Electric Flux

Electric Flux

What is meant by electric flux and What is electric flux formula? Define electric flux class 12.

Electric flux definition or Electric flux meaning: Electric flux is the rate of flow of an electric field through an area. Electric flux is proportional to the number of electric field lines passing through a virtual surface. The physical quantity to measure the strength of the electric field and frame the basics of electrostatics.

Uniform Electric Field:

Formula of electric flux or Flux Equation: The electric flux passing through surface of vector area A is


where E is an electric field

A is the area of the surface and

is the angle between the electric field lines and normal to A.

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Non Uniform Electric Field: The flux d E through a small surface area dA is

d E=EdA

where,d E is an electric flux for a non-uniform electric field.

Gauss Law:

The net outward normal electric flux through any closed surface is proportional to the electric charge enclosed in a closed surface. Gauss Law is known as Gauss Flux Theorem, and it is a law which relates the distribution of charge (electric) to the produced electric field. The electric flux over a surface A is given by a surface integral;


If the electric flux isn’t affected by charges which aren’t within a closed surface. The E in the Gauss-Law equation is affected by charges which lie outside a closed surface. While Gauss Law detains all situations, it is only beneficial for “in hand” calculations when high degrees of symmetry exist in the electric field.

What is magnetic flux? Define magnetic flux physics.

Magnetic flux definition and Magnetic flux, meaning: Magnetic flux refers to the total number of magnetic field lines penetrating any surface placed perpendicular to the magnetic field. The overall magnetic field that traverses across a specific area is determined by magnetic flux . It's a valuable tool for identifying the effects of magnetic force on things in a particular location.

In physics, generally electromagnetic induction, the magnetic flux throughout the surface integration of the normal component of the magnetic field B over a surface is the magnetic flux throughout that surface. It is commonly indicated by the symbol ∅ or ∅B. The SI unit of magnetic flux is Weber (Wb), while Maxwell is the CGS unit.

The magnetic interaction is characterized as a vector field, in which each point in space is designated, a vector that indicates the force that a moving charge will encounter at that position. Because a vector field is difficult to interpret at first, field lines would be used to describe it in fundamental physics.

The number of field lines determines the magnetic flux through a surface that flows through it; the flux can be specifically defined as the number of field lines that pass through it. The magnetic flux is the difference between the number of field lines going through a surface in one direction and the number passing through it in the other direction.

The magnetic flux ∅ linked with a surface held in a magnetic field B is defined as the number of magnetic lines of force crossing a closed area. A. If is the angle between the field's direction and the area's normal, then



This electro-motive force is known as the induced electromotive force and the current that flows in the closed circuit is called the induced current.

The phenomenon of producing an induced electromotive force due to changes in the magnetic flux associated with a closed circuit is known as electromagnetic induction.

Observation of electric flux:

  1. Electric flux becomes zero, when the electric field is parallel to the surface area ΔS, as the angle becomes 90° and the value of cos 90° is zero.
  2. The direction of ΔS is determined by the area vector, as it has both magnitude and direction.
  3. Electric flux becomes negative when the electric field and area vector are antiparallel.
  4. The direction of the area vector is always out of the surface.

Applications of Electric flux

Electric flux helps in calculation of electric fields and Gauss Theorem, one of the most useful theorems of electrostatics, is based mainly on electrostatics.

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