Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] History of MASS



Serendipitously, I found this rather late distinction between mass and weight (last sentence):

Avogadro developed this hypothesis after Joseph Louis Gay-Lussac <http://en.wikipedia.org/wiki/Joseph_Louis_Gay-Lussac> had published in 1808 his law <http://en.wikipedia.org/wiki/Law_of_Charles_and_Gay-Lussac> on volumes (and combining gases). The greatest difficulty Avogadro had to resolve was the huge confusion at that time regarding atoms and molecules - one of the most important contributions of Avogadro's work was clearly distinguishing one from the other, admitting that simple particles too could be composed of molecules, and that these are composed of atoms. For instance, John Dalton <http://en.wikipedia.org/wiki/John_Dalton> did not consider this possibility. Avogadro did not actually use the word "atom" as the words "atom" and "molecule" were used almost without difference. He considered that there were three kinds of "molecules," including an "elementary molecule" (our "atom"). Also, a keener attention was given to the definition of mass <http://en.wikipedia.org/wiki/Mass>, as distinguished from weight <http://en.wikipedia.org/wiki/Weight>.

http://en.wikipedia.org/wiki/Amedeo_Avogadro



David Abineri wrote:

Thanks again for all the reactions. I guess my follow-up question would: was the concept of mass used prior to Galileo and if so what was the catalyst that pointed to the concept as being needed?

Thanks again, David Abineri