The wave theory of light was proposed by christiaan huygens. The wave is the value of the thing that is waving at every point in space and time. So, you can think of two light beams as two distinct light waves, or you can think of this situation as one wave that is the sum of the two individual beams. Electromagnetic waves and interference physics science. Even more important, though only touched on in this book, is the wave phenomenon of quantum mechanics, built into the fabric of our space and time. Here are some wave formulas that are useful when youre working with optics. Light is the common name for electromagnetic radiation with wavelengths of 400750 nm. Youngs double slit experiment shows clearly that light is a wave.
At this stage you should get a basic understanding of the wave model of light, which involves the idea of light as a complex superposition of many component waves, or elementary waves, each with its own wavelength. Ray diagrams show what happens to light in mirrors and lenses. Explain diffraction and interference in terms of huygens principle. Electromagnetic wave with constantly changing electric and magnetic fields that behaves as both a particle and a wave in the range of 400700 mm light transmission translucent transmits light with distortion. This chapter is essentially an introduction to the wave theory of light. Wave optics describes the connection between waves and rays of light. Dec 11, 2003 the wave is the value of the thing that is waving at every point in space and time. The text is designed for upperlevel undergraduate students with a physics background. His theory, along with detailed analysis of any cases. Like all electromagnetic waves, light can travel through a vacuum. In order to observe the wave behavior of light, the slit size and separation should be comparable or smaller than the wavelength of light. Huygens stated that light is made up of waves that vibrates up and down and is perpendicular to the direction of light.
The relation of the quantum to the wave theory of light would remain a point of puzzlement. Dec 16, 2015 syllabus for b sc general in physics the. Light consists of very tiny, elastic, rigid particles known as corpuscular. If youre behind a web filter, please make sure that the domains. Huygens put forward his wave theory according to which light energy propagated in the form of wave, with the help of wave theory he could successfully explain the phenomenon of reflection and refraction, interference and diffraction all. This theory is called huygens wave theory of light. S3p211 summarize the evidence for the wave model of light. Phys 201 lecture 18 wave theory of light open yale.
Physics notes for class 12 chapter 10 wave optics wave optics describes the connection between waves and rays of light. Study material 12th physics wave theory of light 1. For our purposes, in understanding how optical instruments work, the wave theory of light is entirely adequate. During fresnels talk, poisson pointed out that one of the. Quantum theory tells us that both light and matter consists of tiny particles which have wavelike properties associated with them. Its only when the mass of a particle gets small enough that its wavelike properties show up.
On the one hand the quantum theory of light cannot be considered satisfactory since it defines the energy of a light particle photon by the equation ehf containing the frequency f. Online query solving online mcq tests with detailedsolutions online notes and solvedexercises career counseling 2. Thomas young and the wave theory of light by riad haidar researcher at onera,1 lecturer at the ecole polytechnique thomas young is considered as a genius and polymath, a man who was equally gifted at languages and science. Pdf a reflection on theories of light researchgate. While it does not require a background in physics to understand, it is assumed that the reader has at least high school level linear algebra, calculus, and trigonometry. The physics classroom tutorial presents physics concepts and principles in an easytounderstand language. The wave nature of light was first illustrated through experiments on diffraction and interference. The wave theory of light is the sex of light as an electromagnetic wave. Light always piqued the curiosity of thinkers and scientists. Sound lies at the very center of speech communication. The distance between successive wave fronts is the wavelength. But this concept was not readily accepted and was in contradiction to the particle theory or the corpuscular theory of light proposed by sir isaac newton. Xii1002 wave theories of light 2016 pradeep kshetrapal. Planck was interested in the two theories that overlapped in this domain.
Over the next years einstein would only sharpen the. Instead, modern physics sees light as something that can be described. These solutions represent classical electromagnetic waves, which we know are somehow related to the quantum theorys photons. Since it classically is described by a wave but necessarily has particlelike properties. Quantum physics the wave structure of matter wsm and spherical standing wave interactions explains discrete energy states of quantum theory wave mechanics. Light waves vce the question of what is light was a matter of great debate during the 17th and 18th century. Light is composed of particles called photons, and matter is composed of particles called electrons, protons, neutrons.
In a sense wave mechanics is one step removed from this deeper theory in that the latter highlights the informational interpretation of quantum mechanics. The speed of light in a medium depends upon the nature of medium. In the study of optics, it is common to decompose complicated light fields into superpositions of pure sinusoidal waves. Christiaan huygens published his wave theory of light in 1690. Since it travels at the speed of light, c 3 108 m s. Insights into the foundations of quantum theory, including the waveparticle duality of light as. According to wave theory of light, the light is a form of energy which travels through a medium in the form of transverse wave motion. Learn about some of the mysterious properties of light in these tutorials. A sound wave is both the end product of the speech production mechanism and the primary source of raw material used by the listener to recover the speakers message. You may be aware by now that light is a form of energy. Light travels as transverse waves and faster than sound. Nov 10, 2018 class 12 chapter 10 ii wave optics 01. Conceptual ideas develop logically and sequentially, ultimately leading into the mathematics of the topics.
