Kite experiment
The kite experiment is a scientific experiment in which a kite with a pointed conductive wire attached to its apex is flown near thunder clouds to collect static electricity from the air and conduct it down the wet kite string to the ground. The experiment was first proposed in 1752 by Benjamin Franklin, who reportedly conducted the experiment with the assistance of his son William. The experiment's purpose was to investigate the nature of lightning and electricity, which were not yet understood. Combined with further experiments on the ground, the kite experiment demonstrated that lightning and electricity were the result of the same phenomenon.
Background
Speculations of Jean-Antoine Nollet had led to the issue of the electrical nature of lightning being posed as a prize question at Bordeaux in 1749. In 1750, it was the subject of public discussion in France with a dissertation of Denis Barberet receiving a prize in Bordeaux. Barberet proposed a cause in line with the triboelectric effect. The same year, Franklin reversed his previous skepticism of electrical lightning's attraction to high points.[1] The physicist Jacques de Romas also wrote a mémoire with similar ideas that year and later defended them as independent of Franklin's.[2]
Lightning rod experiments
In 1752, Franklin proposed an experiment with
Franklin's kite experiment
Franklin's kite experiment was performed in Philadelphia in June 1752, according to the account by
According to the 1767 Priestley account, Franklin realized the dangers of using conductive rods and instead used the conductivity of a wet hemp string attached to a kite. As a result, he was able to remain on the ground and let his son fly the kite from the cover of a shed close by. That enabled Franklin and his son to keep the silk string of the kite dry to insulate them while the hemp string to the kite was allowed to get wet in the rain to provide conductivity. A house key was attached to the hemp string and connected to a Leyden jar; a silk string was attached to that. "At this key he charged phials, and from the electric fire thus obtained, he kindled spirits, and performed all other electrical experiments which are usually exhibited by an excited globe or tube." The kite was not hit by visible lightning; otherwise, Franklin would almost certainly have been killed.[10][11] However, Franklin noticed that loose threads of the kite string were repelling one another and deduced that the Leyden jar was being charged. He moved his hand near the key and observed an electric spark,[6] which proved the electric nature of lightning.[12]
References
- ISBN 978-2-88074-943-9. Retrieved September 1, 2018.
As for Franklin, who doubted in 1749 that the lightning was attracted by the spikes, he wrote ... the following year: 'When the electrified clouds pass over a country, the summits of mountains and trees, the high towers, the pyramids, the masts of the ships, the chimneys, etc., like so many eminences and peaks, attract the electric fire, and the whole cloud is unloaded.'
- ISBN 978-0-520-03478-5. Retrieved October 29, 2012.
- ISBN 978-0-226-72078-4. Retrieved October 29, 2012.
- ISBN 978-0-521-03541-5. Retrieved October 29, 2012.
- ^ "The History and People of Christ Church". Christ Church. Retrieved April 27, 2019.
- ^ a b c d National Archives, The Kite Experiment, 19 October 1752. Retrieved February 6, 2017
- ^ Franklin, Benjamin (October 19, 1752). "The Kite Experiment". The Pennsylvania Gazette. Archived from the original on September 22, 2010.
- ^ "Pennsylvania Gazette". Benjamin Franklin Historical Society. Retrieved February 6, 2017.
- ISBN 978-1-59448-401-8. Retrieved February 6, 2017
- ^ "Franklin Discovered Electricity with Kite". Mythbusters. April 11, 2012. Retrieved July 30, 2016.
- ^ "MythBusters S4-E9 Episode 48--"Franklin's Kite"". Mythbusters. March 8, 2006. Retrieved October 19, 2021.
- ^ "Benjamin Franklin and the Kite Experiment". The Franklin Institute. June 12, 2017. Retrieved April 13, 2021.
External links
- Philosophical Transactions: A Letter of Benjamin Franklin, Esq; to Mr. Peter Collinson, F. R. S. concerning an Electrical Kite. Phil. Trans. 1751–1752 47, 565–567; (PDF)
- http://www.pbs.org/benfranklin/shocking/