# Degree of Celsius

 of these articles is concerned with the unit of the temperature. For other meanings of Celsius see Celsius (term clarifying).
Unit
standard SI-UNIT
name degrees Celsius
size of temperature
unit symbol °C
symbols [itex] \ vartheta< /math> (t, falsely T)
designated after Differently Celsius
derived from Kelvin

of the degrees Celsius (colloquially frequent, but wrongly: the degrees Celsius) is a unit of the temperature. The centigrade temperature scale was introduced 1742 by the Swedish astronomer differently Celsius, after which the unit was designated.The temperature degree celsius scale uses the temperatures of freezing and boiling point of the water as fixed points with normal print - D. h. with an air pressure of 1013,25 hPa; between them takes place a linear partitioning in 100 „degrees “parts mentioned, which also to thathistorical designation „Skale of the dog-RTT-hasty thermometer “led.

Differently Celsius designated the freezing point temperature with 100 °C and the boiling point temperature with 0 °C. Later the temperature levels of both fixed points were turned to the today common values.

Something other representation is in the standard DIN 1345 (edition December 1993) DIN. There a special size designation is introduced „temperature degree celsius “; it is therefore the difference of the respective thermodynamic temperature and the firm Bezugstemperatur 273.15 K. Because this standard for temperature differences the useKelvin recommends, specifies it further: „With indication of temperature degree celsius the name of units becomes degrees Celsius (unit symbol: °C) as special name for Kelvin uses.

The word „degrees “meant nothing else during the introduction, as today „unit “. In particularthe distance, divided around the liquid column from the melting point to the boiling point of water became larger in 100 “degrees” = “units”, there one lengths such as z. B. Meter not to use could, because different liquids have different linear extensions.

## symbols

as symbol for temperature degree celsius is [itex] \ vartheta< /math> (rarely also [itex] \ theta< /math>) (Theta) usually and standard. Falsely becomesin addition, T uses. According to DIN 1345 from December 1993 is also t symbol for temperature degree celsius. Actually T for the absolute temperature is reserved in Kelvin (demarcation forms t and indexation). Hereby the symbols for the temperature are meant, notfor instance a symbol for degrees Celsius.

## definition

a temperature (at a certain time in a certain point) remains the same also if the value in degrees Celsius, Kelvin or oneother temperature unit one indicates:

[itex] \ vartheta_ {\ rm degrees \, Celsius} = T_ {\ rm Kelvin}< /math>

To the numerical values on use of the units degrees Celsius and Kelvin here the equation applies:

[itex] \ left \ {\ vartheta_ {\ rm degree \, Celsius} \ right \} = \ left \ {T_ {\ rm Kelvin} \ right \} - 273 {,} 15 [/itex]

## temperature difference

the temperature difference [itex] \ delta \ vartheta< /math> the difference is in the temperature of two measuring points [itex] \ varphi \,< /math>, which differ in the time and/or spatial position. As unit for temperature differences becomes Kelvin (because of the SI system) of DINin the standard DIN 1345 (edition December 1993) recommended; however that grants to DIN there: „After the resolution of the 13. General conference for measure and weight (1967-1968) may be indicated the difference of two temperature degree celsius also in the unit degrees Celsius (°C). “In the sense of this standard „temperature degree celsius represents “the difference of the respective thermodynamic temperature and the firm Bezugstemperatur 273.15 K; with indication of temperature degree celsius the name of units degrees Celsius is used as special name for Kelvin. (For temperature differences recommendsthe standard actually Kelvin.)

## in the following

section some conversion tables for different temperature levels are indicated to conversion and - units.

### temperature scales

overview of the temperature scales
scale Kelvin Celsius Fahrenheit Rankine Delisle Newton Réaumur Rømer
Unit Kelvin degrees Celsius degree of Fahrenheit degree of Rankine degrees of Delisle degree Newton degree of Réaumur degrees of Rømer
unit symbol K °C °F °Ra, °R °De, °D °N °Ré, °Re °Rø
first fixed point F 1 T 0
= 0 K
T Schm (H2 O)
= 0 °C
winters in Danzig*
= 0 °F
T 0
= 0 °Ra
T simmer (H 2 O)
= 0 °De
T Schm (H 2 O)
= 0 °N
T Schm (H 2 O)
=0 °Ré
T Schm (H 2 O)
= 7.5 °Rø
second fixed point F 2 T t (H 2 O)
= 273.16 K
T simmer (H 2 O)
= 100 °C
T humans *
= 100 °F
- T Schm (H2 O)
= 150 °De
T simmer (H 2 O)
= 33 °N
T simmer (H 2 O)
= 80 °Ré
T simmer (H 2 O)
= 60 °Rø
Skalenintervall (F 2 −F 1)/273.16 (F 2 −Fto 1)/100 (F 2 −F 1)/96 see Fahrenheit (F 2 −F 1)/150 (F 2 −F 1)/33 (F 2 −F 1)/80 (F 2 −F 1)/100
inventors William Thomson („lord Kelvin “) differently Celsius Daniel Fahrenheit William Rankine Joseph Delisle Isaac Newton René Réaumur of oils Rømer
developing year 1848 1742 1724 1859 1732 ~ 1700 1730 1701
circulation area world-wide (SI-UNIT) world-wide the USA, Jamaica the USA Russia (19.Jhd.) - Western Europe to 19. Jhd. -

* the measured lowest temperature of the winter 1708/1709 was used in Danzig (−17,8 °C) and the Körpertemperatur, which actually measured Fahrenheit (37.8 °C).

