Temperaturskala

Ein temperaturskala er ein måte å dele eit termometer inn i grader på. Grunneininga for temperaturmåling er kelvin og er definert ut frå termodynamisk temperatur, og andre temperaturskalaer er fastlagt i tilhøve til kelvinskalaen.

Forskjellige temperaturskalaer

Formalar for temperaturomrekning

Samanlikning	absolutt null	vatn frys	kroppstemp.	vatn kokar
Kelvin	0 K	273,15 K	310,15 K	373,15 K
Celsius	−273,15 °C	0 °C	37 °C	100 °C
Fahrenheit	−459,67 °F	32 °F	98,6 °F	212 °F
Rankine	0 °Ra	491,67 °Ra	558,27 °Ra	671,67 °Ra
Delisle	559,73 °De	150 °De	94,5 °De	0 °De
Newton	−90,14 °N	0 °N	12,21 °N	33 °N
Réaumur	−218,52 °Ré	0 °Ré	29,6 °Ré	80 °Ré
Rømer	−135,9 °Rø	7,5 °Rø	26,93 °Rø	60 °Rø

Kelvin

Celsius	[°C] = [K] − 273,15	[K] = [°C] + 273,15
Fahrenheit	[°F] = [K] · 9/5 − 459,67	[K] = ([°F] + 459,67) · 5/9
Rankine	[°Ra] = [K] · 9/5	[K] = [°Ra] · 5/9
Réaumur	[°Ré] = ([K] − 273,15) · 4/5	[K] = [°Ré] · 5/4 + 273,15
Newton	[°N] = ([K] − 273,15) · 33/100	[K] = [°N] · 100/33 + 273,15
Rømer	[°Rø] = ([K] − 273,15) · 21/40 + 7,5	[K] = ([°Rø] − 7,5) · 40/21 + 273,15
Delisle	[°De] = (373,15 − [K]) · 3/2	[K] = 373,15 − [°De] · 2/3

Matematisk oppstilte formlar:

$K={}^{\circ }\!C-273,15={\frac {5({}^{\circ }\!F+459,67)}{9}}={\frac {5^{\circ }\!Ra}{9}}={\frac {5^{\circ }\!R{\acute {e}}}{4}}+273,15$

$K={\frac {100^{\circ }\!N}{33}}+273,15={\frac {40({}^{\circ }\!R{\ddot {o}}-7,5)}{21}}+273,15=373,15-{\frac {2^{\circ }\!De}{3}}$

Celsius

Kelvin	[K] = [°C] + 273,15	[°C] = [K] − 273,15
Fahrenheit	[°F] = [°C] · 9/5 + 32	[°C] = ([°F] − 32) · 5/9
Rankine	[°Ra] = [°C] · 9/5 + 491,67	[°C] = ([°Ra] − 491,67) · 5/9
Réaumur	[°Ré] = [°C] · 4/5	[°C] = [°Ré] · 5/4
Newton	[°N] = [°C] · 33/100	[°C] = [°N] · 100/33
Rømer	[°Rø] = [°C] · 21/40 + 7,5	[°C] = ([°Rø] − 7,5) · 40/21
Delisle	[°De] = (100 − [°C]) · 3/2	[°C] = 100 − [°De] · 2/3

Matematisk oppstilte formlar:

${}^{\circ }\!C=K-273,15={\frac {5({}^{\circ }\!F-32)}{9}}={\frac {5(Ra-491,67)}{9}}$

${}^{\circ }\!C={\frac {5^{\circ }\!R{\acute {e}}}{4}}={\frac {100^{\circ }\!N}{33}}={\frac {40({}^{\circ }\!R{\ddot {o}}-7,5)}{21}}={\frac {2^{\circ }\!De}{3}}-100$

Fahrenheit

Kelvin	[K] = ([°F] + 459,67) · 5/9	[°F] = [K] · 9/5 − 459,67
Celsius	[°C] = ([°F] − 32) · 5/9	[°F] = [°C] · 9/5 + 32
Rankine	[°Ra] = [°F] + 459,67	[°F] = [°Ra] − 459,67
Réaumur	[°Ré] = ([°F] − 32) · 4/9	[°F] = [°Ré] · 9/4 + 32
Newton	[°N] = ([°F] − 32) · 11/60	[°F] = [°N] · 60/11 + 32
Rømer	[°Rø] = ([°F] − 32) · 7/24 + 7,5	[°F] = ([°Rø] − 7,5) · 24/7 + 32
Delisle	[°De] = (212 − [°F]) · 5/6	[°F] = 212 − [°De] · 6/5

