Magnetic Flux: Overview, Questions, Preparation

Magnetic flux is referred to as the total magnetic field (B) passing through a particular area of surface (A). it is denoted by the general formula: $\varphi =\vec{B}\cdot d\vec{A}=BdA\mathrm{c}\mathrm{o}\mathrm{s}\theta$

Where,

Φ = Magnetic Flux

B = Magnetic Field

A = Surface Area

$\theta$  = angle between $\vec{B}$ and the area vector $d\vec{A}$

Note:

1. If magnetic field is perpendicular to A, the formula will be:

ΦB​=B⋅A (because $\theta =0andcos\theta =1)$

2. If magnetic field is parallel to A, the formula will be:

ΦB​=0 (because $\theta =90andcos\theta =0)$

Flux is the trigger for electromagnetic induction. Magnetic flux helps us understand the impact of magnetic field over the desired surface, which helps us calculate the electromagnetic induction. Just as the electric flux helps to gain knowledge related to electricity, magnetic flux helps us gather insights of magnetic field’s influence over the area. Without magnetic flux, it will not be possible to generate electric current from magnetic properties since these two technologies combined are helpful in providing resources to the humankind. Both these principles allow us to design electrical devices such as motors, inductors, generators, transformers, etc. Electromagnetic induction acts as a bridge for connecting these two mechanisms and utilizing them to their full potential that has helped bring a revolution in the field of science.

Magnetic Flux mainly depends on the following factors:

1. Magnetic Field Strength (B): A stronger magnetic field will mean greater amount of magnetic flux.
2. Surface Area $(\mathit{A}$ ) : A larger surface area will consist of more field lines which will eventually lead to greater magnetic flux.
3. Angle between B and perpendicular $\left(\mathbf{c}\mathbf{o}\mathbf{s}\mathit{\theta }\right)$ : If $\vec{B}$ is perpendicular to the surface $\left(\theta =0^{\circ }\right),\mathrm{c}\mathrm{o}\mathrm{s}0=1$ , and the flux is maximum ( $\varphi =BA$  ). If $\vec{B}$  is parallel to the surface $\left(\theta ={90}^{\circ }\right),\mathrm{c}\mathrm{o}\mathrm{s}90=0$ , and flux will be zero.

Magnetic flux is the backbone of electromagnetic induction, and it’s combination with electric flux has led to development of various new technologies and inventions which have modernized our way of living. Here are some common examples:

• Induction Motors
• Electric Generators
• MRI devices
• Magnetic Sensors
• Transformers
• Wind Turbines
• Hydro Power plants
• Magnetic Circuits
• Faraday’s Law
• Wireless Communication