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In classical electromagnetism, magnetization is the vector field that expresses the density of permanent or induced magnetic dipole moments in a magnetic material. Accordingly, physicists and engineers usually define magnetization as the quantity of magnetic moment per unit volume. [ 1 ]
Magnetic reluctance, or magnetic resistance, is a concept used in the analysis of magnetic circuits. It is defined as the ratio of magnetomotive force (mmf) to magnetic flux . It represents the opposition to magnetic flux, and depends on the geometry and composition of an object.
When a magnetic field along the axis is turned on (B points directly out of the screen), the Lorentz force drives a circular component of current, and the resistance between the inner and outer rims goes up. This increase in resistance due to the magnetic field is called magnetoresistance.
The field due to magnetic charges is obtained through Coulomb's law with magnetic instead of electric charges. If the magnetic pole distribution is known, then the magnetic pole model gives the exact distribution of the magnetic field intensity H both inside and outside the magnet. The surface charge distribution is uniform, if the magnet is ...
Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off. (Though, magnetization continues to increase very slowly with the field due to paramagnetism.)
Paramagnetism, ferromagnetism, and spin waves. Ferromagnetism is a property of certain materials (such as iron) that results in a significant, observable magnetic permeability, and in many cases, a significant magnetic coercivity, allowing the material to form a permanent magnet.
Magnetic moment, magnetic dipole moment: m, μ B, Π: Two definitions are possible: using pole strengths, = using currents: = ^ a = pole separation N is the number of turns of conductor A m 2 [I][L] 2: Magnetization: M
Assuming the external magnetic field is uniform and shares a common axis with the paramagnet, the extensive parameter characterizing the magnetic state is , the magnetic dipole moment of the system. The fundamental thermodynamic relation describing the system will then be of the form U = U ( S , V , I , N ) {\displaystyle U=U(S,V,I,N)} .