List of scientists whose names are used as SI units

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List of scientists whose names are used as SI units is the list of those scientists whose names are assigned as the names of the international units by the International Committee for Weights and Measures. The International System of Units (abbreviated SI from French: Système international d'unités) is the most widely used system of units of measurement. There are seven base units and 22 derived units[1] (excluding compound units). These units are used both in science and in commerce. Two of the base units and 17 of the derived units are named after scientists.[2] By this convention, their names are immortalised. Below is the list of the scientists whose names are used as SI units. As a rule, the units are written in lowercase letters, but symbols of units derived from the name of a person begin with a capital letter.

Scientists and the SI units

Base unit[note 1] Derived unit

(colour legend)

Name[3][4] Life Nationality Quantity[5] SI unit Image
André-Marie Ampère[6] 1775–1836 French Electric current[7] ampere (A)
(Base unit)
Ampere Andre 1825.jpg
William Thomson, 1st Baron Kelvin[8] 1824–1907 British (Irish) Thermodynamic temperature[9] kelvin (K)
(Base unit)
Lord Kelvin photograph.jpg
Blaise Pascal[10] 1623–1662 French Pressure[11] pascal (Pa) Blaise pascal.jpg
Isaac Newton[12] 1643–1727 British (English) Force[13] newton (N) GodfreyKneller-IsaacNewton-1689.jpg
Anders Celsius[14] 1701–1744 Swedish Temperature[15] degree Celsius (°C)
Headshot of Anders Celsius.jpg
Charles-Augustin de Coulomb[16] 1736–1806 French Electric charge[17] coulomb (C) Charles de coulomb.jpg
James Watt[18] 1736–1819 British (Scottish) Power[19] watt (W) Watt James von Breda.jpg
Alessandro Volta[20] 1745–1827 Italian Electric potential[21] volt (V) Volta A.jpg
Georg Simon Ohm[22] 1789–1855 German Electrical resistance[23] ohm (Ω) Ohm3.gif
Michael Faraday[24] 1791–1867 British (English) Capacitance[25] farad (F) Michael Faraday 001.jpg
Joseph Henry[26] 1797–1878 American Inductance[27] henry (H) Joseph Henry (1879).jpg
Wilhelm Eduard Weber[28] 1804–1891 German Magnetic flux[29] weber (Wb) Wilhelm Eduard Weber II.jpg
Ernst Werner von Siemens[30] 1816–1892 German Conductance[31] siemens (S) Ernst Werner von Siemens.jpg
James Prescott Joule[32] 1818–1889 British (English) Energy[33] joule (J) Joule James Jeens engraving.jpg
Antoine Henri Becquerel[34] 1852–1908 French Radioactivity[35] becquerel (Bq) Becquerel Henri photograph.jpg
Nikola Tesla[36] 1856–1943 Serbian[note 2]-American Magnetic flux density[37] tesla (T) Tesla3.jpg
Heinrich Rudolf Hertz[38] 1857–1894 German Frequency[39] hertz (Hz) Heinrich Rudolf Hertz.jpg
Rolf Maximilian Sievert[40] 1896–1966 Swedish Dose equivalent of radiation[citation needed] sievert (Sv) Rolf Sievert 1896-1966.jpg
Louis Harold Gray[41] 1905–1965 British (English) Absorbed dose of radiation[42] gray (Gy)

Napier and Bell

Napier and decibel are two dimensionless units used to define relative amplitudes in logarithmic scales.[note 3] They are not SI units, but their usage together with SI units is permitted.

Name Life Nationality Quantity Unit Image
John Napier[43] 1550–1617 British (Scottish) Magnitude (natural logarithmic)[44] neper (Np) John Napier (Neper).jpg
Alexander Graham Bell[45] 1847–1922 British (Scottish)-American Magnitude (common logarithmic)[46] bel (B) Alexander Graham Bell.jpg

See also


  1. ^ There are 5 base units that are not named after people: kilogram, metre, second, mole and candela.
  2. ^ The village he was born was a part of Austrian Empire, now it is in Croatia.
  3. ^ Decibel is defined for power whereas neper is defined for voltage, current or pressure


