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P: 38
i have read the articles where the flux (either in case of electric flux or magnetic )is described as the no of lines passing through a surface area ( open in case of magnetic characterized by boundary and closed in case of electric flux density) or considered as an component of electric field or mag. field through that surface..
below is exact context:-
 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). Note that 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 component of the magnetic field passing through a surface
from:- http://en.wikipedia.org/wiki/Magnetic_flux
but rather my textbook defines that it is convenient to replace sometimes the magnetic or electric field lines with flux lines..!!
FLUX LINES...: if its a scalar then how could we associate lines with it i mean we are here concerned with no of lines which is absolutely a scalar..
and further there was a post here about differences bet flux and flux density
and it was made clear that:-
 Magnetic flux, Φ, is a scalar, measured in webers (or volt-seconds), and is a total amount measured across a surface (ie, you don't have flux at a point). Magnetic flux density, B, is a vector, measured in webers per square metre (or teslas), and exists at each point. The flux across a surface S is the integral of the magnetic flux density over that surface: Φ = ∫∫S B.dS (and is zero for a closed surface) Magnetic flux density is what physicists more commonly call the magnetic field. It is a density per area, rather than the usual density per volume.