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A sub-discipline of physics in the field of electromagnetism is the magnetic flux through a surface, which refers to the surface integral of the magnetic field’s (B) normal component passing through that surface. To be specific, magnetic flux is defined as the number of magnetic field lines passing through a given closed surface. In this particular scenario, the area under consideration can be in any orientation corresponding to the direction of the magnetic field and of any size.
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Symbol and Formula of Magnetic Flux
Magnetic flux are denoted by the Greek letter Phi and have the symbol [Phi or Phi _{B}].
To calculate the magnetic flux, we can use the formula given below:
[ Phi _{B} = B. A = B A cos Phi ]
Where,
[ Phi _{B} ] = Magnetic Flux
B = Magnetic Field
A = Area
[ Phi ] = Angle at which the magnetic field lines pass through the given surface area
Fluxmeter is used to measure the magnetic flux.
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SI Unit of Magnetic Flux
Weber (Wb) is the SI unit of magnetic flux, which is named after Wilhelm Eduard Weber, a German physicist. A flux density of one Weber per square meter or [Wb/m^{2}] is one Tesla, denoted by T (explained in the next section). Quite often, Weber is expressed in a multitude of other units, as shown below:
[Wb = kg m^{2}/s^{2} A = V.s = H.A = T.m^{2} = J/A = 10^{8}Mx]
Where, Wb = Weber, T = Tesla, V = volt, m = metre, J = joule, s = second, H = Henry, A = ampere, and Mx = Maxwell.
CGS unit of Magnetic Flux
The CGS unit of magnetic flux is Maxwell (Mx) or Abweber (abWb).
Fundamental Unit of Magnetic Flux
The fundamental unit of magnetic flux is Volt-seconds.
Understanding the Term Magnetic Flux Density
The force acting per unit length on a wire placed perpendicular (at right angles) to the magnetic field per unit current is the magnetic flux density (B).
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Tesla (T) or [ Kg s^{-2} A^{-1}] is the SI unit of magnetic flux density (B).
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The magnetic flux density, denoted by the symbol B, is a vector quantity
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The CGS unit of magnetic flux density is Gauss, which is abbreviated as G or Gs
The formula for calculating the magnetic flux density is as follows:
B = F/I L
Where
F = total force acting on the wire
I = current flowing through the wire
L = length of the wire
Submultiples of Weber(Wb)
|
Value |
SI Symbol |
Name |
|
10-1 Wb |
dWb |
deciweber |
|
10-2 Wb |
cWb |
centiweber |
|
10-3 Wb |
mWb |
milliweber |
|
10-6 Wb |
µWb |
microweber |
|
10-9 Wb |
nWb |
nanoweber |
|
10-12 Wb |
pWb |
pico weber |
|
10-15 Wb |
fWb |
femto weber |
|
10-18 Wb |
aWb |
attoweber |
|
10-21 Wb |
zWb |
zepto weber |
|
10-24 Wb |
yWb |
yocto weber |
Multiples of Weber
|
Value |
SI Symbol |
Name |
|
101 Wb |
daWb |
decaweber |
|
102 Wb |
hWb |
hector weber |
|
103 Wb |
kWb |
kiloweber |
|
106 Wb |
MWb |
mega weber |
|
109 Wb |
GWb |
gigaweber |
|
1012 Wb |
TWb |
teraweber |
|
1015 Wb |
PWb |
Peta weber |
|
1018 Wb |
EWb |
exaweber |
|
1021 Wb |
ZWb |
zettaweber |
|
1024 Wb |
YWb |
yotta weber |
Magnetic Flux
It can be defined as the total number of magnetic field lines which pass through a given closed surface. This quantity provides a measurement for the total magnetic field in a given area. The areas we take into consideration are of different sizes and different orientations considering the magnetic field direction. It is generally measured using a flux meter. There are different units for flux. In the SI unit, it is Weber which is abbreviated as Wb. The CGS unit that is used for this is Maxwell and the unit used fundamentally is Volt-Seconds. Thus, it is a measurement of the total magnetic field that passes through an area we take into consideration. It is a very good tool that can be used for finding the magnetic force on an area. It is related to the area chosen and we can choose an area of any size and arrange it according to the magnetic field.
Faraday conducted his experiment on electromagnetic induction and gave insights on the mathematical relation related to it. He made many contributions to science and was known greatly in the [19^{th}] century for his scientific contributions. Magnetic flux plays a major role in the process of electromagnetic induction. In order to calculate this quantity, we take into consideration the field-line image of a magnet or many magnets present.