Matematisk oppstilte formlar:

${}^{\circ }\!F={\frac {9K}{5}}-459,67={\frac {9{}^{\circ }\!C}{5}}+32={}^{\circ }\!Ra-459,67={\frac {45^{\circ }\!R{\acute {e}}/4-273,15}{5}}$

${}^{\circ }\!F={\frac {60^{\circ }\!N}{11}}+32={\frac {24({}^{\circ }\!R{\ddot {o}}-7,5)}{7}}+32=212-{\frac {6De}{5}}$

Rankine

Kelvin	[K] = [°R] · 5/9	[°R] = [K] · 9/5
Celsius	[°C] = [°R] · 5/9 − 273,15	[°R] = ([°C] + 273,15) · 9/5
Fahrenheit	[°F] = [°R] − 459,67	[°R] = [°F] + 459,67
Réaumur	[°Ré] = ([°R] · 5/9 + 273,15) · 4/5	[°R] = ([°Ré] · 5/4 − 273,15) · 9/5
Newton	[°N] = ([°R] − 491,67) · 11/60	[°R] = [°N] · 60/11 + 491,67
Rømer	[°Rø] = ([°R] − 491,67) · 7/24 + 7,5	[°R] = ([°Rø] − 7,5) · 24/7 + 491,67
Delisle	[°De] = (671,67 − [°R]) · 5/6	[°R] = 671,67 − [°De] · 6/5

Matematisk oppstilte formlar:

${}^{\circ }\!R={\frac {9K}{5}}={\frac {9({}^{\circ }\!C+273,15)}{5}}={}^{\circ }\!F+459,67={\frac {9(5^{\circ }\!R{\acute {e}}/5-273,15)}{5}}$

${}^{\circ }\!R={\frac {60^{\circ }\!N}{11}}+491,67={\frac {24({}^{\circ }\!R{\ddot {o}}-7,5)}{7}}+491,67=671,67-{\frac {6^{\circ }\!De}{5}}$

Delisle

Kelvin	[K] = 373,15 − [°De] · 2/3	[°De] = (373,15 − [K]) · 3/2
Celsius	[°C] = 100 − [°De] · 2/3	[°De] = (100 − [°C]) · 3/2
Fahrenheit	[°F] = 212 − [°De] · 6/5	[°De] = (212 − [°F]) · 5/6
Rankine	[°Ra] = 671,67 − [°De] · 6/5	[°De] = (671,67 − [°Ra]) · 5/6
Réaumur	[°Ré] = 80 − [°De] · 8/15	[°De] = (80 − [°Ré]) · 15/8
Newton	[°N] = 33 − [°De] · 11/50	[°De] = (33 − [°N]) · 50/11
Rømer	[°Rø] = 60 − [°De] · 7/20	[°De] = (60 − [°Rø]) · 20/7

Matematisk oppstilte formlar:

${}^{\circ }\!De={\frac {3(373,15-K)}{2}}={\frac {3(100-{}^{\circ }\!C)}{2}}={\frac {5(212-{}^{\circ }\!F)}{6}}$

${}^{\circ }\!De={\frac {5(671,67-{}^{\circ }\!Ra)}{6}}={\frac {15(80-^{\circ }\!R{\acute {e}})}{8}}={\frac {50(33-{}^{\circ }\!N)}{11}}={\frac {20(60-{}^{\circ }\!R{\ddot {o}}\!)}{7}}$

Newton

Kelvin	[K] = [°N] · 100/33 + 273,15	[°N] = ([K] − 273,15) · 33/100
Celsius	[°C] = [°N] · 100/33	[°N] = [°C] · 33/100
Fahrenheit	[°F] = [°N] · 60/11 + 32	[°N] = ([°F] − 32) · 11/60
Rankine	[°Ra] = [°N] · 60/11 + 491,67	[°N] = ([°Ra] − 491,67) · 11/60
Réaumur	[°Ré] = [°N] · 80/33	[°N] = [°Ré] · 33/80
Rømer	[°Rø] = [°N] · 35/22 + 7,5	[°N] = ([°Rø] − 7,5) · 22/35
Delisle	[°De] = (33 − [°N]) · 50/11	[°N] = 33 − [°De] · 11/50

