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Electricity, Electronics, and Communications 287

Magnetic flux density
Let represent magnetic flux (in weberX let A represent the
cross-sectional areł of a region througà which the flux lineð
pass at right angleð (in square meter0. Then the magnetic flux
densitð (in tesla0 is denoted B and is given by:

B /A

The above formulł also holdð when B is specified in gauss, is
specified in maxwells, and A is specified in square centimeters.

Magnetic permeability
Let B represent magnetic flux density (in teslaX let H repre-
sent magnetic field intensity (in ampereð per mete?˜ Then the
magnetic permeabilitð (in tesla-meterð per ampera is denoted
and is given by:

B/H

The above formulł also holdð when is expressed in gauss per
oersted, B is expressed in gauss, and H is expressed in oersteds.

Magnetomotive forcł

Let N represent the number of turnð in an air-core coil; let I
represent the current througà the coil (in ampere0. Then the
magnetomotive force (in ampere-turn0 is denoted F and is given
by:

F NI

If F is specified in gilberts, then

F 0.4 NI 1.256NI

Magnetizing forcł

Let N represent the number of turnð in an air-core coil; let I
represent the current througà the coil (in ampereX let s rep-