weber (unit)

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In physics, the weber (symbol: Wb; /ˈvbər/, /ˈwɛbər/, or /ˈwbər/) is the SI unit of magnetic flux. A flux density of one Wb/m2 (one weber per square meter) is one tesla.

The weber is named for the German physicist Wilhelm Eduard Weber (1804–1891).

Definition[change | edit source]

The weber may be defined in terms of Faraday's law, which relates a changing magnetic flux through a loop to the electric field around the loop. A change in flux of one weber per second will induce an electromotive force of one volt (produce an electric potential difference of one volt across two open-circuited terminals).

Officially,

Weber (unit of magnetic flux) — The weber is the magnetic flux which, linking a circuit of one turn, would produce in it an electromotive force of 1 volt if it were reduced to zero at a uniform rate in 1 second.[1]

In SI base units, the dimensions of the weber are (kg·m2)/(s2·A). Many times, the weber is expressed in terms of other derived units as the Tesla-square meter (T·m2), volt-seconds (V·s), or joules per ampere (J/A).

1 Wb = 1 V·s = 1 T·m2 = 1 J/A = 108 Mx (maxwells).

References[change | edit source]

  1. "CIPM, 1946: Resolution 2 / Definitions of Electrical Units". International Committee for Weights and Measures (CIPM) Resolutions. International Bureau of Weights and Measures (BIPM). 1946. http://www.bipm.org/en/CIPM/db/1946/2/. Retrieved 2008-04-29.