Editing Magnetic flux (section)

== Magnetic flux through an open surface ==
[[File:Vector field on a surface.svg|right|thumb|250px|For an open surface Σ, the [[electromotive force]] along the surface boundary, ∂Σ, is a combination of the boundary's motion, with velocity '''v''', through a magnetic field '''B''' (illustrated by the generic '''F''' field in the diagram) and the induced electric field caused by the changing magnetic field.]]

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.

When determining the total magnetic flux through a surface only the boundary of the surface needs to be defined, the actual shape of the surface is irrelevant and the integral over any surface sharing the same boundary will be equal. This is a direct consequence of the closed surface flux being zero.