Self Propagating Waves In A Vacuum Biology Essay
According to the concepts of electro medicine most of the diseases are caused by micro organisms. Electromagnetic radiation having many hazardous effects on human beings and other living forms has the other side of having disease curing effect. The killing and destructive power of electromagnetic radiation can be used constructively for curing the incurable diseases by eradicating the disease producing pathogens and micro organisms like bacteria, virus & fungi. Here the mechanism of shattering a wine glass with high pitch sound by an opera singer by the resonance principle is used for destroying the micro organism. This paper deals with the modes of curing the difficult to treat diseases like cancer, the principles involved, machines used and limitations encountered.
Electromagnetic radiationÂ (often abbreviatedÂ E-M radiationÂ orÂ EMR) is aÂ phenomenonÂ that takes the form ofÂ self-propagatingÂ wavesin aÂ vacuumÂ or inÂ matter. It consists ofÂ electricÂ andÂ magnetic fieldÂ components whichÂ oscillateÂ in phase perpendicular to each other and perpendicular to the direction of energyÂ propagation. Electromagnetic radiation is classified into several types according to thefrequencyÂ of its wave; these types include (in order of increasing frequency and decreasing wavelength):Â radio waves,Â microwaves,terahertz radiation,Â infrared radiation,Â visible light,Â ultraviolet radiation,Â X-raysÂ andÂ gamma rays.
We can help you to write your essay!
Shows three electromagnetic modes (blue, green and red) with a distance scale in micrometres along the x-axis
Electromagnetic wavesÂ were first postulated byÂ James Clerk MaxwellÂ and subsequently confirmed byÂ Heinrich Hertz. Maxwell derived aÂ wave form of the electric and magnetic equations, revealing the wave-like nature of electric and magnetic fields, and their symmetry. Because the speed of EM waves predicted by the wave equation coincided with the measuredÂ speed of light, Maxwell concluded thatÂ lightÂ itself is an EM wave.
According toÂ Maxwell's equations, a spatially-varyingÂ electric fieldÂ generates a time-varyingÂ magnetic fieldÂ andÂ vice versa. Therefore, as an oscillating electric field generates an oscillating magnetic field, the magnetic field in turn generates an oscillating electric field, and so on. These oscillating fields together form an electromagnetic wave.
AÂ quantum theoryÂ of the interaction between electromagnetic radiation and matter such as electrons is described by the theory ofÂ quantum electrodynamics.
Electromagnetic wavesÂ can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. This diagram shows a plane linearly polarized wave propagating from right to left. The electric field is in a vertical plane, the magnetic field in a horizontal plane.
TheÂ physicsÂ of electromagnetic radiation isÂ electrodynamics, a subfield ofelectromagnetism. Electric and magnetic fields obey the properties ofsuperpositionÂ so that a field due to any particular particle or time-varying electric or magnetic field will contribute to the fields present in the same space due to other causes: as they areÂ vectorÂ fields, all magnetic and electric field vectors add together according to vector addition. For instance, a travelling EM wave incident on an atomic structure induces oscillation in theÂ atomsÂ of that structure, thereby causing them to emit their own EM waves,Â emissionsÂ which alter the impinging wave through interference. These properties cause various phenomena includingÂ refractionÂ andÂ diffraction.
In refraction, a wave crossing from one medium to another of differentÂ densityÂ alters its speed and direction upon entering the new medium. The ratio of the refractive indices of the media determines the degree of refraction, and is summarized by Snell's law. Light disperses into a visibleÂ spectrumÂ as light is shone through a prism because of the wavelength dependent refractive index of the prism material.
EM radiation exhibits both wave properties andÂ particleÂ properties at the same time. Both wave and particle characteristics have been confirmed in a large number of experiments. Wave characteristics are more apparent when EM radiation is measured over relatively large timescales and over large distances while particle characteristics are more evident when measuring small timescales and distances.
Upon absorption of light, it is not too difficult to experimentally observe non-uniform deposition of energy. Strictly speaking, however, this alone is not evidence of "particulate" behavior of light, rather it reflects the quantum nature ofÂ matter
There are experiments in which the wave and particle natures of electromagnetic waves appear in the same experiment, such as the self-interference of a singleÂ photon.Â TrueÂ single-photon experiments can be done today in undergraduate-level labs.Â
An important aspect of the nature of light isÂ frequency. The frequency of a wave is its rate of oscillation and is measured inÂ hertz, theÂ SIÂ unit of frequency, where one hertz is equal to one oscillation perÂ second. Light usually has a spectrum of frequencies which sum together to form the resultant wave. Different frequencies undergo different angles of refraction.