  1. ^ Essential of the SI
  2. ^ Derived SI units with special names
  3. ^ Asimov's Biographical Encyclopedia
  4. ^ Elektrik Mühendisliği pp. 247–275
  5. ^ Young and Freedman, p. A-1
  6. ^ Marie Ampere
  7. ^ Ampere on Dictionary
  8. ^ Kelvin, Lord William Thomson
  9. ^ Inventors
  10. ^ Blaise Pascal
  11. ^ Pa Pascal pressure unit
  12. ^ Isaac Newton's life
  13. ^ Newton
  14. ^ Anders Celsius (1701–1744)
  15. ^ Celsius Definition
  16. ^ Charles Augustin de Coulomb (French Physicist)
  17. ^ Coulomb
  18. ^ BBC Historic figures
  19. ^ Watt conversion)
  20. ^ Inventor Alessandro Volta Biography
  21. ^ Volt
  22. ^ georg Simon Ohm
  23. ^ Ohm (unit)
  24. ^ Michael Faraday
  25. ^ Farad
  26. ^ Joseph Henry Archived 9 December 2006 at the Wayback Machine.
  27. ^ Henry: Definition from Answers
  28. ^ The New International Encyclopaedia: Weber
  29. ^ Weber (unit)
  30. ^ Siemens, Werner von
  31. ^ Siemens (unit)
  32. ^ Biography:James Prescott Joule
  33. ^ What is a Joule ?
  34. ^ Henri Becquerel
  35. ^ Becquerel
  36. ^ Tesla's Biography
  37. ^ Tesla (unit)
  38. ^ Heinrich Hertz
  39. ^ Hertz
  40. ^ Rolf Sievert, the man and the unit
  41. ^ About L.G.Gray
  42. ^ Gray
  43. ^ Biography:Napier
  44. ^ Neper explained
  45. ^ Graham Bell
  46. ^ Decibel


  • "Essentials of the SI". Retrieved 3 May 2011.
  • Gordon England. "Derived SI units with special names". Retrieved 3 May 2011.
  • Asimov, Isaac (1972). Asimov's Biographical Encyclopedia of Science and Technology. London: Pan Books. ISBN 0-330-24323-3.
  • İnan, Kemal (1978). Elektrik Mühendisliği (259-260) : Elektrik. Ankara: TBMMO EMO Yayın organı.
  • Hugh Young, Roger Freedman. University Physics. Addison Wesley. ISBN 0-321-50130-6.
  • Eric W. Weisstein. "Kelvin, Lord William Thomson (1824-1907)". Wolfram Research. Retrieved 3 May 2011.
  • Alfred Ruppert Hall. "Isaac Newton's Life". Isaac Newton Institute for Mathematical Sciences. Retrieved 3 May 2011.
  • "Anders Celsius (1701-1744)". Uppsala University. Retrieved 3 May 2011.
  • "Charles Augustin de Coulomb (French physicists)". Encyclopædia Britannica. Retrieved 5 May 2011.
  • "Coulomb". Encyclopædia Britannica. Retrieved 3 May 2011.
  • Julian Trubin. "Georg Simon Ohm". Retrieved 3 May 2011.
  • "Ohm (unit)". The Free Dictionary by Farlex. Retrieved 3 May 2011.
  • "Michael Faraday". Famous Physicists and Astronomers. Retrieved 3 May 2011.
  • "Joseph Henry". The national academy of sciences. Archived from the original on 9 December 2006. Retrieved 3 May 2011.
  • "Weber, Wilhelm". The New International Encyclopaedia. Retrieved 3 May 2011.
  • "Siemens, Werner von". Encyclopædia Britannica. Retrieved 3 May 2011.
  • "Siemens (unit)". Medlib. Retrieved 3 May 2011.
  • "Biography:James Presacott Joule". Oracle ThinkQuest. Retrieved 3 May 2011.
  • "Henri Becquerel". Retrieved 3 May 2011.
  • "Becquerel". Retrieved 3 May 2011.
  • Dr.Ljubo Vujović. "Tesla's Biography". Tesla Memorial Society of New York. Retrieved 3 May 2011.
  • "Tesla Unit". Tesla Memorial Society of New York. Retrieved 3 May 2011.
  • "Heinrich Hertz". Biograhpicon. Retrieved 3 May 2011.
  • "Hertz". University of California, Berkeley. Retrieved 4 May 2011.
  • Mariann Eklund. "Rolf Sievert, the man and the unit". Karolinska Institutet. Retrieved 3 May 2011.
  • "About L.G.Gray". L.G.Gray Memorial Trust. Retrieved 3 May 2011.
  • "Decibel". NDT resource center. Retrieved 3 May 2011.

External links

  • Physical dimensions of the units
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