Electrical | Wikipedia audio article
Electricity. Is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge in. Early days electricity. Was considered as being not related to magnetism, later. On many experimental, results in the development of Maxwell's, equations indicated, that both electricity, and magnetism, are from a single phenomenon electromagnetism. Various. Common phenomena are related to electricity including, lightning static, electricity electric, heating electric, discharges, and many others, the. Presence of an electric charge which can be either positive or negative produces. An electric field the. Movement of electric charges is an electric current and produces, a magnetic field, when. A charge is placed in a location with a nonzero electric, field a force will act on it the. Magnitude, of this force is given by Coulomb's law thus, if the charge were to move the electric field would be doing work on the electric charge thus. We can speak of electric potential at a certain point in space which is equal to the work done by an external agent in carrying a unit of positive charge from an arbitrarily, chosen reference, point to that point without any acceleration and is typically measured in volts. Electricity. Is at the heart of many modern technologies, being used for, electric. Power where electric, current is used to energize equipment. Electronics. Which deals with electrical, circuits that involve active electrical, components, such as vacuum tubes transistors diodes and, integrated circuits, and associated. Passive interconnection technologies, electrical. Phenomena have been studied since antiquity though progress in theoretical understanding, remains slow until the 17th, and 18th centuries, even. Then practical, applications, for electricity, were few and it would not be until the late 19th, century that electrical, engineers were able to put it to industrial, and residential use the. Rapid expansion in electrical, technology at this time transformed, industry in society, becoming a driving force for the Second Industrial Revolution. Electricity's. Extraordinary, versatility, means it can be put to an almost limitless set of applications, which include transport, heating lighting communications. And computation. Electrical. Power is now the backbone, of modern industrial society. Topic. History. Long, before any knowledge of electricity existed, people were aware of shocks from electric fish ancient. Egyptian texts dating from 20 750, BCE referred, to these fishes the Thunderer. Of the nile and described. Them as the protectors. Of all other fish electric, fish were again reported, millennia later by ancient Greek Roman and Arabic natural ists and physicians, several. Ancient writers such as Pliny the Elder and screw bonus loggers attested, to the numbing effect of electric shocks delivered by electric, catfish and electric rays and knew that such shocks could travel along conducting, objects, patients. Suffering from ailments, such as gout or headache were directed to touch electric fish in the hope that the powerful jolt might cure them possibly. The earliest and, nearest approach to the discovery, of the identity, of lightning and electricity from, any other source is to be attributed to the Arabs who before the 15th century had the Arabic word for lightning rod rode applied to the electric ray ancient, cultures around the Mediterranean, knew that certain objects such as rods of amber could be rubbed with cat's fur to attract light objects like feathers Thales. Of Miletus made, a series, of observations, on static electricity around, 600, BCE from which he believed that friction rendered amber magnetic, in contrast, to minerals such as magnetite, which needed no rubbing fails. Was incorrect in believing the attraction, was due to a magnetic effect but later science would prove a link between magnetism, and electricity.
According. To a controversial, theory the Parthians may have had knowledge of electroplating. Based on the 1936. Discovery, of the Baghdad battery which, resembles, a galvanic cell though it is uncertain whether the artifact, was electrical, in nature. Electricity. Would remain little more than an intellectual curiosity for, millennia until 1600. When the English scientist William Gilbert wrote to magnet a in which he made a careful study of electricity and, magnetism distinguishing. The lodestone, effect from static electricity produced. By rubbing amber he. Coined the new Latin word electric as' of amber, or, like, amber from, electron-electron, the, Greek word for Amber. To refer, to the property of attracting, small objects after being rubbed this. Association, gave rise to the English words electric. And, electricity. Which. Made their first appearance in print in Thomas Browne pseudo Doc Co epidemic, of 1646. Further work was conducted in the 17th, and early 18th centuries. By Otto von Guericke II Robert Boyle Stephen gray and CF du Fay. Later, in the 18th century Benjamin, Franklin conducted, extensive research, in electricity selling, his possessions, to fund his work in. June 1750. - he is reputed to have attached a metal key to the bottom of a dampen kite string and flown the kite in a storm threatened, sky a succession. Of sparks jumping from the key to the back of his hand showed that lightning was indeed electrical, in nature he. Also explained, the apparently paradoxical. Behavior of the Leyden jar is a device for storing large amounts of electrical, charge in terms of electricity consisting, of both positive and negative charges, in. 1791. Luigi, Galvani published, his discovery of bio electro magnetics demonstrating. That electricity was the medium by which neurons passed signals, to the muscles. Alessandro. Voltas battery or voltaic, pile of 1800, made from alternating, layers of zinc and copper provided, scientists, with a more reliable source of electrical, energy than the electrostatic. Machines previously, used the. Recognition, of electromagnetism. The unity of electric, and magnetic phenomena. Is due to Hans Christian ørsted and Andre Murray ampere in 1819.