A wave consists of successive troughs and crests, and the distance between two adjacent crests or troughs is called theÂ wavelength. Waves of the electromagnetic spectrum vary in size, from very long radio waves the size of buildings to very short gamma rays smaller than atom nuclei. Frequency is inversely proportional to wavelength, according to the equation:
whereÂ vÂ is the speed of the wave,Â fÂ is the frequency and Î» is the wavelength. As waves cross boundaries between different media, their speeds change but their frequencies remain constant.
InterferenceÂ is the superposition of two or more waves resulting in a new wave pattern. If the fields have components in the same direction, they constructively interfere, while opposite directions cause destructive interference.
This essay is an example of a student's work
The energy in electromagnetic waves is sometimes calledÂ radiant energy.
Electromagnetic radiation has particle-like properties as discrete packets of energy, orÂ quanta, calledÂ photons.Â The frequency of the wave is proportional to the particle's energy. Because photons are emitted and absorbed by charged particles, they act as transporters ofÂ energy. The energy perÂ photonÂ can be calculated from theÂ Planck-Einstein equation:
whereÂ EÂ is the energy,Â hÂ isÂ Planck's constant, andÂ fÂ is frequency. This photon-energy expression is a particular case of the energy levels of the more generalÂ electromagnetic oscillatorwhose average energy, which is used to obtain Planck's radiation law, can be shown to differ sharply from that predicted by theÂ equipartition principleÂ at low temperature, thereby establishes a failure of equipartition due to quantum effects at low temperature.
As a photon is absorbed by anÂ atom, it excites anÂ electron, elevating it to a higherÂ energy level. If the energy is great enough, so that the electron jumps to a high enough energy level, it may escape the positive pull of the nucleus and be liberated from the atom in a process calledÂ photoionisation. Conversely, an electron that descends to a lower energy level in an atom emits a photon of light equal to the energy difference. Since the energy levels of electrons in atoms are discrete, each element emits and absorbs its own characteristic frequencies.
Together, these effects explain the emission and absorption spectra ofÂ light. The dark bands in the absorption spectrum are due to the atoms in the intervening medium absorbing different frequencies of the light. The composition of the medium through which the light travels determines the nature of the absorption spectrum. For instance, dark bands in the light emitted by a distantÂ starÂ are due to the atoms in the star's atmosphere. These bands correspond to the allowed energy levels in the atoms. A similar phenomenon occurs forÂ emission. As the electrons descend to lower energy levels, a spectrum is emitted that represents the jumps between the energy levels of the electrons. This is manifested in theÂ emissionÂ spectrum ofÂ nebulae. Today, scientists use this phenomenon to observe what elements a certain star is composed of. It is also used in the determination of the distance of a star, using theÂ red shift.
Speed of propagation
Any electric charge which accelerates, or any changing magnetic field, produces electromagnetic radiation. Electromagnetic information about the charge travels at the speed of light. Accurate treatment thus incorporates a concept known asÂ retarded time which adds to the expressions for the electrodynamicÂ electric fieldÂ andÂ magnetic field. These extra terms are responsible for electromagnetic radiation. When any wire (or other conducting object such as anÂ antenna) conductsalternating current, electromagnetic radiation is propagated at the same frequency as the electric current. At the quantum level, electromagnetic radiation is produced when the wavepacket of a charged particle oscillates or otherwise accelerates. Charged particles in aÂ stationary stateÂ do not move, but a superposition of such states may result in oscillation, which is responsible for the phenomenon of radiative transition between quantum states of a charged particle.
Depending on the circumstances, electromagnetic radiation may behave as aÂ waveÂ or asÂ particles. As a wave, it is characterized by a velocity,Â wavelength, and frequency. When considered as particles, they are known asÂ photons, and each has an energy related to the frequency of the wave given byÂ Planck'sÂ relationÂ E = hÎ½, whereÂ EÂ is the energy of the photon,Â hÂ = 6.626 Ã- 10âˆ’34Â JÂ·s isÂ Planck's constant, andÂ Î½Â is the frequency of the wave.
One rule is always obeyed regardless of the circumstances: EM radiation in a vacuum always travels at theÂ speed of light,Â relative to the observer, regardless of the observer's velocity. (This observation led toÂ Albert Einstein's development of the theory ofÂ special relativity.)
