actually 16.1 mK less. For more about the actual boiling point of water, see [[Vienna Standard Mean Ocean Water#VSMOW in temperature measurement|VSMOW in temperature measurement]]. -->

=== SI उपसर्ग === <!-- This section is linked from [[Absolute zero]], [[Thermodynamic temperature]], as well as from other articles. Only delete or rename it with careful consideration, and please fix any resulting broken links.-->

{{SI गुणक|unit=केल्विन|symbol=K}}

<!-- == Typographical and usage conventions ==
===Uppercase/lowercase, plural form usage, and written conventions===
When reference is made to the unit kelvin (either a specific temperature or a temperature interval), kelvin is always spelled with a lowercase k unless it is the first word in a sentence.<ref>BIPM: SI brochure, [http://www1.bipm.org/en/si/si_brochure/chapter5/5-2.html Section&nbsp;5.2]</ref> When reference is made to the "Kelvin ''scale''", the word "kelvin"—which is normally a noun—functions [[adjective|adjectivally]] to modify the noun "scale" and is capitalized.

Until the 13th [[General Conference on Weights and Measures]] (CGPM) in 1967–1968, the unit kelvin was called a "degree", the same as with the other temperature scales at the time. It was distinguished from the other scales with either the adjective suffix "Kelvin" ("degree Kelvin") or with "absolute" ("degree absolute") and its symbol was °K. Note that the latter (degree absolute), which was the unit’s official name from 1948 until 1954, was rather ambiguous since it could also be interpreted as referring to the [[Rankine scale]]. Before the 13th CGPM, the plural forms were "degrees Kelvin" or "degrees absolute". The 13th CGPM changed the name to simply "kelvin" (symbol K).<ref>{{cite paper | author=Barry N. Taylor | title=Guide for the Use of the International System of Units (SI) | version=Special Publication 811 | format=.PDF | publisher=National Institute of Standards and Technology | url=http://physics.nist.gov/cuu/pdf/sp811.pdf | date=1995 | accessdate=2008-02-06}}</ref> The omission of "degree" indicates that it is not relative to an arbitrary reference point such as the Celsius and Fahrenheit scales, but rather an absolute unit of measure which can be manipulated algebraically (e.g. multiply by two to indicate twice the amount of heat). -->

=== तापमान और अंतराल ===
<!-- Because the kelvin is an individual unit of measure, it is particularly well-suited for expressing ''temperature intervals:'' differences between temperatures or their uncertainties (e.g., “Agar exhibited a melting point hysteresis of 25 kelvins.” and “The uncertainty was 10 millikelvins.”). Of course, the kelvin is also used to express specific temperatures along its scale (e.g. “[[Gallium]] melts at 302.9146 kelvin”).

One disadvantage of the kelvin is that intervals ''and'' specific temperatures on the Kelvin scale use exactly the same symbol (e.g., “Agar exhibited a melting point hysteresis of 25 K,” and “The triple point of hydrogen is 13.8033 K”). -->

<!-- ===Formatting and typestyle for the K symbol===
The kelvin symbol is always a [[Roman type|roman]], [[Italic type|non-italic]] capital K. In the SI naming convention, all symbols named after a person are capitalized; in the case of the kelvin, capitalizing also distinguishes the symbol from the SI prefix “kilo”, which has the lowercase k as its symbol. The admonition against italicizing the symbol K applies to all SI unit symbols; only symbols for variables and constants (e.g. ''P'' = pressure, and ''c'' = 299,792,458 m/s) are italicized in scientific and engineering papers. As with most other SI unit symbols (angle symbols, e.g. 45° 3′ 4″, are the exception) there is a space between the numeric value and the kelvin symbol (e.g. “99.987 K”).<ref name=nist>{{cite web | title=SI Unit rules and style conventions | url=http://physics.nist.gov/cuu/Units/checklist.html | publisher=National Institute of Standards and Technology | date=September 2004 | accessdate=2008-02-06}}</ref><ref name=sib533>{{cite web | title=Rules and style conventions for expressing values of quantities | work=SI Brochure, 8th edition | pages=Section 5.3.3 | url=http://www.bipm.org/en/si/si_brochure/chapter5/5-3-2.html#5-3-3 | publisher=Bureau International des Poids et Mesures | date=1967 | accessdate=2008-02-06}}</ref>

===The special Unicode kelvin character===
[[Unicode]] provides a [[Unicode compatibility characters|compatibility character]] for the kelvin at U+212A (decimal 8490), for compatibility with CJK encodings that provide such a character (as such, in most fonts the width is the same as for [[fullwidth]] characters). Below in maroon text is the kelvin character followed immediately by a simple uppercase K:

:<span class="Unicode" style="color:#721F01;font-size:bigger">K K</span>

When viewed on computers that properly support Unicode, the above line may be similar to the line below (size may vary): -->

:[[चित्र:Kelvin symbol plus K.svg|23px]]
<!-- 
The canonical decomposition of this character is U+004B (uppercase K), so some browsers may simply display a "K" in its place due to [[Unicode normalization]].-->

=== कैल्विन और सेल्सियस पैमानों का तकनीकी लेखों में मिश्रित प्रयोग ===
<!-- In science and in engineering, the Celsius scale and the kelvin are often used simultaneously in the same article (e.g. “…its measured value was 0.01023 °C with an uncertainty of 70 µK…”). This practice is permissible because the degree Celsius is a special name for the kelvin for use in expressing Celsius temperatures and the magnitude of the degree Celsius is exactly equal to that of the kelvin.<ref name=sib222>{{cite web | title=Units with special names and symbols; units that incorporate special names and symbols | work=SI Brochure, 8th edition | pages=Section 2.2.2, Table 3 | url=http://www.bipm.org/en/si/si_brochure/chapter2/2-2/table3.html | publisher=Bureau International des Poids et Mesures | date=2006 | accessdate=2008-02-06}}</ref> Notwithstanding the official endorsement provided by Resolution 3 of the 13th CGPM, states “a temperature interval may also be expressed in degrees Celsius,” the practice of simultaneously using both “°C” and “K” remains widespread throughout the scientific world as the use of [[SI prefix#List of SI prefixes|SI prefixed]] forms of the degree Celsius (such as “µ°C” or “microdegrees Celsius”) to express a temperature interval has not been well-adopted.<ref name=res313>{{cite web | title=Resolution 3: SI unit of thermodynamic temperature (kelvin) | work=Resolutions of the 13th CGPM | url=http://www.bipm.fr/en/CGPM/db/13/3/ | publisher=Bureau International des Poids et Mesures | date=1967 | accessdate=2008-02-06}}</ref> -->