This article discusses about examples of electromagnetic waves. As in the name suggests, the electromagnetic waves are related to both electricity and magnetism.
In this article we will be studying about different types of waves. After that we shall carry our discussion further to electromagnetic waves and its examples. Let us start with our discussion on electromagnetic waves first.
- Radar waves
- Solar energy
- Heat sensors
- Imaging bone structures
- Kill bacteria
- Used to observe visible world
What are electromagnetic waves?
Electromagnetic waves, the name itself suggests that these waves are related to both electricity and magnetic field.
These waves are formed by the vibrations taking place between electric and magnetic field. These type of waves constitute of oscillating electric field and magnetic field. We shall study more about waves in later sections of this article.
Types of waves
There are many types of waves. These are waves are sorted into two main groups of waves. The two main types of waves are given below-
- Transverse waves– Transverse waves are those waves which oscillate along a path perpendicular to the direction of wave propagation. EM waves, ripples in water etc are some examples of transverse waves.
- Longitudinal waves– Waves in which the medium vibrates parellely to the direction of wave propagation. The direction in which the medium is displaced has the same direction as that of direction of wave propagation.
Electromagnetic waves types
Even electromagnetic spectrum is divided in to seven other sub types. The classifiaction of these waves is done on the basis of their frequencies.
The different types of electromagnetic waves are given in the section below-
- Gamma rays– The frequency range of gamma rays is >3×10^17 Hz and wavelength range is <1nm.
- X rays– The frequency range of X rays is 3×10^16-3×10^17 and the wavelength ranges from 1 to 10 nm.
- Ultraviolet rays– The frequency range of ultraviolet rays is 7.5×10^14-3×10^16 and the wavelength ranges from 10 to 400 nm.
- Visible light- The frequency range of visible light is 4.3 x 10^14-7.5×10^14 and the wavelength ranges from 400 to 700 nm.
- Infrared– The frequency range of infrared waves is 3×10^12 to 4.3×10^14 and the wavelength ranges from 700 to 10^5 nm.
- Microwave– The frequency range of microwaves is 3×10^9 to 3×10^12 and the wavelength ranges from 10^5 to 10^8 nm.
- Radio waves– The frequency range of radio waves is <3×10^9 and the wavelength range is >10^8 nm.
Electromagnetic waves example
Electromagnetic waves are used in everyday applications. Some of the examples where electromagnetic waves are used are given in the section given below-
Radar waves are used to detect enemy vessel near our vicinity. These waves are emitted by RADAR and are reflected back after striking to the enemy vessel. This vessel can be aircraft or submarine or any other human equipped vessel.
UV rays are used to generate electricity using solar panels. These rays after striking the panel generate an EMF inside the panel. A capacitor can then store the generated electricity. Night vision- Infrared waves are used to see objects during night time. Night vision camera and goggles are used for security purposes to catch thieves/ terrorists roaming in the dark.
Heat sensors also use infrared waves. The heat spectrum is variable for different objects. Different objects emit different amounts of heat, this spectrum can be observed by using infrared waves.
Microwaves are used for heating food inside the microwave ovens. Even radar uses microwaves. Food is heated instantly after microwaves strike the food.
Radio waves are used for audio transmission by FM stations. They use these radio waves to broadcast their content.
Television sets also use radio waves for the transmission of their content. We can see different shows on television with the help of these waves.
Imaging bone structures
X rays are used for imaging bone structures. These rays penetrate inside the human body and strikes the bones giving a luminiscent images of the same.
Gamma rays are used for killing bacterias in marshmallows and to sterilise medical equipments.
Used to observe visible world
Visible light spectrum is used by humans to see the world around us. Without this spectrum, we won’t be able to see objects around us.
Electromagnetic waves in the order of increasing wavelength
We have discussed in the above sections that EM waves are divided into seven types according to their frequency/wavelengths.
The different types of EM waves in increasing order is given in the section below-
Gamma ray, X ray, UV rays, Visible light, infrared rays, microwaves and radio waves.
How are electromagnetic waves formed?
Electromagnetic waves are the waves which are related to both electric field and magnetic field. These waves are produced with the help of both the types of fields.
When magnetic field and electric field come in contact with each other, electromagnetic waves are formed. Both magnetic and electric fields make ninety degrees with each other as well as to the direction of propagation of wave.
How are electromagnetic waves propagated?
There are different media of propagation of electromagnetic waves. These are given in the section below-
- Ground waves– When the electromagnetic waves are transferred along the surface then it is called as ground wave propagation.
- Space waves– When the electromagnetic waves travel through vacuum of space, then that type of propagation is called as space wave propagation. Light from sun and other stars travel using this mode of propagation.
- Sky waves– Sky waves uses the principle of reflection. When electromagnetic waves are transmitted from the ground and are reflected back after striking ionosphere, then this type of propagation is known as sky wave propagation.
Properties of electromagnetic waves
The different properties of electromagnetic waves are given below-
- These waves move with the speed of light.
- These waves are transverse in nature, meaning the electric fields and magnetic fields are perpendicular to each other and the direction of wave propagation.
- These waves can undergo interference and diffraction.
- The EM waves cannot be deflected by electric field or magnetic field.
- It is not necessary for a medium to exist for propagation of these waves. These waves can travel without the help of medium also.