Relationship Between B And H Field

The quantity m in these relationships is called the magnetization of the material.

Relationship between b and h field. More amps more turns shorter core means more field lines bigger h aturns m higher permeability measure of how easily those field lines can flow means they can be packed tighter together in the core larger b more intense magnetic field. Where χ is called the volume magnetic susceptibility and. Symbol name units e electric field v m n c p polarization c m2 d electric displacement c m2 b magnetic induction n a m. The quantity h plays the role of d for the table i.

Begingroup h is a bit like the number of magnetic field lines and b kinda is how tightly packed they are. The names and units of the six electromagnetic flelds. E d p b h and m. The fields h and b as in the electric case we have two flelds in the mag netic case.

The magnetization defines the auxiliary magnetic field h as gaussian units which is convenient for various calculations. A static b field actually d dt b n da 0 cannot produce an electric field e. Thus b is related to the properties of the material and its relation to the applied excitation e g. In diamagnets and paramagnets the relation is usually linear.

The vacuum permeability μ 0 is by definition 4π 10 7 v s a m. B μ m h. Even if we used natural units where μ. Electric current can be highly non linear.

If the medium is non continuous or anisotropic then magnetic poles or a demagnetising field could be created which themselves become sources of local excitation and they add to the source. Bio savart law gives us b which i suppose is magnetic field. If the magnetisation current i is increased in a positive direction to some value the magnetic field strength h increases linearly with i and the flux. Starting with an unmagnetised core both b and h will be at zero point 0 on the magnetisation curve.

Historically the term magnetic field was reserved for h while. Based on maxwell s equations electric fields are generated by changing b fields while h fields are generated by changing electric fields. B μ 0 h m h and m will have the same units amperes meter. In dc fields static electric e fields create currents magnetization currents i when σ 0 which in turn produce static h fields.

The magnetic hysteresis loop above shows the behaviour of a ferromagnetic core graphically as the relationship between b and h is non linear. Another commonly used form for the relationship between b and h is. While both the best names for these fields and exact interpretation of what these fields represent has been the subject of long running debate there is wide agreement about how the underlying physics work. There are two different but closely related fields which are both sometimes called the magnetic field written b and h.