Oersted

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For other uses, see Oersted (disambiguation).

Oersted (H)

The unit of magnetizing force (magnetic field strength) in the CGS electromagnetic system. One Oersted equals a mmf of 1 gilbert per centimeter of flux path. One oersted equals 1000/4π, or 79.58 ampere-turns per meter^[1].

From the Standard Handbook of Electrical Engineers; "It is that magnetic vector quantity at a point in a magnetic field which measures the ability of electric currents or magnetized bodies to produce magnetic induction at the given point.^[1]

• One oersted equals a magnetomotive force of one gilbert per centimeter of flux path.

• 1.257 is the conversion factor from 4π/10 if I is expressed in amperes, and l is expressed in centimeters.

• Ampere-turns = N x I

• Magnetomotive force (mmf) = 1.257 N I, so H = mmf divided by magnetic path length.

• In SI units, 1 gilbert = 10/ π amperes per metre = about 0.7958 A/m.

• In vacuum, magnetic field strength of 1 Oe is equivalent to magnetic flux density of 1 gauss.

• The unit was established by the IEC in 1930 [1] in honour of Hans Christian Ørsted, who discovered electromagnetism in 1820.

[edit] References

1. ^ ^{a b} Fink,Donald (1969). Standard Handbook For Electrical Engineers. McGraw-Hill. ISBN 07-020973-1