In a medium,Â velocity factorÂ orÂ refractive indexÂ are considered, depending on frequency and application. Both of these are ratios of the speed in a medium to speed in a vacuum.
electromagnetic radiation as a form of heat
The basic structure ofÂ matterÂ involves charged particles bound together in many different ways. When electromagnetic radiation is incident on matter, it causes the charged particles to oscillate and gain energy. The ultimate fate of this energy depends on the situation. It could be immediately re-radiated and appear as scattered, reflected, or transmitted radiation. It may also get dissipated into other microscopic motions within the matter, coming toÂ thermal equilibriumÂ and manifesting itself as thermal energy in the material. With a few exceptions such asfluorescence,Â harmonic generation,Â photochemical reactionsÂ and theÂ photovoltaic effect, absorbed electromagnetic radiation simply deposits its energy by heating the material. This happens both for infrared and non-infrared radiation. Intense radio waves can thermally burn living tissue and can cook food. In addition to infraredÂ lasers, sufficiently intense visible and ultraviolet lasers can also easily set paper afire. Ionizing electromagnetic radiation can create high-speed electrons in a material and break chemical bonds, but after these electrons collide many times with other atoms in the material eventually most of the energy gets downgraded to thermal energy, this whole process happening in a tiny fraction of a second. That infrared radiation is a form of heat and other electromagnetic radiation is not, is a widespreadÂ misconceptionÂ in physics.Â AnyÂ electromagnetic radiation can heat a material when it is absorbed.
Earn money as a Freelance Writer!
We’re looking for qualified experts
As we are always expanding we are looking to grow our team of freelance writers. To find out more about writing with us then please check our freelance writing jobs page.
The electromagnetic radiation in an opaque cavity at thermal equilibrium is effectively a form of thermal energy, having maximumÂ radiation entropy.
The Wave Nature of Light
The Electromagnetic SpectrumÂ :The Electromagnetic Spectrum Electromagnetic waves vary depending on frequency and wavelengthÂ
Properties of the Electromagnetic SpectrumÂ :Properties of the Electromagnetic Spectrum Waves in the electromagnetic spectrum vary in size from very long radio waves the size of buildings, to very short gamma-rays smaller than the size of the nucleus of an atom. Did you know that electromagnetic waves can not only be described by their wavelength, but also by their energy and frequency? All three of these things are related to each other mathematically. This means that it is correct to talk about the energy of an X-ray or the wavelength of a microwave or the frequency of a radio wave. The electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, X-rays, and gamma-rays.Â
Different Frequencies and WavelengthÂ :Different Frequencies and Wavelength In visible light, the differences in frequency and wavelength account for the different colors. Just as red light has its own distinct frequency and wavelength, so do all the other colors. Orange, yellow, green, and blue each exhibit unique frequencies and consequently wavelengths. While we can perceive these electromagnetic waves in their corresponding colors, we cannot see the rest of the electromagnetic spectrum. The differences in wavelength and frequency also distinguishes visible light from invisible electromagnetic radiation, such as X Rays.Â
Frequencies for different colorsÂ :Frequencies for different colors Every electromagnetic wave exhibits a unique frequency, and wavelength associated with that frequency. For instance, this picture represents an electromagnetic wave corresponding to the color red. Its frequency is 428 570 GHz, which can also be stated as 428,570 billion cycles per second. So when you look at red light, your eye receives over four hundred trillion waves every second!Â
Visible SpectrumÂ :Visible Spectrum ROYGBIV= Red, Orange,Yellow, Green, Blue, Indigo, VioletÂ
Different types of wavesÂ :
Different types of waves Radio Waves- longest wavelength. AM/FM, TV Microwaves- 2nd longest wavelength. Radar, Microwaves Infrared Waves- 3rd longest wavelength. Infrared photography, night vision Visible Light- 4th longest wavelength. Microscope, astronomy Ultraviolet Light- 5th longest wavelength. Sterilization X Rays- 6th longest wavelength. Medical exam of teeth and bones Gamma Rays- Shortest wavelength. Used in cancer treatment and food irradiationÂ
Radio WavesÂ :
Radio Waves Radio waves have the longest wavelengths in the electromagnetic spectrum. These waves can be longer than a football field or as short as a football. Radio waves do more than just bring music to your radio. They also carry signals for your television and cellular phones. Objects in space, such as planets and comets, giant clouds of gas and dust, and stars and galaxies, emit light at many different wavelengths. Some of the light they emit has very large wavelengths - sometimes as long as a mile! These long waves are in the radio region of the electromagnetic spectrum.Â
