Is magnetic flux possible through an open surface?

AI Thread Summary
Magnetic flux can indeed occur through an open surface, particularly when a magnetic field changes over time, which can induce electromotive force (emf) in a circular arc. Magnetic fields propagate through space and can be influenced by materials, with ferromagnetic substances guiding them more effectively. The term "flux" can refer to total flow through a surface or flow per unit area, but in electromagnetism, it specifically denotes total flow as a scalar quantity. According to Gauss' law, the scalar flux of an electric field through a closed surface is related to the enclosed charge, while the magnetic flux through a closed surface is zero. Understanding these principles is crucial for applications in electromagnetism and related fields.
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Is it possible to have magnetic flux through an open surface ?
i mean if there is a circular arc and magnetic field at the centre changes with time then will there be any induced emf in the arc ?
 
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Yes it is possible.

Magnetic fields travel through space.
They like to travel through some materials better than others(Ferric), so you can guide them with the right material.

Definition/Summary
Flux sometimes means total flow through a surface (a scalar), and sometimes means flow per unit area (a vector).

In electromagnetism, flux always means total flow through a surface (a scalar).

Scalar flux is the amount of a vector field going through a surface: it is the integral (over the surface) of the normal component of the field:

For a closed surface, this equals (Gauss' theorem, or the divergence theorem) the integral (over the interior) of the divergence of the field: .

Therefore the scalar flux, through a closed surface, of an electric field is proportional to the enclosed charge (Gauss' law: ), and of a magnetic field is zero (Gauss' law for magnetism: ).
 
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