Celcius to Farenheit Conversion

Temperature Conversion

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Fun Temperature Facts

Farenheit Celcius Kelvin What happens?
212 100 373.15 boiling point of water
174.2 79 352.15 boiling point of alcohol (ethanol)
134 56.67 329.82 the record high temperature in California
97.88 36.6 309.75 normal human body temperature
86 30 303.15 hot day - perfect for the beach
69 20 293.15 ideal winter thermostat temperature
0 273.15 freezing point of water
0 -17.78 255.37 very cold - you better stay inside
-40 -40 233.15 the record low temperature in Arizona
-320.42 -195.79 77.36 boiling point of nitrogen
-452.11 -268.95 4.2 boiling point of helium
-459.67 -273.15 0 absolute zero

How To Convert Between Celcius and Farenheit:

  Farenheit to Celcius  
  1. Subtract 32 from degrees Farenheit
  2. Multiply by 5
  3. Divide by 9
  Celcius to Farenheit  
  1. Multiply degrees Celcius by 9
  2. Divide by 5
  3. Add 32

Temperature Measurement History

One of the earliest practical thermometers created in 1701 by Ole Christensen Romer, (also responsible for measuring the speed of light in 1676), used red wine as a temperature indicator. 0 symbolized the temperature of a mixture of ice and salt, which was roughly around 259 K, and the freezing point of water (273.1 K) was represented by the number 7 ˝. In Romer’s temperature scale, the boiling point of water (373.15 K) was represented by 60.

The mercury thermometer was created by Daniel Gabriel Fahrenheit (1686 – 1736) in 1714. Fahrenheit, who was committed towards creation of precision meteorological instruments, was also responsible for the invention of the effect of pressure on the boiling point of liquids.

In the practical temperature scale created by Fahrenheit, 0 was synonymous with the coldest temperature related to Western Europe while 100 denoted the maximum temperature.  Although his initial creation had a scale in which 0 denoted the temperature of a mixture of salt and ice (255 K), 30 symbolized freezing point of water (273.15 K) and the mean human body temperature (310 K) was denoted by 90, he later corrected the freezing point and boiling point of water to 32 and 212 respectively. Most countries including the United States make use of the Fahrenheit scale to measure temperature.

Rene Antoine Ferchault de Reamur (1683 – 1757) invented a temperature scale considered to be much more simple in 1731. Much popular in France, the freezing point of water was denoted by 0 (273.15 K) while the boiling point was symbolized by 80 (373.15 K).

It was in 1742 that the centigrade temperature scale was invented by Anders Celsius (1701 – 1744). He made use of 0 and 100 to denote the boiling point (373.15 K) and the freezing point (273.15 K) of water respectively. 

The centigrade relative temperature scale was created by Carl Linnaeus (1707 – 1778) by reversing the scale created by Anders Celsius. Thereby, the freezing point of water was changed to 0 (273.15 K) and the boiling point to 100 (373.15 K).  This particular temperature scale later attained immense popularity and is named as the ‘degree centigrade’ with a symbol of ‘°C’.

A thermodynamic temperature scale which used the degree centigrade scale as its primary unit and in which 0 was designated with thermodynamic absolute zero was projected by William Thomson (1824 – 1907). Named as the Kelvin thermodynamic temperature scale, it was accorded the title of ‘degree Kelvin’ with a symbol of ‘°K’.

Another thermodynamic temperature scale which allocated 0 to the thermodynamic absolute zero was created by William John Macquorn Rankine (1820 – 1872) in 1859. But the base unit of his scale comprised of the degree Fahrenheit, and was accordingly termed Rankine thermodynamic temperature scale (degree Rankine) ‘°R’.

The 9th General Conference on Weights and Measures honored Anders Celsius by altering “degree centigrade” to “degree Celsius” in 1948.

Sir William Thomson, Baron Kelvin of Largs, Lord Kelvin of Scotland was honored in 1954 at the 10th General Conference on Weights and Measures by according the degree Kelvin as the metric unit of thermodynamic temperature. Accordingly, it assigned an exact value of 273.16 degree Kelvin to the triple point of water, which denotes a more accurate reference than the boiling or freezing point. The triple point of any substance is the thermodynamic state in which the state of matter whether solid, liquid, or gas, might exist together in thermodynamic equilibrium.

It was in 1967 at the 13th General Conference on Weights and Measures that the thermodynamic temperature unit degree Kelvin ‘°K’ was altered to ‘Kelvin’ with a symbol of ‘K’. This led to a redefinition of the Celsius temperature as the thermodynamic temperature minus 273.15 Kelvin.