მაგნიტური ნაკადი: განსხვავება გადახედვებს შორის

for any [[closed surface]] ''S''.

 

While the magnetic flux through a [[closed surface]] is always zero, the magnetic flux through an [[open surface]] is an important quantity in electromagnetism. 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. The relationship is given by [[Faraday's law of induction|Faraday's law]]:

 

:<math>\mathcal{E} = \oint_{\partial \Sigma (t)}\left( \mathbf{E}( \mathbf{r},\ t) +\mathbf{ v \times B}(\mathbf{r},\ t)\right) \cdot d\boldsymbol{\ell} = -{d\Phi_m \over dt},</math>

 

:''<font style="font-family: Brush Script MT; font-size:130%;">E</font>'' is the [[electromotive force|EMF]],

:<font style="font-family: Times New Roman; font-size:110%;">Φ</font>_m is the flux through a surface with an opening bounded by a curve '''''∂Σ'''''(''t''),