An electromagnetic emission of a wavelength has been referred as light. In specific, visible light is an electromagnetic radiation that can be seen with a human naked eye. In a methodical and physical framework, the term light is utilized to refer the electromagnetic spectrum as a whole. In addition, photons are considered the elementary particles of the visible light. A number of properties have been come across during the analysis of the visible light, as the light has been the subject of many experts and scientists for various decades. In this regard, we will try to cover every theory that has been associated with the properties of light.
One of the most elementary properties of light is its intensity according to most of the physicists that have worked on the subject of the electromagnetic radiation of a wavelength. In terms of its definition, when the time-averaged vigor fluctuation is measured, the result is referred as the intensity. In non-professional terms, different terms like strength, level, etc. have been referred with the term of intensity; however, this has not been the case in the physical property of intensity of the light. For instance, a pressure cannot have intensity, as both variables are very much different in their properties.
Similarly, the light cannot be associated with the terms of level, strength, etc. In terms of calculation, velocity of energy is multiplied by the energy per unit volume, which results in the measurement of intensity. Moreover, the units of power are divided by the power to denote the resulting vector of intensity, i-e, watt/m2. The term of intensity has mostly been taken for defining the property of waves; however, the water can also be considered for the defining of intensity, but most of the scientists have considered the utilization of intensity for the waves specifically. (Akins, pp. 29-31)
Another major property of light is the frequency. Most of the experts have analyzed that it is a determination of the quantitative incidences of a recurring occurrence per unit time. Other scientists have referred frequency as a temporal frequency. The phase is the period of a single sequence in a recurring occurrence. Therefore, the phase is the reciprocal of the frequency, which is one of the major characteristics of the most of the electromagnetic waves, especially the visible light.
Most of the waves go through different recurring and cyclic progressions. In this regard, the visible light also goes through different cycles during its travelling. In definition, the unit time has been considered the standard for the counting of cycles of periods that is referred as the frequency. In physical science and associated disciplines, a Latin letter ‘f’ has been considered the standard symbol for denoting the frequency. In some circumstances, letter ‘v’ is used for the same purpose, and is pronounced ‘new’. (Bassetto, pp. 23-24)
In the measurement system of SI, hertz (Hz) is the standard unit of frequency. In specific, Heinrich Hertz has been one of the prominent physicists of all the time, who has been given tribute by the referral of his surname as a unit of frequency. Therefore, frequency of light is always measured in hertz (Hz). For instance, if an occurrence of visible light is occurred in one second, the frequency of light is 1 hertz (Hz). Similarly, if one second has two repeated events, then the frequency will be 2 hertz (Hz), and so. In previous decades, frequency was known as a cycle per second, and the unit was cps. Still, a number of physicists apply this unit during the defining of frequency of light in some circumstances.
The conception of wavelength has an inverse relationship with the frequency. Thus, wavelength is inversely proportional to the wavelength, which is denoted by the symbol ‘λ’. In order to calculate the frequency of light, the wavelength is considered for the division of speed of the light wave, which is denoted by letter ‘v’. Therefore, f = v / λ. In other circumstances such as moving of light waves in vacuum, the speed of light in a vacuum is denoted by c, and c is equal to v. In such circumstances, the frequency can be calculated by the division of c with λ, and the equation is written as f = c / λ. (Waldman, pp. 73-75)
Another significant characteristic of the light waves is Polarization. The direction of the fluctuations on the flat surface at right angles to the direction of travel of light waves has been described and defined as the Polarization. A number of physicists have considered the polarization as one of the important properties of different waves, especially the light waves. The concept of polarization plays a vital and crucial role in the proliferation of light waves according to a number of scientists around the world that are working in different areas of science and technology.
Some of the major fields of science and technology that has utilized the polarization property of light waves are telecommunications, optics, seismology, etc. In the field of electrodynamics, electromagnetic waves are differentiate and characterized by the property of polarization. In this regard, the light waves are significantly distinguished by the polarization. In specific, the electric field of light waves is specified by a proper direction with the help of polarization. (Reynolds, pp. 55-58)
The plan electromagnetic wave is usually visualized by the easiest demonstration of polarization. In other words, most of the light waves can be visualized due to its property of polarization. In addition, most of the light waves have long, as well as, wide wavelengths that are mostly infinite in measurements, which results in their consideration as plane waves. It has been observed by most of the scientists that the direction of proliferation is always at right angles to the electric and magnetic fields of electromagnetic waves, especially light waves when they travel in vacuum or any free space.