Matematisk oppstilte formlar:

${}^{\circ }\!N={\frac {33(K-273,15)}{100}}={\frac {33^{\circ }\!C}{100}}={\frac {11({}^{\circ }\!F-32)}{60}}$

${}^{\circ }\!N={\frac {11({}^{\circ }\!Ra-491,67)}{60}}={\frac {33^{\circ }\!R{\acute {e}}}{80}}={\frac {22(R{\ddot {o}}-7,5)}{35}}=33-{\frac {11{}^{\circ }\!De}{50}}$

Réaumur

Kelvin	[K] = [°Ré] · 5/4 + 273,15	[°Ré] = ([K] − 273,15) · 4/5
Celsius	[°C] = [°Ré] · 5/4	[°Ré] = [°C] · 4/5
Fahrenheit	[°F] = [°Ré] · 9/4 + 32	[°Ré] = ([°F] − 32) · 4/9
Rankine	[°Ra] = [°Ré] · 9/4 + 491,67	[°Ré] = ([°Ra] − 491,67) · 4/9
Newton	[°N] = [°Ré] · 33/80	[°Ré] = [°N] · 80/33
Rømer	[°Rø] = [°Ré] · 21/32 + 7,5	[°Ré] = ([°Rø] − 7,5) · 32/21
Delisle	[°De] = (80 − [°Ré]) · 15/8	[°Ré] = 80 − [°De] · 8/15

Matematisk oppstilte formlar:

${}^{\circ }\!R{\acute {e}}={\frac {4(K-273,15)}{5}}={\frac {4{}^{\circ }\!C}{5}}={\frac {4({}^{\circ }\!F-32)}{9}}$

${}^{\circ }\!R{\acute {e}}={\frac {4({}^{\circ }\!Ra-491,67)}{9}}={\frac {80^{\circ }\!N}{33}}={\frac {32({}^{\circ }\!R{\ddot {o}}-7,5)}{21}}=80-{\frac {8^{\circ }\!De}{15}}$

Rømer

Kelvin	[K] = ([°Rø] − 7,5) · 40/21 + 273,15	[°Rø] = ([K] − 273,15) · 21/40 + 7,5
Celsius	[°C] = ([°Rø] − 7,5) · 40/21	[°Rø] = [°C] · 21/40 + 7,5
Fahrenheit	[°F] = ([°Rø] − 7,5) · 24/7 + 32	[°Rø] = ([°F] − 32) · 7/24 + 7,5
Rankine	[°Ra] = ([°Rø] − 7,5) · 24/7 + 491,67	[°Rø] = ([°Ra] − 491,67) · 7/24 + 7,5
Réaumur	[°Ré] = ([°Rø] − 7,5) · 32/21	[°Rø] = [°Ré] · 21/32 + 7,5
Newton	[°N] = ([°Rø] − 7,5) · 22/35	[°Rø] = [°N] · 35/22 + 7,5
Delisle	[°De] = (60 − [°Rø]) · 20/7	[°Rø] = 60 − [°De] · 7/20

Matematisk oppstilte formlar:

${}^{\circ }\!R{\ddot {o}}={\frac {21(K-273,15)}{40}}+7,5={\frac {21^{\circ }\!C}{40}}+7,5={\frac {7({}^{\circ }\!F-32)}{24}}+7,5$

${}^{\circ }\!R{\ddot {o}}={\frac {7({}^{\circ }\!Ra-491,67)}{24}}+7,5={\frac {21^{\circ }\!R{\acute {e}}}{32}}+7,5={\frac {35^{\circ }\!N}{22}}+7,5=60-{\frac {7^{\circ }\!De}{20}}$

Bakgrunnsstoff

• Temperaturomrekning på nettet Arkivert 2005-12-11 ved Wayback Machine.

Kjelder

• Holtebekk, Trygve. (2009, 15. februar). Temperaturskala. I Store norske leksikon. Henta 16. november 2013 frå http://snl.no/temperaturskala.