Search results
Results From The WOW.Com Content Network
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] It is represented by a pseudovector M.
The magnetization is the negative derivative of the free energy with respect to the applied field, and so the magnetization per unit volume is = , where n is the number density of magnetic moments. [1]: 117 The formula above is known as the Langevin paramagnetic equation.
Here μ 0 is the permeability of free space; M the magnetization (magnetic moment per unit volume), B = μ 0 H is the magnetic field, and C the material-specific Curie constant: = (+), where k B is the Boltzmann constant, N the number of magnetic atoms (or molecules) per unit volume, g the Landé g-factor, μ B the Bohr magneton, J the angular ...
Its SI unit is the radian per second per tesla (rad⋅s −1 ⋅T −1) or, equivalently, the coulomb per kilogram (C⋅kg −1). [citation needed] The term "gyromagnetic ratio" is often used [2] as a synonym for a different but closely related quantity, the g-factor. The g-factor only differs from the gyromagnetic ratio in being dimensionless.
The volume charge density ρ is the amount of charge per unit volume (cube), surface charge density σ is amount per unit surface area (circle) with outward unit normal n̂, d is the dipole moment between two point charges, the volume density of these is the polarization density P.
The gauss is the unit of magnetic flux density B in the system of Gaussian units and is equal to Mx/cm 2 or g/Bi/s 2, while the oersted is the unit of H-field. One tesla (T) corresponds to 10 4 gauss, and one ampere (A) per metre corresponds to 4π × 10 −3 oersted .
The magnetization of a magnetized material is the local value of its magnetic moment per unit volume, usually denoted M, with units A/m. [18] It is a vector field , rather than just a vector (like the magnetic moment), because different areas in a magnet can be magnetized with different directions and strengths (for example, because of domains ...
It is the ratio of magnetization M (magnetic moment per unit volume) to the applied magnetic field intensity H. This allows a simple classification, into two categories, of most materials' responses to an applied magnetic field: an alignment with the magnetic field, χ > 0 , called paramagnetism , or an alignment against the field, χ < 0 ...