Conservatively, the description of electric field vector is given importance, whereas, the magnetic field is ignored at the time of considering the polarization property of light waves. One of the reasons of ignoring magnetic filed is its vertical direction to the electric field. During the analysis of polarization, two perpendicular components can be acquired by the division of electric field vector in an arbitrarily manner. (Sweetnam, pp. 49-56)
In nature, electromagnetic emission is frequently created by a huge amount of character supplies, which results in the production of independent waves in the space. This kind of light has been referred as incoherent by most of the physicists. Generally, different frequencies create a spectrum, and a single frequency cannot be attained in such light. Moreover, a reliable state of polarization was not attained, even after the filtration of such light to a narrow range of frequency in an arbitrarily manner. However, it should not be considered that the coherent radiation has only feature of polarization.
The constituents of an electric field confront a statistical correlation between them due to the incoherent radiation. This kind of provision of correlation of components has been referred as partial polarization by most of the experts. In general, when a completely polarized element is combined with a completely incoherent part, a wave field is attained that can be taken as the sum of the abovementioned two elements. In this way, the degree of polarization can be considered for the description of light and light ways. Moreover, the parameters of polarization ellipse can also be used for the similar description. (Harrison, pp. 34-36)
Extremely widespread applications have been observed in the modern technology that has utilized the property of polarization of light waves. Perhaps, liquid crystal displays (LCDs), as well as, polarized sunglasses are some of the common and most appreciated examples of the modern technology that has used the property of polarization of light wave. Another prominent example is the television that uses horizontal polarization property of the light.
Nowadays, photography is using the polarizing filters for the better presentation of the pictures. Reflection from windows or standing water can be eliminated easily, as well as, the color of blue sky can be altered and deepened by the polarizing filters. Thus, the modern technology has applied this property of light in an effective and useful manner. (Rossing, pp. 22-24)
Wave Particle Duality
Interestingly, characteristics of both waves, as well as, particles can be exhibited by the light waves, which is an important property of the light. The physicists and chemists have referred such characteristic as wave-particle duality. In modern physics, the study of light has been referred as optics, which was commenced from the discovery of this property of the light waves.
In physics and chemistry, when properties of both waves, as well as, particles can be exhibited by the matter, it is known as the wave-particle duality characteristics of that matter. In this regard, the fundamental theory of quantum mechanics has been considered for the description of wave-particle duality characteristic, as the behavior of objects can be fully described by the addressing of properties of waves and particles. Thus, this apparent and perceived inconsistency has been explained by the different considerations related to the quantum mechanics in physics. (Zubrowski, pp. 41-46)
The proposal of duality is entrenched in a discussion regarding the nature of light waves, as well as, other matter that dates back to the 1600s. In 1600s, some of the eminent physicists like Christian Huygens, Isaac Newton, etc. played a vital role in the development of concepts related to the light waves by the proposition of a number of theories related to the nature of light waves.
Moreover, it is now considered that characteristics of a wave is hold by all the particles of nature, which was possible due to the efforts of a number of scientists and physicists like Albert Einstein, Louis de Broglie, etc. In addition, compound particles likes molecules and atoms also possess the similar property of wave-particle duality. In this regard, light also possess the property of wave-particle duality based on such concept in the modern physics.
For a long period, light possessed the only characteristic of wave-nature, as a number of experiments have resulted in the provision of similar nature of the light. The wave-like nature of the light was clearly demonstrated by experiments, such as double-slit experiment of Thomas Young, and the experiment of diffraction by physicist, Fraunhofer that provided the similar results.
However, a number of problems were confronted by most of the physicists during the commencement of twentieth century. In the year 1905, the particle-like characteristics of light was demonstrated, as the photoelectric effect was analyzed by Albert Einstein. Subsequently, in the year 1923, the Compton Effect further confirmed the wave-particle duality property of the light. (Lorentz, pp. 36-38)
Speed of Light
In physics, 186,282.397 miles per second is the speed of light when the light wave is passing through the vacuum. Moreover, the travelling medium plays a vital role in the determination of speed of light. For instance, a transparent medium results in the lower speed of light, as compared to an opaque one. In the determination of speed of light, the magnitude and direction plays a crucial role in the definition of velocity, as the speed of light is commonly refer as velocity of light.
However, the magnitude of velocity is only included in the definition of speed of light. In this regard, application of modern physics has taken a number of steps to acquire a fixed definition of the speed of light. One of the examples of efforts of modern physics is the consideration of speed of light for the defining of unit of length, which contradicts to the practice of earlier physics that used the unit of length for the defining of speed of light.
A number of physicists have endeavored to calculate the speed of light all the way through history. One of the examples of such physicists is Galileo, who attempted the calculation of the speed of light in the seventeenth century. Moreover, one of the prominent Danish physicists, Ole Romer conducted a good experimentation for the calculation of the speed of light in the year 1676. In this experiment, the movements of a planet Jupiter and one of its moons was observed with the help of utilization of a telescope.
