This web site provides a method used for displaying temperatures in five different temperature scales.
People in the U.S. are the most familiar with the Fahrenheit scale, which is based on the freezing and boiling points of water. In this scale, water freezes at 32°F and boils at 212°F. The scale was established by the German-Dutch physicist Gabriel Daniel Fahrenheit in 1724.
The next most common scale is probably the Celcius (aka Centegrade) scale, also based on freezing and boiling points of water. In this scale, water freezes at 0°C and boils at 100°C. The 100-degree range is the reason for the original name "centigrade", with "centi" meaning "one hundred". This scale is named for the Swedish astronomer Anders Celsius , who established it in 1742. William Thomson Kelvin used it as the basis of his absolute temperature scale (see next).
Next-most common would be the Kelvin scale. This method is based on the point at which all molecular motion stops, and treats this point as the "absolute zero" point. This scale is primarily used in the empirical sciences. In this scale, water freezes at 273.15°K and boils at 373.15°K. As can be seen, this scale has the same-size degree change as the Celsius scale. When writing temperatures in the Kelvin scale, it is the convention to omit the degree symbol and merely use the letter K. This scale is named after the British mathematician and physicist William Thomson Kelvin, who proposed its use in 1848.
The last two scales are not used very often today. They are the Rankin scale and the Réaumur scale. The Rankin scale is similar to Kelvin, in that it is based on absolute zero; however, in this case the size of each degree is the same as the Fahrenheit scale, making the freezing point of water 491.67°R and the boiling point 671.67°R. This temperature scale is named after the Scottish engineer and physicist William John Macquorn Rankine , who proposed it in 1859.
The Réaumur scale is based on freezing and boiling of water, similar to the Celcius scale. However, this method is based on an 80° range, making the two points 0°r and 80°r, respectively. The Réaumur temperature scale is named after the French scientist René Antoine Ferchault de Réaumur, who proposed it in 1731.
The following table provides some comparisons of common values in these different scales.
| Temperature | Fahrenheit | Celsius | Kelvin | Rankine | Réaumur |
|---|---|---|---|---|---|
| Water freezes | 32 | 0 | 273.15 | 491.67 | 0 |
| Water boils | 212 | 100 | 373.15 | 671.67 | 80 |
| Absolute zero | -459.67 | -273.15 | 0 | 0 | -218.52 |
| Moderate oven | 325 | 162.77 | 435.93 | 784.67 | 130.22 |
| Normal Human Body | 98.6 | 37.0 | 310.15 | 558.27 | 29.6 |
| Desert Daytime Heat | 120.0 | 48.88 | 322.04 | 579.67 | 39.11 |
| Paper Catches Fire | 451.0 | 232.78 | 505.93 | 910.67 | 186.22 |
Version 1.0.0 26-Aug-2005
Copyright (c) Loyola Marymount University, 2005. All rights reserved.
This program may be freely copied and distributed under the conditions of the Gnu Public License (GPL). Please visit http://www.gnu.org/licenses/gpl.html to obtain a copy of the Gnu Public License, and read the details.
NOTE: The Java applet on the main page of this site, along with the HTML pages to display and operate the site, is an original work by B.J. Johnson of Loyola Marymount University, for use with the CMSI 401 Senior Software Engineering Lab and the CMSI 402 Senior Project Laboratory courses. The algorithms and methods involved are well-known and coincidentally bear similarity to other items which perform similar functions. Every effort has been made NOT to copy or plagiarize. If you feel that there are issues in this regard, or if there are computational errors that need to be corrected, please contact me at your earliest convenience at the following email address.
Contact: rjohns19@lmu.edu