Here, in the article, let us discuss the wave theory of light in detail. He proposed that light is emitted as a series of waves in a medium called the luminiferous ether. Oct, 2017 the wave theory of light, proposed by dutch physicist christian huygens in 1678, has stood the test of time and is today considered one of the backbones of optics. Maxwells equations govern all of electricity and magnetism, so it is no surprise that they yield the wave equation. Other articles where wave theory of light is discussed. In this theory, light is represented as a spectrum of frequencies, some of which we can see visible light and some of which we cant ultraviolet and infrared light. Christian huygens proposed that light travelled as waves. A related proof offered in support of einsteins theory is the poundrebka experiment. Give a brief account of huygens wave theory of light. This is illustrated by the wave model of light and the particle model of light, which together describe the waveparticle duality in which light is understood to possess both wave and particle functions. I hope to emphasize that the physics of standing waves is the same. The physics of waves version date february 15, 2015. The wave theory and the particle theory of light were long considered to be at odds with.
In 1678, dutch physicist christian huygens proposed a theory to explain the wave nature of light. Sir isaac newton believed that light was a stream of particles. This confusion about the true nature of light continued for some years till a modern quantum theory of light emerged in which light is neither a wave nor a particle the new theory reconciles the particle properties of light with the wave nature. Fresnel, supported by ampere and arago, offered a paper in which he developed the scalar theory of diffraction in much the same way we did, based on the wave theory. Where one beam is zero, the total wave is just trivially the other beam. Describe the basic features of the wave model of light. He believed that light was a longitudinal wave, and that this wave was propagated through a material called the aether. Solving for the wave vector, we arrive at the dispersion relation for light in free space. State and apply the relation among wavelength, frequency and speed of a. The founder of physiological optics and father of the wave theory of light, he was also the first person to decipher a. The wave theory of light, proposed by dutch physicist christian huygens in 1678, has stood the test of time and is today considered one of the backbones of optics. Wave theory of light history, huygens propostions and more. Wave theory definition of wave theory by merriamwebster. Interference is described using real and complex numbers in anticipation of quantum mechanics.
Now a purely particle theory contains nothing that enables us to define a frequency. These waves were represented by the socalled wave function x. Light waves that is, electromagnetic waves behave like other waves. For some the answers crystallized with quantum mechanics, the result of a quartercenturys labor. These corpuscles on emission from the source of light travel in straight line with high velocity when these particles enter the eyes, they produce image of the object or sensation of vision. The transverse nature of light can be demonstrated through polarization. You can determine the wave frequency and period, predict how fast light travels in various materials, and determine how light. Wave theory of light classroom lecture by pradeep kshetrapal. Phys 201 lecture 18 wave theory of light open yale courses. The theory was spread most significantly by robert hooke and christiaan huygens in the 17th century. This experiment uses the concept of a freely falling body to predict a change in the. Eventually the modern theory of quantum mechanics came to picture light as in some sense both a particle and a wave, and in another sense, as a phenomenon which is neither a particle nor a wave which actually are macroscopic phenomena, such as baseballs or ocean waves. The wave theory of light was considered in terms of longitudinal waves so could not explain polarisation of light.
Topics covered include re ection and transmission at boundaries, dispersion, polarization e ects, di raction, coherence, ray optics and imaging, the propagation of light in matter, and the quantum nature of light. How light travels light waves ks3 physics revision. If youre seeing this message, it means were having trouble loading external resources on our website. Newtons corpuscular theory, wave theory of light, physics.
This confusion about the true nature of light continued for some years till a modern quantum theory of light emerged in which light is neither a wave nor a particle the new theory reconciles. Christiaan huygens, thomas young, augustin jean fresnel, franaois arago created date. The wave theory of light proposed by christian huygens has stood the test of time and today, it is considered the backbones of optics. They can reflect, refract bend, and interfere with each other. Describe the dual nature of light, as a continuous wave and a discrete particle photon, and give. The dutch astronomer huygens 16291695 proposed a wave theory of light. Interference of light waves and youngs experiment emedicalprep.
Quickly assess your understanding of what light is, and the history of those who worked on the wave theory of light, using this multiple choice quiz and worksheet. Definition of light before going into the wave theory of light, lets learn about light itself. In the seventeenth century two rival theories of the nature of light were proposed, the wave theory and the corpuscular theory. Now, not only is light an electromagnetic wave but so are. Each lesson includes informative graphics, occasional animations and videos, and check your understanding sections that allow the user to practice what is taught. Traveling waves appear only after a thorough exploration of onedimensional standing waves. The first was electr odynamics, the theory of electricity, magnetism, and light.
Light is a transverse, electromagnetic wave that can be seen by the typical human. The human eye is capable of detecting light, which distinguishes it from other regions of the electromagnetic spectrum despite having shared properties with light, most notably speed. This property forms the basis of the fields of optics and optical communications and a myriad of related technologies, both mature and emerging. The existence of a fundamental connection between light and gravity has already been established by the theory of general relativity. Augustin fresnel and the wave theory of light photoniques. How can it make sense to use the same word wave for all these disparate phenomena. This term is sometimes expanded to include ultraviolet and infrared radiation. Wondering how to integrate it with the powerful apparatus of nineteenthcentury physics, they also asked what relation it bore to existing, classical theories. Technological applications based on the manipulations of light include lasers, holography, and fibreoptic telecommunications systems in most everyday circumstances, the properties of light can. Electromagnetic radiation im going to redirect this stub over to a much more extensive.
395 1142 210 716 1381 1279 1208 539 698 1505 141 1280 1333 222 1329 999 1297 662 1478 85 78 1261 921 1040 1131 302 886 394 316 947 415 414 240 292 983 1493 201 382 929 346 1064 1437 485 917