The total flux is then a formal summation of these surface elements (see, Each point on a surface is associated with a direction, called the, Learn how and when to remove this template message, Mathematical descriptions of the electromagnetic field, Conversion Magnetic flux Φ in nWb per meter track width to flux level in dB – Tape Operating Levels and Tape Alignment Levels, https://en.wikipedia.org/w/index.php?title=Magnetic_flux&oldid=984825175, Articles lacking in-text citations from July 2016, Creative Commons Attribution-ShareAlike License, This page was last edited on 22 October 2020, at 09:51. The magnetic interaction is described in terms of a vector field, where each point in space is associated with a vector that determines what force a moving charge would experience at that point (see Lorentz force). where B is the magnitude of the magnetic field (the magnetic flux density) having the unit of Wb/m2 (tesla), S is the area of the surface, and θ is the angle between the magnetic field lines and the normal (perpendicular) to S. For a varying magnetic field, we first consider the magnetic flux through an infinitesimal area element dS, where we may consider the field to be constant: A generic surface, S, can then be broken into infinitesimal elements and the total magnetic flux through the surface is then the surface integral. Magnetic Flux Density Unit. The magnetic flux is the net number of field lines passing through that surface; that is, the number passing through in one direction minus the number passing through in the other direction (see below for deciding in which direction the field lines carry a positive sign and in which they carry a negative sign). In more advanced physics, the field line analogy is dropped and the magnetic flux is properly defined as the surface integral of the normal component of the magnetic field passing through a surface. The weber is named after the German physicist Wilhelm Eduard Weber (1804–1891). The magnetic flux through some surface, in this simplified picture, is proportional to the number of field lines passing through that surface (in some contexts, the flux may be defined to be precisely the number of field lines passing through that surface; although technically misleading, this distinction is not important). Its symbol is B, and its SI unit is the Tesla (T). In physics, specifically electromagnetism, the magnetic flux (often denoted Φ or ΦB) through a surface is the surface integral of the normal component of the magnetic field flux density B passing through that surface. The following formula expresses the flux density:Where Φ is the flux and A is the cross-sectional area in square meters (m2) of the magnetic field. By way of contrast, Gauss's law for electric fields, another of Maxwell's equations, is. [2] One tesla equals one weber per square meter (WB/m2). In other words, Gauss's law for magnetism is the statement: While the magnetic flux through a closed surface is always zero, the magnetic flux through an open surface need not be zero and is an important quantity in electromagnetism. [1] Since a vector field is quite difficult to visualize at first, in elementary physics one may instead visualize this field with field lines. In physics, specifically electromagnetism, the magnetic flux (often denoted Φ or ΦB) through a surface is the surface integral of the normal component of the magnetic field flux density B passing through that surface. This is a direct consequence of the closed surface flux being zero. The SI unit of magnetic flux is the weber (Wb; in derived units, volt–seconds), and the CGS unit is the maxwell. In physics, the weber ( / ˈveɪb -, ˈwɛb.ər / VAY-, WEH-bər; symbol: Wb) is the SI derived unit of magnetic flux. A flux density of one Wb/m 2 (one weber per square metre) is one tesla . This equation is the principle behind an electrical generator. Gauss's law for magnetism, which is one of the four Maxwell's equations, states that the total magnetic flux through a closed surface is equal to zero.

The flux of E through a closed surface is not always zero; this indicates the presence of "electric monopoles", that is, free positive or negative charges. If the magnetic field is constant, the magnetic flux passing through a surface of vector area S is. The SI Unit for flux density is the Tesla (T) which is defined as; $B=\frac{\varphi }{A}$ $B=\frac{Wb}{{{m}^{2}}}=Tesla$ “If one line of magnetic field passes normally through m 2 area, the magnetic flux density, B, will be one Tesla, Example of Magnetic Flux Density The magnetic flux density is the amount of flux per unit area perpendicular to the magnetic field. For example, a change in the magnetic flux passing through a loop of conductive wire will cause an electromotive force, and therefore an electric current, in the loop. Magnetic flux is usually measured with a fluxmeter, which contains measuring coils and electronics, that evaluates the change of voltagein the measuring coils to calculate the measurement of …