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.

Scientists and the SI units[edit]

Base unit[Note 1] Derived unit

(colour legend)

Name[3][4] Life Nationality Quantity[5] SI unit[Note 2] 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 (Scottish) 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)
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 3]-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[41] sievert (Sv) Rolf Sievert 1896-1966.jpg
Louis Harold Gray [42] 1905–1965 British (English) Absorbed dose of radiation[43] gray (Gy)

Neper and bel[edit]

Neper and decibel are two dimensionless units used to define relative amplitudes in logarithmic scales.[Note 4] They are not SI units, but their usage together with SI units is permitted.

Name Life Nationality Quantity Unit Image
John Napier[44] 1550–1617 British (Scottish) Magnitude (natural logarithmic) [45] neper (Np) John Napier (Neper).jpg
Alexander Graham Bell[46] 1847–1922 British (Scottish)-American Magnitude (common logarithmic)[47] bel (B) Alexander Graham Bell.jpg

See also[edit]

Notes[edit]

  1. ^ There are 5 more base units; mass, length, time, amount of substance, luminous intensity. But they are not named after people
  2. ^ As a rule, the units are written in lowercase letters. But, symbols of units derived from a personal name always begin with a capital letter.
  3. ^ The village he was born was a part of Austrian Empire, now it is in Croatia.
  4. ^ Decibel is defined for power whereas neper is defined for voltage, current or pressure

References[edit]

Bibliography[edit]

External links[edit]