General Chat

Celsius was named after the Swedish astronomer Anders Celsius (1700's). One reason for the change was that the term centigrade was in use in continental Europe as a measure of plane angle equal to one ten-thousandth part of a right angle.

All I know is how to convert C to F and vice versa. And that there is (or was) also a Kelvin scale. Will have to get out my ancient (1950s) school science books to see what they say. Helens conversion formulae are correct.

To quote from Basic Physics Vol 1 Part 2, In the original scale as devised by Celsius, in 1742, the freezing pont of water was designated 100deg and its boiling point 0deg. On th Fahrenheit scale, named after its originator who devised it in 1709, the lower fixed point (the ice point) is marked 32degF and the upper fixed point (the steam point) 212degF. On the Centigrade scale, another one in common use, the lower fixed point is marked 0degC and the upper one 100degC. At the 9th General Conf. on Weights and Measures (and international meeting held in Oct 1948) it was agreed to change the name of this scale from Centigrade to Celsius thus bringing English-speaking countries into line with the many already using this term. However, there appears to be some reluctance to make the change and the Brit. Standards Institution has decided not to adopt the new name at this stage (c1950). Perhaps the EU decreed that Britain should follow suit.

double the temperature and add 30

Some wonderful answers there.but still not what I was looking for, .......we in britain used Fahrenheit as our preferred scale and when britain tried to go decimal with temperatures, Centigrade was the decimal scale. Fahrenheit copes with minus temperatures by going towards zero.......from freezing at 32 deg. ie 10 degrees of frost..=22 deg.F Centigrade does ONLY from freezing point UP to boiling, 0-100 degrees. therefore you cannot have -C temps The Celcius scale does go below zero............. perhaps some one will shoot me down, but that is how I understood it......Bob

Bob Well, what system do they use in places where the temperature regularly drops below freezing - ie Siberia, Iceland, etc??

It seems you can have minus centigrade temperatures: '1391/ Oxygen becomes a liquid if cooled to below *****minus 183 degrees centigrade***** (minus 297 F). The resulting liquid is pale blue. Cool it still further, to minus 218 degrees centigrade (minus 361 F), and it becomes a bright red solid.' www.firstscience*com/SITE/factfile/factfile1381_1400.asp

Helen, as I see it, the Centigrade scale IS zero to 100degrees. of course there are 'calculated' minus C temps. Electrical themometers can be calibrated/scaled,to read a Suedo minus amount as can mechanical ones. whereas the Celcius scale Includes minus amounts.