Electric flux, the property of an electric field. It can be also defined as the rate of flow of the electric field through a given area.
Electric flux is proportional to the number of electric field lines.
Conditions:
- If the electric field is uniform, the electric flux passing through a surface of vector area S is
ΦE =E⋅S =ES cos θ
where E is the magnitude of the electric field.
S is the area of the surface
θ is the angle between the electric field lines and normal to S.
- For non-uniform electric field, the electric flux dΦE.
- through a small surface, area dS is given by
dΦE =E⋅dS
(the electric field, E, multiplied by the component of area perpendicular to the field).