SI Units: Temperature
The Kelvin (K) is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. The temperature 0 K is commonly referred to as "absolute zero." On the widely used Celsius temperature scale, water freezes at 0 °C and boils at about 100 °C. One Celsius degree is an interval of 1 K, and zero degrees Celsius if 273.15 K. An interval of one Celsius degree corresponds to an interval of 1.8 Fahrenheit degrees on the Fahrenheit temperature scale.
The standard temperature at the triple point of water is provided by a special cell, an evacuated glass cylinder containing pure water. When the cell is cooled enough so that a mantle of ice forms around the reentrant well, the temperature at the interface of solid, liquid, and vapor is 273.16 K. Thermometers to be calibrated are placed in the reentrant well.
Temperature Conversion (Exact)
|
| From |
To Fahrenheit |
To Celsius |
To Kelvin |
|
Fahrenheit (°F)
|
F
|
(F - 32) * 5/9
|
(F - 32) * 5/9
+ 273.15
|
|
Celsius (°C)
|
(C * 9/5) + 32
|
C
|
C + 273.15
|
|
Kelvin (K)
|
(K - 273.15) * 9/5 + 32
|
K - 273.15
|
K
|
|
Common Temperature Reference Points
|
| |
Celsius (°C) |
Kelvin |
Fahrenheit (°F) |
| Surface of the Sun |
5600
|
5900
|
101002
|
| Boiling Point of Water |
100
|
373
|
212
|
| Body Temperature |
37
|
310.2
|
98.6
|
| Sweltering Day |
40
|
313
|
104
|
| Hot Day |
30
|
303
|
86
|
| Room Temperature |
20
|
293
|
68
|
| Cold Day |
10
|
283
|
50
|
| Freezing Point of Water |
0
|
273
|
32
|
| Oven Temperature Equivalencies |
|
Description
|
°F
|
°C
|
|
Cool
|
200
|
90
|
|
Very Slow
|
250
|
120
|
|
Slow
|
300-325
|
150-160
|
|
Moderately Slow
|
325-350
|
160-180
|
|
Moderate
|
350-375
|
180-190
|
|
Moderately Hot
|
375-400
|
190-200
|
|
Hot
|
400-450
|
200-230
|
|
Very Hot
|
450-500
|
230-260
|
Celsius Temperature Poem
|
30 °C is hot |
20 °C is nice |
10 °C is cold |
0 °C is ice |
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