### temperature conversion

conversion between temperature scales
after\ of absolute scale (C) centigrade temperature scale (°C) Réaumur scale (°Ré) Fahrenheit scale (°F)
T Kelvin = T K = T C + 273.15 = T · 1,25 + 273.15 = (T F + 459.67) ÷ 1.8
T Celsius = T K − 273.15 = T C = T · 1,25 = (T F − 32) ÷ 1.8
T Réaumur = (T K − 273,15) · 0,8 = T C · 0,8 = T = (T F − 32) ÷2.25
T Fahrenheit = T K · 1,8 − 459.67 = T C · 1,8 + 32 = T · 2,25 + 32 = T F
T Rankine = T K · 1,8 = T C· 1,8 +491,67 = T · 2,25 + 491.67 = T F + 459.67
T Rømer = (T K − 273,15) · 21/40 + 7.5 = T C · 21/40 + 7.5 = T · 21/32 + 7.5 = TF − 32) · 7/24 + 7.5
T Delisle = (373.15 − T K) · 1,5 = (100 − T C) · 1,5 = (80 − T) · 1,875 = (212 − T F) ·5/6
T Newton = (T K − 273,15) · 0,33 = T C · 0,33 = T · 0,4125 = (T F − 32) · 11/60
after \ of Rankine scale (°Ra) Rømer scale (°Rø) Delisle scale (°De) Newton scale (°N)
T Kelvin = T RA ÷ 1.8 = (T − 7,5) · 40/21 + 273.15 = 373.15 − T De · 2/3 = T N · 100/33 + 273.15
T Celsius = T RA ÷ 1.8 − 273.15 = (T− 7,5) · 40/21 = 100 − T De · 2/3 = T N · 100/33
T Réaumur = T RA ÷ 2.25 - 218.52 = (T − 7,5) · 32/21 = 80 − T De · 8/15 = T N · 80/33
T Fahrenheit = T RA − 459.67 = (T − 7,5) · 24/7 + 32 = 212 − T De · 1,2 = T N · 60/11 + 32
T Rankine = T RA = (T − 7,5) · 24/7 + 491.67 = 671.67 − T De · 1,2 = T N · 60/11 + 491.67
T Rømer = (T RA − 491,67) · 7/24 + 7.5 = T = 60 −T De · 0,35 = T N · 35/22 + 7.5
T Delisle = (671.67 − T RA) · 5/6 = (60 − T) · 20/7 = T De = (33 − T N) ÷ 0,22
T Newton = (T RA − 491,67) · 11/60 = (T − 7,5) · 22/35 = 33 − T De · 0,22 = T N

### temperature comparison

some temperature levels in the different scales
measured value \ scale Fahrenheit Rankine Réaumur Celsius Kelvin
middle surface temperature of the sun 10,430 °F 10,890 °Ra 4,622 °R 5,777 °C 6,050 K
melting point of iron 2,795 °F 3,255 °Ra 1,228 °R 1,535 °C 1,808K
melting point of lead 621.43 °F 1081.10 °Ra 261.97 °R 327.46 °C 600.61 K
boiling point of water 212 °F 671.67 °Ra 80 °R 100 °C 373.15 K
highest air temperature 136.04 °F 595.71 °Ra 46.24 °R 57.80 measured in the free one °C 330.95 K
Körpertemperatur of humans after Fahrenheit 100 °F 559.67 °Ra 30.22 °R 37.78 °C 310.93 K
freezing point of water 32 °F 491.67 °Ra 0 °R 0 °C 273.15 K
lowest temperature in Danzig, winter 1708/09 0 °F 459.67 °Ra −14,22 °R −17,78 °C 255.37 K
melting point of mercury −37,89 °F 421.78 °Ra −31,06 °R −38,83 °C 234.32 K
deepest air temperature −130,90 measured in the free one °F 328.77 °Ra −72,40 °R −90,50 °C 182.65 K
freezing point of alcohol −173,92 °F to 285,75 °Ra −91,52 °R −114,40 °C 158.75 K
boiling point of nitrogen −320,44 °F 139.23 °Ra −156,64 °R −195,80 °C 77.35 K
absolute zero −459,67 °F 0 °Ra −218,52 °R −273,15 °C 0 K