Microwaves Microwaves have wavelengths that can be measured in centimeters! The longer microwaves, those closer to a foot in length, are the waves which heat our food in a microwave oven. Microwaves are good for transmitting information from one place to another because microwave energy can penetrate haze, light rain and snow, clouds, and smoke. Because microwaves can penetrate haze, light rain and snow, clouds and smoke, these waves are good for viewing the Earth from space.Â
Infrared LightÂ :
Infrared Light Infrared light lies between the visible and microwave portions of the electromagnetic spectrum. Far infrared waves are thermal. In other words, we experience this type of infrared radiation every day in the form of heat! The heat that we feel from sunlight, a fire, a radiator or a warm sidewalk is infrared. Shorter, near infrared waves are not hot at all - in fact you cannot even feel them. These shorter wavelengths are the ones used by your TV's remote control. To make infrared pictures like the one below, we can use special cameras and film that detect differences in temperature, and then assign different brightnesses or false colors to them. This provides a picture that our eyes can interpret.Â
Visible Light WavesÂ :
Visible Light Waves Visible light waves are the only electromagnetic waves we can see. We see these waves as the colors of the rainbow. Each color has a different wavelength. Red has the longest wavelength and violet has the shortest wavelength. When all the waves are seen together, they make white light. When white light shines through a prism, the white light is broken apart into the colors of the visible light spectrum. Water vapor in the atmosphere can also break apart wavelengths creating a rainbow. Cones in our eyes are receivers for these tiny visible light waves. The Sun is a natural source for visible light waves and our eyes see the reflection of this sunlight off the objects around us. The color of an object that we see is the color of light reflected. All other colors are absorbed.Â
Ultraviolet WavesÂ :
Ultraviolet Waves Ultraviolet (UV) light has shorter wavelengths than visible light. Though these waves are invisible to the human eye, some insects, like bumblebees, can see them! Scientists have divided the ultraviolet part of the spectrum into three regions: the near ultraviolet, the far ultraviolet, and the extreme ultraviolet. The three regions are distinguished by how energetic the ultraviolet radiation is, and by the "wavelength" of the ultraviolet light, which is related to energy. Our Sun emits light at all the different wavelengths in electromagnetic spectrum, but it is ultraviolet waves that are responsible for causing our sunburns. Though some ultraviolet waves from the Sun penetrate Earth's atmosphere, most of them are blocked from entering by various gases like Ozone. Some days, more ultraviolet waves get through our atmosphere. Scientists have developed a UV index to help people protect themselves from these harmful ultraviolet waves.Â
X-Rays When you get an X-ray taken at a hospital, X-ray sensitive film is put on one side of your body, and X-rays are shot through you. Because your bones and teeth are dense and absorb more X-rays then your skin does, silhouettes of your bones or teeth are left on the X-ray film while your skin appears transparent. Many things in space emit X-rays, among them are black holes, neutron stars, binary star systems, supernova remnants, stars, the Sun, and even some comets!Â
Gamma RaysÂ :
Gamma Rays Gamma-rays have the smallest wavelengths and the most energy of any other wave in the electromagnetic spectrum. These waves are generated by radioactive atoms and in nuclear explosions. Gamma-rays can kill living cells, a fact which medicine uses to its advantage, using gamma-rays to kill cancerous cells. Gamma-rays are the most energetic form of light and are produced by the hottest regions of the universe. They are also produced by such violent events as supernova explosions or the destruction of atoms, and by less dramatic events, such as the decay of radioactive material in space. Things like supernova explosions (the way massive stars die), neutron stars and pulsars, and black holes are all sources of celestial gamma-rays.Â
Speed of Electromagnetic WavesÂ :
Speed of Electromagnetic Waves All electromagnetic waves move at the speed of light Rememberâ€¦ Speed= wavelength x frequency Only the wavelength and frequency change This change decides which type of electromagnetic wave it is (radio, gamma, etc.)Â
Speed of LightÂ :
Speed of Light The speed of light in a vacuum= 2.99792458 x 108 m/s The speed of light in air= 2.99709 x 108 m/s We use 3 x 108 m/s which equates to 300 million meters per second!Â
Astronomy and the SpectrumÂ :
Astronomy and the Spectrum By studying the electromagnetic emissions of objects such as stars, galaxies, and black holes, astronomers hope to come to a better understanding of the universe. Although many astronomical puzzles can only be solved by comparing images of different wavelengths, telescopes are only designed to detect a particular portion of the electromagnetic spectrum. Astronomers therefore often use images from several different telescopes to study celestial phenomena. Shown on the next slide is the Milky Way Galaxy as seen by radio, infrared, optical, X-ray and gamma-ray telescopes.Â
Milky Way Galaxy as seen by different rayed telescopes: Milky Way Galaxy as seen by different rayed telescopes From top to bottom: Radio, Infrared, Visual, X Ray, and Gamma Rays.
