Lord Kelvin

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Lord Kelvins Water-drop Electrostatic Generator

• Lord Kelvins 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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What is Lord Kelvins Generator?

• Water
• Inducers
• Collecting can

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How it Works
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What is Lord Kelvins 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

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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//octo
pus.phy.bg.ac.yu/web_projects/giants/kelvin.html
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Work Towards Unifying Physics

• Discussed with Joule the implications of heat
  being a form of motion (energy), and later
  endorsed Joules idea
• Was mentor to James Clerk Maxwell, who
  acknowledged his debt to Thompson
• Advanced the ideas of Michael Faraday

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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

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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

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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

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Self Ionization of Water?

• H2O(l) ltgt H(aq) OH-(aq)
• How much are we talking?
• Kw 10-14 M ions / 55.5 M _at_ 25oC

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Whats 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

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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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Triboelectric Series

• asbestos
• glass
• human hair
• nylon
• wool
• lead
• silk
• aluminum
• paper
• cotton
• steel
• hard rubber
• nickel copper
• brass silver
• synthetic rubber
• orlon
• saran wrap
• polyethylene
• teflon

• Some triboelectic series contradict others

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