Home » BASIC FUNDA » ELECTRIC FLUX… GAUSS’S LAW

ELECTRIC FLUX: This is the total number of electric force lines passing through a surface.

• The lines of force passed the surface is unit area.
• Lines of forces acted perpendicularly on the surface.
• The S.I unit of electric flux is Volt-Meter.
ELECTRIC FLUX DENSITY: Electric flux density represents the electric flux per unit area.
The S.I unit of flux density is C/m2.
Suppose Q coulomb passes an area of d m2, then the flux density is
D = Q/d C/m2. d=4πr2 let radius = r.
So, D = Q/4πr2 C/m2.

RELATION BETWEEN ELECTRIC FIELD INTENSITY AND FLUX DENSITY: Field intensity is the strength of a point inside the electric field, whereas flux density is the unit area’s electric flux.
We know that, E = Q/4πЄr2 = Q/4πЄ0Єrr2 N/C.
From previous discussion, we also know that, D = Q/4πr2 .
Hence the relation is E = D/Є0Єr N/C or we can say the electric field intensity is the ratio of electric flux density and the permeability of the medium.

GAUSS’S FLUX THEOREM: Gauss’s law dictates about the behavior of electric field around electric charges. This law states that the net electric flux out of a closed surface is equal to the enclosed electric charge divided by the permittivity of free space.
As per Gauss’s law, Total electric flux, ø = enclosed charge,Q/Є0.
This law formulated in the 19th century and it is one of the four Maxwell’s equation about the force of electromagnetism.