Chapter-1|Electric Charges and Fields | NCERT 12th Physics:
Electric flux linked with any surface is defined as the total number of electric field lines that normally passes through that surface. It is represented by ØE.
Electric flux depends upon three factors.
(II) Strength of electric field.
(III) Angle between area vector and electric field.
Since, we will consider only perpendicular electric field lines through surface, so we will take only cos component.
Therefore, If θ is the angle between area vector and electric field, then electric flux d∅E through a small area element dA will be-
Electric flux is a scalar quantity. SI unit of electric flux is N-m²/C.
Dimensional formula is [ML³T⁻³A⁻¹].