Introduction

When electric and magnetic fields come in contact, electromagnetic waves are produced. And when these waves are combined, it gives rise to electromagnetic radiation. In other words, it is said that electromagnetic radiation is produced by oscillating magnetic and electric fields. In classical physics, electromagnetic radiation is energy flow through a material medium or free space. As they move at the speed of light, the two fields combine to form electromagnetic waves, more commonly known as em waves. Radio waves, gamma rays, and visible light come under electromagnetic waves. The direction of motion and the two fields are perpendicular in such waves. Let’s discuss some other important factors regarding em waves and the application of electromagnetic waves. 

Formation of Electromagnetic Waves 

When a charged particle produces an electric field, the produced electric field exerts the force on other particles leading to negative and positive charges. When these charges are accelerated, positive charges move in the direction of the electric field, whereas negative charges tend towards the magnetic field direction. 

In contrast, a magnetic field is produced by the charges in motion. Likewise, in the above step, the field exerts a force on the other moving charges, but the direction and velocity are always perpendicular. Remember, during this case, only the direction of the charges is changed, whereas speed remains constant. 

Electromagnetic waves, a combination of magnetic and electric fields, are produced by oscillating charged particles. When these fields accelerate in the free space with the velocity of light, the charged particle starts oscillating about its equilibrium position. The formula for electromagnetic waves is λ = c/f, where c is the speed of light, f is the frequency of oscillation of charged particles and λ is the wavelength. 

Properties of Electromagnetic Waves 

Here are a few properties of electromagnetic waves. 

1. These waves are transverse. 
2. The waves propagate by varying magnetic and electric fields. These two fields are perpendicular to each other; they make right angles. In addition to that, the fields are at right angles to the direction of wave propagation. 
3. They travel with constant velocity, that is, speed of light 3 x 108 m/s.
4. These waves are non-mechanical. Meaning they don’t require any material medium to propagate. 
5. Electromagnetic waves follow the rule λ = c/f or c = λf. No matter the wavelength or frequency,  their product always remains constant. 
6. The oscillating electric and magnetic fields phase is always the same. In addition to that, the amplitude ratio of both electric and magnetic fields is always equal to c. Here c represents the velocity of the EM wave. 

Types & Applications of E.M Waves 

Generally, there are seven types of electromagnetic waves. Here are the types, along with the application of electromagnetic waves. 

1. Radio waves – Lowest frequency waves, radio waves are used in the communication industry. They are used to carry the signals. In addition to that, each natural and artificial object emits radio waves. For instance, stars, planets, cosmic bodies, television, and radio stations emit radio waves. 
2. Microwaves – Next type of em waves is microwaves. Its frequency lies at the second last of the electromagnetic spectrum. With high frequency, microwaves are capable of penetrating obstacles and objects. Due to their penetrating nature, microwaves carry radar, computer data transmission, land-line phone calls, and much more. 
3. Infrared waves – Between microwaves and visible light lies infrared waves. The infrared radiations with high wavelengths are capable of producing more heat. In contrast, Infrared radiations with lower wavelengths produce less heat and are used in imaging technologies and remote controls. Additionally, they help capture the pictures during fog, smoke, and mist.
4. Visible light rays – We all know the visible light rays. The light visible to the naked eye or the light emitted by natural sources like the sun or artificial sources is mostly visible light. We see objects when they absorb light of a specific wavelength and emit light of another wavelength. 
5. Ultraviolet waves – They have shorter wavelengths that assist in studying molecular structures and help astronomers learn more about galaxies. 
6. X-rays – These waves come under the category of high-energy waves. The application of electromagnetic waves like X-rays is to view the bone structures in the human body. Additionally, X-Ray therapy is one of the best applications of X-rays. 
7. Gamma rays are used for medical purposes with high frequency and lower wavelengths. In addition to that, they have the power to detect faults, cracks, flaws, and holes in metals.

So this was all about the different em waves and the application of electromagnetic waves. 

Electromagnetic Wave Equation

The electromagnetic wave equation describes the propagation of electromagnetic waves through a material medium or vacuum. It is the second-order partial differential equation and is of 3D form. Additionally, the intensity of an electromagnetic wave is defined by the formula I = P/A, where P is power, and A is defined as area.  Electromagnetic waves are arranged according to their frequency or wavelength, λ = c/f.  These waves are arranged according to their wavelengths or frequencies in the electromagnetic spectrum. Here, the waves are arranged from a lower frequency to a higher frequency or higher or lower wavelength.

Conclusion 

Electromagnetic waves and the application of electromagnetic waves cover an essential aspect of physics. Numerous things use electromagnetic waves (as covered under the applications of em waves). Electromagnetic waves are composed of photons that pass through a material medium or vacuum. When these waves pass through the medium, some waves are reflected, whereas others are absorbed.