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Lord Kelvin’s Water-drop Electrostatic Generator. Lord Kelvin’s Generator, On a Self-Acting Apparatus for Multiplying and Maintaining Electric Charges, with Applications to Illustrate the Voltaic Theory By Sir William Thomson (Lord Kelvin) Proceedings of the Royal Society , June 20, 1867.
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Lord Kelvin’s Water-drop Electrostatic Generator Lord Kelvin’s Generator, On a Self-Acting Apparatus for Multiplying and Maintaining Electric Charges, with Applications to Illustrate the Voltaic Theory By Sir William Thomson (Lord Kelvin) Proceedings of the Royal Society, June 20, 1867
What is Lord Kelvin’s Generator? • Water • Inducers • Collecting can
What is Lord Kelvin’s Generator? • Electrostatic charges are produced • The system seems to arbitrarily decide which side is positive and which is negative • Water drops can float or move against gravity
William Thompson (Baron Kelvin of Largs) • Born June 26th 1824 in Belfast, Ireland • Matriculated at the University of Glasgow at age 10 where his father was a professor • Graduated with a BA from Cambridge • Returned to fill the chair of natural philosophy (physics) at Glasgow Source: Institute of Physics, Belgrade http://octopus.phy.bg.ac.yu/web_projects/giants/kelvin.html
Work Towards Unifying Physics • Discussed with Joule the implications of heat being a form of motion (energy), and later endorsed Joule’s idea • Was mentor to James Clerk Maxwell, who acknowledged his debt to Thompson • Advanced the ideas of Michael Faraday
Other Accomplisments • Contributed to the design of the transatlantic cable • Was against AC current until the Chicago Exposition, after which he asked Westinghouse to use AC to harness the power of Niagara Fall • Ibid • Tesla – Master of Lightning – Harnessing Niagara • http://www.pbs.org/tesla/ll/ll_niagara.html
Back to the Generator • One application of the generator is to demonstrate the voltaic theory • Stored charges of different voltages can be used to produce a current
Possible Applications • Water ionizers can cost from $300 on up, I built my generator for less than $5 • Negatively charged water is said to reduce aging, be a powerful anti-oxidant, remove plaque from teeth, and substantially aid plant growth
Self Ionization of Water? • H2O(l) <=> H+(aq) + OH-(aq) • How much are we talking? • Kw = 10-14 M ions / 55.5 M @ 25oC
What’s an Ion Anyway? • Ion = Molecule with a proton/electron imbalance • Kw = 10-14 Moles Ions per 55.5 Mol H2O • In a neutral solution [H] = 10-7 M & [OH] = 10-7 M • pH = -log 10-7 = 7
So if I input a liter water… 1 liter H2O = 55.5 M So we have 10-14 M elementary charges 10-14 M * (6.02 * 1023 molecules/mole) = 6.02 * 109 molecules (6.02 * 109 molecules) * (1.60 * 10-19 C/molecule) = 9.63 * 10-10 C
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