Nature of light
"The nature of light is still one of the fundamental puzzle of science" ( J.W.N Sullivan)
Light is a form of energy. It affects the eye so as to produce the sensation of vision. Vision is perhaps man's most valued gift of nature. Many natural phenomena not only inspire us by their beauty but also helps us to understand the nature of light e.g dispersion, interference, diffraction, polarisation,photoelectric effect etc.
Following theories have been enunciated by some of the physicsts about light.
Carpuscular theory:
Newton believed that light consist of tiny and discrete particles called carpuscles, a luminous body emits carpuscles in all directions with tremendous speed. He explained rectilinear propagation, reflection, refraction, transmission and absorption of light. But he failed to explain interference, diffraction and polarization and other properties of light.Newton's theory dominated for more than 100 years and took precedence over Huygens' wave front theory, partly because of Newton’s great prestige.
image source
When the corpuscular theory failed to adequately explain the diffraction, interference and polarization of light it was abandoned in favour of Huygens' wave theory. To some extent, Newton's corpuscular (particle) theory of light re-emerged in the 20th century, as light phenomenon is currently explained as particle and wave.He predicted that light would travel faster in a material medium e.g glass than in vacuum or air (proved wrong) .Newton concluded that telescope based on mirrors should be superior to one with lenses beause of their chromatic abberation ( he did not use that term, of course). He built a prototype but it was not better because his mirror suffered from spherical abberation.
Wave theory:
In 1678 the dutch scientist Christian Huygens a contemporary of Newton showed that light consist of waves. According to him a luminous body is a source of disturbance( mechanical waves) in a hypothetical medium " ether" .
image source
Later Fresnel developed this theory. Properties like rectilinear propagation, reflection, refraction, dispersion, interference and diffraction all can be explained with the help of this theory. However it failed to explain photoelectric emission and Compton effect. But on the basis of this theory it was explained that the speed of light in a denser medium e.g glass is lower than the speed of rare medium e.g air. This is in accordance with the experimental results of Foucault and Michelson.He fought Newton tooth and nail about the nature of light. He lost the fight. Newton appealed to the "Royal Society", the topmost authority in those bygone times, and 1715 it ruled that Newton's point of view was the correct one. This was not as stupid as it appears now. Huygens, as we know now, was right but could not really prove his assertions then.
Electromagnetic Theory:
In 1873 Maxwell showed that light is a form of high frequency electromagnetic wave. It consist of an oscillating electric field and an oscillating magnetic fields. Both the fields are oscillating perpendicular to each other.
image source
The direction of propagation of wave is perpendicular to both of the fields.Visible light is a small range of (4000°A to 7000°A) wavelength of the large electromagnetic spectrum.
image source
This theory explained all the properties of light. But it failed to explained photo-electric emission, compton effect etc.Maxwell's electromagnetic theory of light propagation eventually paved the way for a number of major technological innovations.The first and possibly most significant of these occurred in 1888, when Heinrich Hertz used Maxwell's theory to create instruments capable of sending and receiving radio pulses.This discovery, contributed to the creation of the television and the microwave and without Maxwell's tireless efforts, many of the modern conveniences upon which society has come to depend would not exist.As such, James Clerk Maxwell truly is the champion of modern day science.
Quantum Theory:
In 1900, Planck proposed that radiations are emitted and absorbed in the form of discrete bundles of energy of electromagnetic waves called quanta. The energy carried by each quanta is given by
image source
In 1905 Einstein showed that quantum of light also called photon behaves like particles. He succesfully explained photoelectric emission, later compton effect was also explained on the basis of quantum theory.Quantum theory is the theoretical basis of modern physics that explains the nature and behavior of matter and energy on the atomic and subatomic level.
References:
image source
The nature and behavior of matter and energy at that level is sometimes referred to as quantum physics and quantum mechanics.
https://en.m.wikipedia.org/wiki/Corpuscular_theory_of_light
https://www.tf.uni-kiel.de/matwis/amat/admat_en/kap_5/advanced/t5_1_1.html
https://www.azooptics.com/Article.aspx?ArticleID=944
http://whatis.techtarget.com/definition/quantum-theory
The nature of light is a captivating realm in physics, exploring the dual nature of particles and waves. Described by quantum theory, light can exhibit both particle-like photons and wave-like interference patterns. Understanding its behavior has profound implications in various scientific and technological domains. To delve deeper into the intricate facets of light, click here and embark on a fascinating journey through its properties and the fundamental principles that govern its existence.
@eileenbeach has voted on behalf of @minnowpond. If you would like to recieve upvotes from minnowpond on all your posts, simply FOLLOW @minnowpond. To be Resteemed to 4k+ followers and upvoted heavier send 0.25SBD to @minnowpond with your posts url as the memo
@cmtzco has voted on behalf of @minnowpond. If you would like to recieve upvotes from minnowpond on all your posts, simply FOLLOW @minnowpond
@minnowpond1 has voted on behalf of @minnowpond. If you would like to recieve upvotes from minnowpond on all your posts, simply FOLLOW @minnowpond. To be Resteemed to 4k+ followers and upvoted heavier send 0.25SBD to @minnowpond with your posts url as the memo
@originalworks
The @OriginalWorks bot has determined this post by @shehzad to be original material and upvoted it!
To call @OriginalWorks, simply reply to any post with @originalworks or !originalworks in your message!
To enter this post into the daily RESTEEM contest, upvote this comment! The user with the most upvotes on their @OriginalWorks comment will win!
For more information, Click Here! || Click here to participate in the @OriginalWorks sponsored writing contest(125 SBD in prizes)!
Special thanks to @reggaemuffin for being a supporter! Vote him as a witness to help make Steemit a better place!
This post recieved an upvote from minnowpond. If you would like to recieve upvotes from minnowponds team on all your posts, simply FOLLOW @minnowpond.