To 1820. Michael. Faraday invented, the electric motor in 1821, and Georg, ohm mathematically. Analyzed the electrical, circuit in 1827. Electricity. And magnetism, and light were, definitively, linked by James Clerk Maxwell in, particular in his on physical. Lines of force in. 1861. And 1862, while the early 19th century had seen rapid progress in electrical, science the late 19th century would see the greatest progress in Electrical Engineering through. Such people as Alexander, Graham Bell Otto bloody, thomas edison galileo, ferraris, oliver heaviside Enya's jedlica William Thompson 1st Baron Kelvin Charles alderman Parsons Werner von Siemens Joseph, Swan Reginald, Fessenden, Nikola Tesla and George Westinghouse electricity. Turned from a scientific, curiosity into, an essential, tool for modern life in. 1887. Heinrich, Hertz discovered, that electrodes, illuminated, with ultraviolet, light create electric sparks more easily in. 1905. Albert Einstein, published a paper that explained experimental, data from the photoelectric, effect as being the result of light energy being carried in discrete quantized packets, energizing, electrons, this. Discovery, led to the quantum revolution, Einstein. Was awarded the Nobel Prize in Physics in 1921, for, his, discovery, of the law of the photoelectric effect. The photoelectric. Effect is also employed in photo cells such as can be found in solar panels and this is frequently used to make electricity commercially. The. First solid-state, device was the cat's, whisker detector first. Used in the 1900s. In radio receivers, a whisker, like wire is placed lightly, in contact, with a solid crystal such as a germanium, crystal to detect a radio signal by the contact junction effect in. A solid-state, component, the current is confined to solid elements and compounds engineered. Specifically, to switch and amplify it current. Flow can be understood in two forms as negatively, charged electrons, and as positively charged electron, deficiencies, called holes these. Charges, and holes are understood in terms of quantum physics the building, material, is most often a crystalline, semiconductor the, solid-state device came into its own with the invention of the transistor in, 1947. Common. Solid-state, devices include, transistors, microprocessor. Chips and RAM a specialized. Type of RAM called flash Ram is used in USB flash drives and more recently solid-state, drives to replace mechanically, rotating, magnetic disk hard disk drives solid-state. Devices. Became, prevalent in the 1950s. In the 1960s. During the transition, from vacuum tubes to semiconductor, diodes transistors, integrated. Circuit IC and the light emitting diode led. Topic. Concepts. Topic. Electric. Charge. The. Presence of charge gives rise to an electrostatic, force, charges, exert a force on each other an effect that was known though not understood, in antiquity, a lightweight. Ball suspended from a string can be charged by touching it with a glass rod that has itself been charged by rubbing with a cloth if. A similar ball is charged by the same glass rod it is found to repel the first the charge acts to force the two balls apart two. Balls that are charged with a rubbed amber rod also repel each other however. If one ball is charged by the glass rod and the other by an amber rod the two balls are found to attract each other, these. Phenomena, were investigated, in the late 18th century by charles-augustin, de, Coulomb who deduced that charge manifests, itself in two opposing forms this.
