Magnetic Flux Density

Magnetic Flux Density The Magnetic Flux Density (B) is related to the Magnetic Field (H) by: [Equation 1] In Equation [1], is the permeability of the medium (material) where we are measuring the fields. The magnetic flux density is measured in Webers per square meter [Wb/m^2], which is equivalent to Teslas [T]. The B field is a vector field, which means it has a magnitude and direction at each point in space. We know that a particle with a charge q [C] will experience a force when in the presence of an Electric Field E. In addition, it is also known that if the charged particle is moving at velocity v perpendicular to a B field, then it will also experience a force proportional to the B field. This force can be written as: [Equation 2] In Equation [2], x is the cross product. This means that if the charge is travelling parallel to the B field, there will be no force exerted due to the B field. If the charge is travelling perpendicular to the B field, then a force of magnitude q*|v|*|B| is applied in a direction perpendicular to both v and B. As an example, if the particle is travelling in the +x-direction, and a magnetic flux density B is directed in the +y-direction, then the force will push the particle in the +z-direction if q is positive, and in the -z-direction if q is negative. The Lorentz Force Equation ties the force due to an external electric field E and an external magnetic flux density B on a charged particle moving at velocity v: [Equation 3] In summary, the Magnetic Flux Density is somewhat analogous to the Electric Field in that it can exert a force on a charged particle, although in a different way. In general, the magnetic field H and the Magnetic Flux Density B can be used somehwat interchangably, and are related by the permeability in Equation [1]. Maxwell's Equations This page on the magnetic flux density (B-field) is copyrighted. No portion can be reproduced except with permission. The copyright belongs to Maxwells-Equations.com, 2012.