Magnetic Flux

Basic Electrical Engineering > Electricity and Magnetism > Magnetism

What is Magnetic Flux?

Magnetic flux is a measure of the amount of magnetic field passing through a given surface (such as a conducting coil).

It gives the measurement of the total magnetic field that passes through a given surface area. Here, the area under consideration can be of any size and under any orientation with respect to the direction of the magnetic field.

Fig.no.1: Magnetic flux

Magnetic Flux Symbol

Magnetic flux is commonly denoted using greek letter Phi ($\Phi _B$).

Magnetic Flux Formula

Magnetic flux formula is given by: $$ \Phi _B = B.A=BAcos\theta$$ Where, $\Phi _B$ is the magnetic flux.
B is the magnetic field.
A is the area
$\theta$, the angle at which the field lines pass through the given surface area.

Magnetic Flux Unit

The unit of the magnetic flux is the tesla meter squared (T. m2, also called the weber - the SI unit of magnetic flux and symbolized Wb). The older units for the magnetic flux, the Maxwell (equivalent to $10^{-8}$ Wb).