gar
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John120/240:
James Watt was dead before the electrical unit watt was created. I can not find with clarity when the unit was created. But maybe between 1879 and 1882.
My search includes at least the references below.
"Menlo Park Reminiscences", Volume One, by Francis Jehl. In this book I do not find a reference to the unit watt. In 1879 in the development of the dynamo "Long-Legged Mary Ann" tests were run measuring output current, voltage, temperature rise, and input mechanical power.
At this time the measurment of electrical power as V*I was known. For a long time mechanical power, in HP, could be related to torque and speed. See James Watt below for foor-pounds per minute. See Joule below for power equation. I did not see a reference of physically how Edison related mechanical power input to electrical output. Joule's work may have provided this information.
History of Steam Engines:
http://en.wikipedia.org/wiki/Steam_engine
James Watt:
http://en.wikipedia.org/wiki/James_Watt
James Watt and Horsepower:
http://en.wikipedia.org/wiki/Horsepower
1882 The unit watt was recognized:
http://en.wikipedia.org/wiki/Watt
James Prescott Joule:
http://en.wikipedia.org/wiki/Joule's_laws
No mention of the unit watt here.
Other references:
http://nvl.nist.gov/docspub/NIST_Hi...r_III.__ELECTRICITY__RAILROADS__AND_RADIO.pdf
http://www.unc.edu/~rowlett/units/dictW.html
http://library.thinkquest.org/C006011/english/sites/watt_bio.php3?v=2
http://en.wikipedia.org/wiki/International_System_of_Units
http://www.french-metrology.com/en/history/history-mesurement.asp
http://www.google.com/search?q=hist...ine_result&ct=title&resnum=11&ved=0CEMQ5wIwCg
.
John120/240:
No.Was it James Watt who figured out that 746 watts = 1 horse power?
James Watt was dead before the electrical unit watt was created. I can not find with clarity when the unit was created. But maybe between 1879 and 1882.
My search includes at least the references below.
"Menlo Park Reminiscences", Volume One, by Francis Jehl. In this book I do not find a reference to the unit watt. In 1879 in the development of the dynamo "Long-Legged Mary Ann" tests were run measuring output current, voltage, temperature rise, and input mechanical power.
At this time the measurment of electrical power as V*I was known. For a long time mechanical power, in HP, could be related to torque and speed. See James Watt below for foor-pounds per minute. See Joule below for power equation. I did not see a reference of physically how Edison related mechanical power input to electrical output. Joule's work may have provided this information.
History of Steam Engines:
http://en.wikipedia.org/wiki/Steam_engine
James Watt:
http://en.wikipedia.org/wiki/James_Watt
James Watt and Horsepower:
http://en.wikipedia.org/wiki/Horsepower
1882 The unit watt was recognized:
http://en.wikipedia.org/wiki/Watt
Origin and adoption as an SI unit
The watt is named after James Watt for his contributions to the development of the steam engine. The unit was recognized by the Second Congress of the British Association for the Advancement of Science in 1882. The 11th General Conference on Weights and Measures in 1960 adopted it for the measurement of power into the International System of Units (SI).
James Prescott Joule:
http://en.wikipedia.org/wiki/Joule's_laws
No mention of the unit watt here.
Other references:
http://nvl.nist.gov/docspub/NIST_Hi...r_III.__ELECTRICITY__RAILROADS__AND_RADIO.pdf
http://www.unc.edu/~rowlett/units/dictW.html
http://library.thinkquest.org/C006011/english/sites/watt_bio.php3?v=2
http://en.wikipedia.org/wiki/International_System_of_Units
http://www.french-metrology.com/en/history/history-mesurement.asp
http://www.google.com/search?q=hist...ine_result&ct=title&resnum=11&ved=0CEMQ5wIwCg
.