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not the way the coulomb is defined Undid revision 410829737 by Sbyrnes321 (talk)
could we get a reference for this part?
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See also [[SI prefix#List of SI prefixes|SI prefix]].
See also [[SI prefix#List of SI prefixes|SI prefix]].

== In everyday terms ==
{{unreferenced section}}
*The charges in [[static electricity]] from rubbing materials together are typically a few microcoulombs.<ref>[http://cherenkov.physics.iastate.edu/~mkpohl/teach/112/ch16.pdf]</ref>
*The amount of charge that travels through a [[lightning bolt]] is typically around 15C, although large bolts can be up to 350C.<ref>Hasbrouck, Richard. [https://www.llnl.gov/str/pdfs/05_96.1.pdf Mitigating Lightning Hazards], Science & Technology Review May 1996. Retrieved on 2009-04-26.</ref>
*The amount of charge that travels through a typical [[Alkaline battery|alkaline]] [[AA battery]] is about 10 kC = 10<sup>4</sup> C = 2800 [[mAh]]. After that charge has flowed, the battery must be discarded or recharged.
*According to [[Coulomb's Law]], two [[point charge]]s of +1 C, one meter apart, would experience a repulsive [[force]] of 9{{e|9}} N, a force roughly equal to the weight of 900,000 metric tons of [[mass]].


== Conversions ==
== Conversions ==

Revision as of 22:20, 29 January 2011

For other uses, see Coulomb (disambiguation).
coulomb
Unit systemSI derived unit
Unit ofElectric charge
SymbolC
Named afterCharles-Augustin de Coulomb
Conversions
1 C in ...... is equal to ...
   SI base units   1 A s
   CGS units   2997924580 statC
   Atomic units   6.242×1018 e

The coulomb (symbol: C) is the SI derived unit of electric charge, transported by a steady current of one ampere in one second.

One coulomb is also the amount of excess charge on the positive side of a capacitance of one farad charged to a potential difference of one volt:

Name

The unit is named after Charles-Augustin de Coulomb.[1] The coulomb is named after Charles-Augustin de Coulomb. As with every SI unit named for a person, its symbol starts with an upper case letter (C), but when written in full, it follows the rules for capitalisation of a common noun; i.e., coulomb becomes capitalised at the beginning of a sentence and in titles but is otherwise in lower case.

Explanation

The magnitude of an elementary charge, the charge of a proton or electron, is approximately 1.602176487(40)×10−19 coulombs.[2] In principle, the coulomb could be defined in terms of the elementary charge. Since the values of the Josephson [3] constants have been given conventional values (KJ ≡ 4.835 979×1014 Hz/V and RK ≡ 2.581 280 7×104 Ω), it is possible to combine these values to form an alternative (not yet official) definition of the coulomb. A coulomb is then equal to exactly 6.241 509 629 152 65×1018 positive elementary charges. Combined with the present definition of the ampere, this proposed definition would make the kilogram a derived unit.

In everyday situations, positive and negative charges are usually balanced out. According to Coulomb's Law, two point charges of +1 C, one meter apart, would experience a repulsive force of 9×109 N, a force roughly equal to the weight of 900,000 metric tons of mass.

SI prefixes

SI multiples of coulomb (C)
Submultiples Multiples
Value SI symbol Name Value SI symbol Name
10−1 C dC decicoulomb 101 C daC decacoulomb
10−2 C cC centicoulomb 102 C hC hectocoulomb
10−3 C mC millicoulomb 103 C kC kilocoulomb
10−6 C μC microcoulomb 106 C MC megacoulomb
10−9 C nC nanocoulomb 109 C GC gigacoulomb
10−12 C pC picocoulomb 1012 C TC teracoulomb
10−15 C fC femtocoulomb 1015 C PC petacoulomb
10−18 C aC attocoulomb 1018 C EC exacoulomb
10−21 C zC not used 1021 C ZC zettacoulomb
10−24 C yC not used 1024 C YC yottacoulomb
10−27 C rC rontocoulomb 1027 C RC ronnacoulomb
10−30 C qC quectocoulomb 1030 C QC quettacoulomb
Common multiples are in bold face.

See also SI prefix.

In everyday terms

  • The charges in static electricity from rubbing materials together are typically a few microcoulombs.[4]
  • The amount of charge that travels through a lightning bolt is typically around 15C, although large bolts can be up to 350C.[5]
  • The amount of charge that travels through a typical alkaline AA battery is about 10 kC = 104 C = 2800 mAh. After that charge has flowed, the battery must be discarded or recharged.
  • According to Coulomb's Law, two point charges of +1 C, one meter apart, would experience a repulsive force of 9×109 N, a force roughly equal to the weight of 900,000 metric tons of mass.

Conversions

  • The magnitude of the electrical charge of one mole of protons (approximately 6.022×1023, or Avogadro's number) is known as the Faraday constant or a faraday. One faraday is equal to 96485.3399 coulombs. In terms of Avogadro's number (NA), one coulomb is equal to approximately 1.036 × NA ×10−5 elementary charges.
  • one ampere-hour = 3600 C, one mAh = 3.6 C
  • The elementary charge is 1.602176487×10−19 C
  • One statcoulomb (statC), the CGS electrostatic unit of charge (esu), is approximately 3.3356×10−10 C or about 1/3 nC.
  • One coulomb is the amount of electrical charge in 6.241506×1018 protons, or equivalently, negative one (-1) coulomb is the electrical charge of 6.241506×1018 electrons.

See also

References

  1. ^ BIPM SI Brochure, Appendix 1, p. 144
  2. ^ Template:CODATA2006
  3. ^ CIPM (1988) Recommendation 1, PV 56; 19) and von Klitzing (CIPM (1988), Recommendation 2, PV 56; 20
  4. ^ [1]
  5. ^ Hasbrouck, Richard. Mitigating Lightning Hazards, Science & Technology Review May 1996. Retrieved on 2009-04-26.
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