# What is Electromagnetic Spectrum? Explained

In addition to the ray we see with our eyes, there are many rays in the universe that are not visible to the naked eye. To study all those rays, based on their differences in frequency and wavelength, a scientific scale system called electromagnetic spectrum (EMS) has been created.

1. What is Electromagnetic Spectrum?
b) Microwaves
c) Infrared rays
d) Visible light
e) Ultraviolet rays
f) X-rays
g) Gamma rays

# What is Electromagnetic Spectrum?

Usually, the human eye sees only visible lights that come from the lamp and seen in rainbow such as Violet, Indigo, Blue, Green, Yellow, Orange & red light. But there are also some lights around us or from space that are not visible to the human eyes, such as Radio waves, Microwaves, Infrared rays, Ultraviolet rays, X-rays, Gamma rays. These are all kinds of electromagnetic radiation.

All these electromagnetic radiations are plotted according to the intensity of light at different frequency ranges or distribution of wavelength and frequency. This range in the distribution of wavelength and frequency of all types of electromagnetic radiation is called the electromagnetic spectrum.

Radio waves are a type of electromagnetic radiation that is best known for their use in communication technologies, such as television, mobile phones, and radios. These types of waves are also emitted by astronomical objects ( such as stars, gases, etc ) in space and recorded by scientists through telescopes.

If we talk about the wavelength of Radio waves then radio waves have the longest wavelengths in the electromagnetic spectrum.  Yes, radio waves have wavelength range from the length of a football to larger than our planet.

Radio waves have wavelengths ranging from 1 millimeter (mm) to 10,000 kilometers (km)s. At 1 millimeter (mm), the corresponding frequency is approximately 300 gigahertz (GHz), and at wavelength 10,000 kilometer (km) the corresponding frequency is approximately 30 hertz (Hz).

## Microwaves

Microwaves are a type of electromagnetic radiation that is best known for its use in cooking food in microwave ovens. Also, microwaves have a range of applications, including spacecraft communications, radar, satellite,  radio astronomy, particle accelerators, spectroscopy, industrial heating, etc. Astronomers used these waves to learn about the structure of nearby galaxies.

If we talk about the wavelength of microwaves, then it has wavelengths ranging from 1 millimeter (mm) to 1 meter (m). At 1 millimeter (mm), the corresponding frequency is approximately 300 gigahertz (GHz), and at wavelength 1 meter (m) the corresponding frequency is approximately  300 megahertz (MHz).

## Infrared Rays

Infrared rays are a type of electromagnetic radiation (EMR) with wavelengths longer than those of visible light. That is why it is usually invisible to the human eye. But we feel the heating effect of it. For this, it can be used as a deliberate heating source. Today infrared heating is becoming more and more popular in industrial manufacturing processes, for example - in curing of coatings, forming of plastics, annealing, plastic welding, and print drying, etc.

Infrared has a range of applications, including wireless communication, spectroscopy, and weather forecasting. The household uses like TV remote control that shoots the IR power pulses of the IR receiver from the light-emitting diode (LED) to the TV, relying on infrared radiation.

Infrared rays have wavelengths ranging from 700 nanometers (nm)s to 1 millimeter (mm). At 700 nanometers (nm)s, the corresponding frequency is approximately 430 terahertz (THz), and at wavelength 1 millimeter (mm) the corresponding frequency is approximately 300 gigahertz (GHz).

## Visible light

Visible light rays are a type of electromagnetic radiation (EMR) that is visible to the human eye. That is why it has a special significance for us. In the electromagnetic spectrum (EMS), the neighbors of visible light are such as infrared radiation on one side and ultraviolet radiation on the other side.

Visible light rays have wavelengths ranging from 380 nanometers (nm)s to 740 nanometers (nm)s. At 380 nanometers (nm)s, the corresponding frequency is approximately 405 terahertz (THz), and at wavelength 740 nanometers (nm)s the corresponding frequency is approximately 790 terahertz (THz).

A typical human eye responds to wavelengths ranging from about 380 nanometers (nm) to 740 nanometers (nm)s. That is why we can see this light. We see these lights as the colors of the rainbow. Although each color has a different wavelength.

## Ultraviolet rays

Ultraviolet rays are a type of electromagnetic radiation (EMR) whose wavelength is shorter than visible light but longer than that of X-rays. Ultraviolet rays have wavelengths ranging from 10 nanometers (nm)s to 400 nanometers (nm)s. At 10 nanometers (nm)s, the corresponding frequency is approximately 30 petahertz (PHz), and at wavelength 400 nanometers (nm)s the corresponding frequency is approximately 750 terahertz (THz).

Ultraviolet (UV) radiation reside in sunlight and constitutes about 10% of the total electromagnetic radiation output from the Sun. Too much exposure to UV radiation present in the sunlight is damaging to living tissue. For which the Earth's atmosphere is made up of ozone layers that help protect organisms from these extra ultraviolet rays.

But the use of these ultraviolet rays in science is essential. Ultraviolet rays have a range of applications, including Photography, Therapy, Sterilization, and disinfection. Ultraviolet rays are also used in the electrical, and electronics industries.

## X-rays

X-rays are a type of electromagnetic radiation (EMR) that is capable of penetrating materials (including biological tissue) and ionizing gases. It is similar to light but with extremely short wavelengths and high frequency.

X-rays have wavelengths ranging from 10 picometres (pm) to 10 nanometres (nm)s. At 10 picometres (pm), the corresponding frequency is approximately 30 petahertz (PHz), and at wavelength 10 nanometres (nm)s the corresponding frequency is approximately 30 exahertz (EHz).

## Gamma rays

Gamma rays are a type of electromagnetic radiation (EMR) that comes from the radioactive decay of atomic nuclei. It has the shortest wavelengths and the maximum energy of any rays in the electromagnetic spectrum. Gamma-rays have wavelengths of less than 100 picometers (pm)s, and frequencies greater than about 10^19 cycles per second, or hertz (Hz).

Gamma rays have the relatively strong penetrating power of matter that is why  Ernest Rutherford named this radiation as gamma rays. Gamma rays have a range of applications, including Gamma-ray therapy, Gamma-ray astronomy.