Polarizations of Electromagnetic Radiation
Electromagnetic radiation is a term used to describe a stream of energy-bearing particles that travels outward from an electromagnetic source. The energy in these streams can vary extensively in power, and is measured by the electromagnetic spectrum. Electromagnetic radiation can be beneficial, harmless or extremely dangerous to humans, depending on the source, level of radiation, and duration of exposure.
There are both natural and man-made sources of electromagnetic radiation. The sun, for instance, is an intense source of radiation that can have both positive and negative effects on living things. The sun also produces both visible and invisible electromagnetic streams.Â Ultraviolet raysÂ from the sun are invisible and cause sunburn and skinÂ cancerÂ if overexposure occurs. A rainbow, however, is a visible and harmless part of the electromagnetic effect caused by the sun, as human eyes detect the visible wavelengths of light as different colors.
Man-made sources of electromagnetic radiation includeÂ X-rays,Â radio waves, and microwaves, although some natural sources exist as well. Microwaves and radio waves are used by humans to power machines and increase communication abilities. Cell phones, radios, microwave ovens, and and radar all create electromagnetic radiation. This has lead to some concern that the growing prevalence of electromagnetic devices will lead to large increases in illnesses caused by radiation, such as cancer. As of yet, few studies suggest that exposure to household devices is strong enough to causeÂ genetic mutationÂ or cancer.
Scientists break down electromagnetic radiation into two types, non-ionizing and ionizing. Non-ionizing varieties include visible radiation,Â infraredÂ radiation, and most types of low-energy radiation like radio and microwaves. Overexposure to non-ionizing radiation can cause burns to the skin, but is unlikely to cause genetic mutation or alter cellular structure. Ionizing radiation, such as that used in cancer treatments, is made up of high-energy wavelengths and can actually alter or mutateÂ DNA. While this can be used to treat cell-affecting diseases like cancer, it can also cause serious and possibly fatal cellular damage leading to birth defects orÂ radiation sickness.
The power contained in electromagnetic radiation can be both helpful and destructive to humans. Although it has become a vital part of technology, it also remains an enormousÂ liabilityÂ to human health. Overexposure to radiation, whether in an acute dose or a slow, continual intake, can quickly lead to illness and even a painful death. However, as electromagnetic radiation is also a natural part of the human environment, exposure to some radiation is unavoidable.
Electromagnetic radiation for Food preservation-pros and cons
It's being used all over the world from commonly processed foods to organic foods. I just can't help to think "microwaved food" when I think about electromagnetic radiation. So I'm curious as to what this may mean when it comes to the quality of our food. Microwaved food has shown to be striped of nutrients. (I feel you may as well be eating Mickey D's). Does electromagnetic radiation for Food preservation do the same thing or is it truly a cure all? Will I get the full potential of an organic grown product not treated with this radiation vs. the food that is?
Solar energy is free of pollution.
The plant requires little maintenance or help after setup.
It is economical.
When it is connected to the grid, solar energy can overtake the highest cost electricity at peak demand and can also reduce grid loading, apart from getting rid of the need for local battery power in darkness.
It is available only by day and not when the sky is cloudy, thereby reducing the chances of it being totally reliable and requiring storage facilities.
It needs a backup power plant to be kept hot and to replace solar power stations as they stop producing energy.
Keeping backup plants hot includes an energy cost which includes coal burning.
Places located at high altitudes or those that are often cloudy are not targets for solar power use.
It can only be used to power transport vehicles by converting energy into another form of energy and recurring an energy penalty.
Solar cell technologies produce DC power which needs to be converted to AC power, incurring an energy penalty.
Solar energy can be used to generate electricity using photovoltaic solar cells and concentrated solar power, apart from other means. You can use solar power in the house for domestic use.
Raymond chang, Modern chemistry of +2
If you are the original writer of this essay and no longer wish to have the essay published on the UK Essays website then please click on the link below to request removal: