Question

What is meant by electric flux? Write its S.I. unit and dimensional formula.

Answer 1

Electric Flux: Electric flux is a number of electric lines of forces which posses through any cross sectional area when the cross sectional area in kept perpendicular to the direction of electric field.
Electric flux is scalar quantity which is denoted by ${\Phi }_E$.
S.I. Unit is Neutron($metr{e}^2$/ coulomb)
$N{\dot{M}}^2/C$
Dimensional Formula $=\frac{M^1{L}^1{T}^2\cdot L^2}{AT}$
$=\frac{M^1{L}^3{T}^{-2}{T}^2}{AT}=M^1{L}^3{T}^{-2}{T}^{-}1A^{-1}$
$=M^1{L}^3{T}^{-3}{A}^{-1}$
Formula of electric flux: Electric flux associated with any surface is defined as the dot produced or scalar.
electric field vector $\left(\overrightarrow{E}\right)$ and Aerial vector $\left(\overrightarrow{ds}\right)$ of that surface.

$d\Phi E=\overrightarrow{E}\cdot \overrightarrow{d}$

The angle between the direction of electric field vector and direction of aerial vector $\left(\overrightarrow{ds}\right)$ then according a the product of two vectors equation (1) can be written as.

$d\Phi =Edscos\theta$.