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Knowledge of magnetism

1.Magnetic Field: the space that can produce magnetic force to magnetic pole.

2.Magnetic Field Intensity: (H) magnetic field electrical which was produced by electrical gyroidal winding.Namely,if the unitage length of electrical gyroidal winding is “n” and the passing electric current is “I(A)” then H=I*n.

3.Flux Density (B): the product of vacuum magnetoconductivity (μ)and intensity of magnetic B=μ*H

4.Flux: flux density of unitage area ∮=B*S(“S” is unitage area)

5.Max Energy Product (BH(max)): smallest volume exists most large magnetic power.

6.Coercive Force (Hcb): magnetic field intensity which realize to change the magnetic direction opposite to earlier direction.Namely, if the process is controlled by remove magnetic domain then the power that resist this process called Coercive Force.

7.Residual .Flux Density(Br): magnetic induction intensity(Flux Density) when saturated magnet (including magnetic field which demagnetized by itself)decrease monotonously according to saturated hysteresis curves to zero.

8.Sreface Magnetic Field: appointed palce on permanent magnet.

9.Anisotropic magnet:different crystal has easy or difficult magnetic direction characteristic it attribute to the direction of crystal component.

Mainly magnetics unitage and physical unitage chart

Physical name and notationSI unitConversion formualCGS Gauss systemIA1A=3*10esu VmA1A= GillbertGillbertRm1A/wb=1emuH1A/M=OeBT1T=GSCM∮Mx

*esu is static unitage units *emu is electromagnetic unitage units