Discovery, Led to the well-known axiom, like charged objects repel and opposite charged objects, attract the force acts on the charged particles, themselves hence charge has a tendency, to spread itself as evenly as possible over a conducting, surface the. Magnitude, of the electromagnetic. Force whether attractive, or repulsive is given by Coulomb's law which relates the force to the product of the charges and has an inverse-square relation, to the distance between them the. Electromagnetic. Force is very strong second. Only in strength to the strong interaction, but unlike that force it operates over all distances, in, comparison. With the much weaker gravitational, force, the electromagnetic, force pushing two electrons, apart is 1042, times that of the gravitational, attraction pulling, them together study, has shown that the origin of charges, from certain types of subatomic particles, which have the property of electric, charge, electric. Charge gives rise to and interacts with the electromagnetic. Force one of the four fundamental forces of nature the. Most familiar carriers, of electrical, charge of the electron and proton. Experiment. Has shown charge to be a conserved, quantity that is the net charge within an electrically isolated, system, will always remain constant regardless of any changes taking place within that system within. The system charge may be transferred, between bodies, either by direct contact or by passing along a conducting, material such, as a wire the. Informal, term static electricity refers, to the net presence or imbalance, of charge on a body usually caused when dissimilar materials, are rubbed together transferring. Charge from one to the other the. Charge on electrons, and protons is, opposite in sign hence, an amount of charge may be expressed, as being either neg or positive by. Convention, the charge carried by electrons is, deemed negative and that by protons, positive a custom that originated, with the work of Benjamin Franklin the amount. Of charge is usually given the symbol Q and expressed in coulombs each electron, carries the same charge of approximately, minus one point six zero to two times ten minus 19 coulomb the. Proton has a charge that is equal and opposite and thus plus one point six zero to two times ten minus 19 Coulomb charge is. Possessed not just by matter but also by antimatter each antiparticle. Bearing an equal and opposite charge to its corresponding particle, charge can be measured by a number of means and early instrument, being the goldleaf electroscope, which although still in use for classroom demonstrations, has been superseded, by the electronic, electrometer. Topic. Electric. Current the. Movement. Of electric charge is known as an electric current the intensity, of which is usually measured in amperes current can. Consist of any moving charged particles most commonly these are electrons, but any charge in motion constitutes, a current, electric. Current can flow through some things electrical, conductors, but will not flow through an electrical, insulator by historical, convention, a positive current is defined as having the same direction of flow as any positive, charge it contains or to flow from the most positive part of a circuit to the most negative part, current. Defined in this manner is, called conventional current the, motion of negatively, charged electrons, around an electric circuit one of the most familiar forms of current is the steam positive, in the opposite direction to that of the electrons, however. Depending. On the conditions, an electric, current can consist of a flow of charged particles in either direction or even in both directions at once the. Positive to negative convention. Is widely used to simplify this situation. The. Process, by which electric, current passes through a material is termed electrical, conduction and its nature varies, with that of the charged particles and the material, through which they are traveling. Examples. Of electric currents include metallic, conduction, where electrons, flow through a conductor, such as metal and electrolysis, where ions charged, atoms flow through liquids or through plasmas such as electrical, sparks while. The particles, themselves can, move quite slowly sometimes, with an average drift velocity, only fractions, of a millimeter per second the electric field that drives them itself propagates, at close to the speed of light enabling, electrical. Signals to pass rapidly along wise current, causes several observable, effects which historically, were the means of recognizing, its presence that.
