What is electromagnetic radiation and how they are useful for society ?

Electromagnetic radiation is a form of energy. Oxford Language Dictionary says; Electromagnetic radiation is” a kind of radiation including visible light, radio wave, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously.”

What is electromagnetic radiation?

Electromagnetic radiation is a form of energy. Oxford Language Dictionary says; Electromagnetic radiation is” a kind of radiation including visible light, radio wave, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously.”

Light is a form of energy, that travels in the form of electromagnetic waves. These waves are made up of electrical and magnetic vectors, which are perpendicular to each other and travel in the direction of propagation. Photons are tiny particles that comprise the wave of electromagnetic radiation.

In 1860 physicist James Clerk Maxwell of Scotland propounded the electromagnetic theory of light, which changed the perception and understanding of light. Michel Faraday’s conception of electric and magnetic effects laid the foundation for Maxwell’s theory. He exhibited that photons are electric fields, that travel through space. In quantum theory, electromagnetic radiation is a flow of photons.

German physicist Max Karl Planck in 1900 suggested that light is emitted in bundles or packets instead of a steady stream. This packet of light is referred to as quantum(photon) and each quantum is proportional to its frequency.

The wavelength of light varies with the nature of light. The shorter the wavelength the higher the frequencies. The frequencies and wavelengths are proportional to each other. However, all the light waves travel at the same velocity as light in space/vacuum.

Types of electromagnetic waves.

Electromagnetic waves are seven types and from longest to smallest wavelengths are as such; radio waves, microwaves, Infrared radiation, visible light, ultra violate radiation, X-rays, and Gamma rays, and energy increases with the decrease of wavelengths.

Radio Waves:

A radio wave is a form of electromagnetic radiation, having the longest wavelength in the light spectrum. The Radio wave length is>1×10-1 meter and frequencies <3×109 Hz. German physicist Heinrich Rudolph Hertz discovered the Radio wave in late 1880. Many natural, as well as man-made objects, emit radio waves.

It is a fact that anything that emits heat, emits radiation in the entire arena of the spectrum but in different quantities. Stars, planets, and other cosmic bodies emit radiation, and radio, television stations, and cell phone companies produce the radio waves for communications.

Radio waves are basically communication signals and are very useful in today’s world. But of radio, Television, and cell phones, radio waves are used in navigation, air traffic control, radio astronomy, remote control toys, and other purposes.

Microwaves:

Microwaves are the second lowest wave frequency in the electromagnetic spectrum. Wavelength varies from 1×10-3 to 1×10-1 meter, whereas wave frequencies vary between 3×109 to 3×1011 Hz. Microwaves are used in wireless networks, radars, satellites, remote sensing, radio astronomy, the treatment of cancer and cooking, etc.

Infrared radiation:

The wavelength of Infrared radiation is placed in between Microwaves and visible light. It is also referred to as thermal radiation. Wavelength varies between 7×10-7 and 1×10-3 meters and corresponds to frequencies ranging from 3×1011 to 4×1014 Hz. Infrared radiation is categorized as IR-A (780nm-1.4μm), IR-B(1.4-3μm), and IR-C(3μm-1mm).

Infrared radiation is used in industrial, scientific research, military, commercial and medical sectors. Some examples are electric heaters, cookers, remote controls, optical fibers, security systems, thermal imaging cameras, night vision devices, and cameras, etc.

Visible light:

Visible light is placed in such a spectrum of light, which is seen by human eyes. The wavelength varies from 4×10-7 to 7×10-7 in meters, corresponding to frequencies 4×1014 to 8×1014 cycles/second or Hz. From largest to shortest wavelength in color spectrum sequences are red, orange, yellow, green, blue, indigo, and violet.

Ultraviolet radiation:

The wavelength of Ultraviolet radiation is placed in between visible light and X-Ray and has low penetration power. Most parts of Ultra violate radiation coming from Sun are absorbed by the Ozone layer(O3) of the atmosphere and the rest escapes, affecting humans’ skin. UV radiation wavelength varies between between1x10-8 to 4×10-7 meters, corresponding to frequencies; 7.5×1014 to 3x1016Hz. UV radiation is divided into three bands, such as UVA(315-400nm), UVB(280-315nm) UVC(100-280nm). UV radiation is used in the industrial and mostly in medical sectors for the treatment of diseases like cancer and for diagnosis.

X-Ray or X-Radiation:

An X-Ray is a form of high-energy electromagnetic radiation, a wavelength placed between UV radiation and Gamma Rays. Wavelength varies from 1×10-11 to 4×10-8meter, corresponding to frequencies in the range of 3×1016 to 3×1019 Hz and energies in the range of 2×10-17 to 2×10-14Hz. Used in medical applications and security purposes. In medical applications, X-Ray penetrates into the applied bodies to take images of internal parts, boons, etc, which were not visible to physicians for diagnosis and killing of cancer cells.

Gamma Ray:

Gamma Ray is a penetrating form of electromagnetic radiation with high frequencies and smallest wavelength and the highest energy. Gamma Rays are produced in nature by neutron stars, supernova explosions, lightning, and in the periphery of black holes.

It is also obtained by the decay of an atomic nucleus artificially in a reactor. Gamma Rays are more penetrating in the matter and can damage living cells on a big scale if exposed to them. “Wavelengths are so short that, they can pass through the space within an atom of a detector,” says NASA.

Wavelengths are <1×10-11meter, and frequencies are >3×1019 Hz. Gamma Rays are utilized in industries for sterilization and disinfection in the medical sector for the diagnosis, and treatment of cancers( radiotherapy, oncology) like diseases. It is also used in astronomy and nuclear industries.

Conclusion:

Light has both electrical and magnetic properties. Further, light is a form of energy and travels in the form of electromagnetic waves. These waves are made up of electrical and magnetic vectors, which are perpendicular to each other and travel in the direction of propagation. Waves have frequencies to their proportionate. Highest the wave length lowest the frequency and vice versa and energy increase at the decrease of wavelengths.