During this experimentation, it was estimated that the light wave navigate the diameter of orbit of Earth in approximately eighteen minutes. Unfortunately, that estimation was not appropriate, which was confirmed by the physicists of modern physics. If the diameter of earth’s orbit would have been known by Ole Romer, a speed of 227,000,000 m/s has been the calculated speed of light. (Akins, pp. 70-71)
In the year 1849, another physicist, Hippolyte Fizeau conducted an experiment for the calculation of speed of light. During this experiment, a mirror was used to direct a beam of light several kilometers away from Fizeau. The path of the beam of light confronted a rotating cogwheel, and the light was allowed to reach the mirror and then returned to its origin.
It was found out by Fizeau that a gap was passed by the beam of light, and when the light was returning back, it passed through another gap of the cogwheel. As the information related to the distance of the path, the distance of mirror and source, mirror and wheel, etc. was known by Fizeau, the calculation of speed of light was found to be 313,000,000 m/s. ((Bassetto, pp. 33-35)
In the year 1862, speed of light as 298,000,000 m/s was obtained by the utilization of rotating mirrors during an experiment by Leon Foucault. Similar experiments were conducted by Albert A. Michelson who preferred utilization of improved rotating mirrors from the year 1926 to the year 1931 for the calculation of speed of light. In the year 1926, the methods that were used by Foucault were refined by Albert. In this experiment, the location of Mt. Wilson to Mt. San Antonio was considered for the determination of speed of light. In the result, a speed of 299,796,000 m/s of light were yielded by Albert in his experiments.
When the speed influences a change in the direction of a wave, it has been referred as Refraction. Light waves possess this property, as its speed results in the changes of direction at different intervals. Moreover, when a wave passes through different mediums, the refraction can be observed in these waves. In this regard, the refraction is most common example in the light waves, as light waves are mostly manipulated by the concept of refraction. In specific, Snell’s law has described the concept of refraction as the relation of angle of refraction with the angle of incidence. (Reynolds, pp. 87-88)
In the field of optics, traversing of light waves from one medium to another results in the occurrence of refraction. Moreover, an alteration can be observed in the velocity of light wave, as it passes the boundary of one medium to enter into another.
In the result, the direction of light wave changes, and an increment or reduction is observed in the wavelength of light wave. However, it has been observed that frequency has no effect from the refraction property of the light wave. For instance, when a light ray passes through a glass, one can observe refraction easily. Some of the eminent and important discoveries and inventions are the lenses, as well as, the refracting telescope that have been invented on the concept of refraction of light. ((Zubrowski, pp. 59-63)
Another common example of refraction property of light can be demonstrated with a bowl of water. About 1.0003 is the refractive index of air, and 1.33 is the refractive index of water particles. If a straight object like pencil or straw is brought in front of a person with half of its part in the water, one can easily notice a bend in the part that is placed in the water.
One of the reasons of the bending visibility is the refraction property of light that results in the bending of light rays while it passed from the medium of air to the medium of water. Moreover, the term of apparent depth has been used to determine the depth of another medium like water from the above view. One of the frequent examples is the spear fishing that requires the fisher to determine the exact place of a fish, as the fish would be at a different place, as compared to the place of fish that will be visible from the above. (Goldstein, pp. 63-65)
Rainbow is another major example of refraction that can be easily noticed by a nonprofessional. A white light is split into a spectrum of rainbow, as a glass prism is put into the path, which is due to the refraction of light. One of the reasons of splitting of white light is due to the refractive index of air, which is lower that the refractive index of glass. While natural stunning appearances like rainbows are formed by the refraction of light, unusual optical occurrences can also be produced with the property of refraction of light.
Some of the examples of such irregular phenomena are Fata Morgana, mirages, etc. All these phenomena are achieved by the changes in the refractive index of temperature, as well as, the air. Imagination of a marching band, as they passes through one medium of pavement to another medium of mud, can explain the refraction of light in a useful manner. The closer side that turns into the mud first will have to slow down first, which results in the slight rotation of the whole band. This is an effective example to understand the property of refraction of light. (Waldman, pp. 96-99)
In the field of medicine, refraction of light has contributed a lot in the areas of ophthalmology and optometry. The concept of refraction of light is used, as the refractive error of human eye is determined by the utilization of phoropter in a clinical test, which is referred as refraction. In the result, prescription of corrective contact lenses is provided to the patient.
The sharpest and clearest vision is attained by the utilization of lenses of different focal lengths and optical powers. (Isaacson, pp. 60-66) Thus, the property of refraction of light has changed the lives of millions of people around the world due to the application of modern physics. In this regard, the light has different properties that have been discussed and analyzed in this paper in a detailed manner. It is hoped that this paper will help students, experts, physicists, etc. in the better understanding of properties of light, as well as, its application in the modern physics and technology that has affected the millions of human lives around the world.
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