# Electric Flux by A.K.Sinha

Electric Flux:

Electric Flux is a measure of total electric field lines crossing a particular area. we can simply define it as dot product of Electric field and Area vector. It is represented by Φ such that Here ds is an area vector.

( NOTE : The first equation in fig. represents dot product of two vectors and when we simply that equation we get the very next equation.)

Electric flux depends on the cosine of angle between electric field and area vector.

When E is along area vector i.e. θ =0°, Flux is Maximum & Φ = E ds , and when E is perpendicular to the area vector i.e. θ = 90°, Flux is Minimum & Φ = 0.

Electric Flux is a Scalar quantity.

SI Unit : N m2 C-1

Area Vector:

In the concept of electric flux we consider area as a vector and consider its direction as perpendicular to  the plane of the area going outside. Here ds is a small area. And its direction is perpendicular to the plane of area ds.

Electric Flux Density :

Electric Flux Density is defined as the field lines produced across closed unit area.

Q.1) If a body gives out 105 electrons every second, how much time is required to get a total charge of 1 C from it ?

Q.2) Two equal and opposite charges of 2 × 10-7 C  are placed 1 mm apart. Find the magnitude and nature of force of interaction.

1. 