Electric flux is a property of an electric field that may be thought of as the number of electric lines of force that intersect a given area.
The significance of the flux coming out of a closed surface is that it tells you the net charge inside that surface.
Formula to calculate total electric flux.
The permittivity of free space is a physical constant equal to approximately 8.85 x 10^12 farad per meter.
Example:
Suppose the enclosed charge in an area is 14 coulomb, calculate the electric flux.
Therefore, the electric flux is 1.58^-12 volt meters.