Water Could be decomposed by the current from a voltaic pile was discovered, by Nicholson, and Carlisle in 1800, a process now known as electrolysis, their. Work was greatly expanded upon by Michael Faraday in 1833. Current. Through a resistance, causes localized, heating and effect James Prescott Joule studied, mathematically, in 1840. One. Of the most important, discoveries relating, to current was made accidentally, by Hans Christian ørsted in 1820, went while preparing a lecture he witnessed the current in a wire disturbing. The needle of a magnetic compass he. Had discovered electromagnetism. A fundamental, interaction, between electricity, and magnetics, the. Level of electromagnetic, emissions generated. Electric, arcing is high enough to produce electromagnetic. Interference, which can be detrimental to the workings of adjacent, equipment in engineering, or household applications, current is often described as being either direct current DC or alternating, current AC these. Terms refer to how the current varies in time direct. Current is produced by example, from a battery and required by most electronic, devices is a unidirectional. Flow from the positive part of a circuit to the negative if, as is most common this flow is carried by electrons they, will be traveling in the opposite direction. Alternating. Current is any current that reverses, direction, repeatedly, almost always this takes the form of a sine wave, alternating. Current thus, pulses back and forth within a conductor without the charge moving any net distance over time the. Time averaged value of an alternating current is zero but it delivers energy in first one direction, and then the reverse. Alternating. Current is affected by electrical, properties that are not observed under steady state direct, current such as inductance and capacitance, these. Properties, however can become important, when circuitry, is subjected, to transients, such as when first energized. Topic. Electric. Field. The. Concept, of the electric field was introduced by Michael Faraday an electric. Field is created by a charged body in the space that surrounds it and results, in a force exerted on any other charges placed within the field the. Electric field acts between two charges in a similar manner to the way that the gravitational, field acts between two masses and like it extends, towards infinity and shows an inverse-square relationship. With distance, however. There is an important, difference gravity. Always acts in attraction, drawing two masses together while, the electric field can result in either attraction, or repulsion, since. Large bodies such as planets generally carry no net charge the electric field at a distance is usually zero thus. Gravity, is the dominant force at distance in the universe despite, being much weaker an, electric. Field generally, varies in space and its strength at any one point is defined as the force per unit charge that would be felt by a stationary, negligible, charge if placed at that point the.
Conceptual, Charge termed a test charge must be vanishingly, small to prevent its own electric, field disturbing, the main field and must also be stationary to prevent the effect of magnetic fields, as the. Electric field is defined in terms of force and force is a vector so it follows that an electric field is also a vector having both magnitude and direction. Specifically. It is a vector field the study of electric fields created by stationary, charges is called electrostatics. The. Field may be visualized, by a set of imaginary, lines whose direction, at any point is the same as that of the field this. Concept, was introduced, by faraday whose term lines of force still sometimes sees use the. Field lines are the paths that a point positive charge would seek to make as it was forced to move within the field they are however an imaginary, concept with no physical existence and the field permeates all the intervening space between the lines field. Lines emanating from stationary, charges, have several key properties first that they originate, at positive charges and terminate at negative charges second, that they must enter any good conductor, at right angles and third that they may never cross more closing on themselves, a hollow conducting, body carries all its charge on its outer surface the field. Is therefore zero at all places inside the body this, is the operating, principle of the Faraday cage a conducting, metal shell which isolates, its interior from outside electrical, effects, the. Principles, of elector statics are important when designing items, of high voltage equipment there. Is a finite limit to the electric field strength that may be withstood by any medium, beyond. This point electrical, breakdown occurs, in an electric arc causes, flashover between, the charged parts air. For example tends to arc across small gaps at electric field strengths which exceed 30 kilo volts per centimeter over, larger. Gaps its breakdown strength is weaker perhaps 1 kilo volt per centimeter, the. Most visible natural, occurrence of this is lightning caused when charge becomes separated, in the clouds by rising columns of air and raises the electric field in the air to greater than it can withstand the. Voltage of a large lightning, cloud may be as high as 100 mega volts and have discharge energies as great as 250. Kilowatt hours the field strength is greatly affected by nearby conducting, objects and it is particularly intense when it is forced to curve around sharply, pointed objects this. Principle, is exploited, in the Lightning conductor the sharp spike of which acts to encourage, the Lightning stroke to develop there rather than to the building it serves to protect. Topic. Electric. Potential. The. Concept, of electric potential is closely linked to that of the electric field a small. Charge placed within an electric field experiences. A force and to have brought that charge to that point against the force requires work the. Electric, potential at any point is defined as the energy required to bring a unit test charge from an infinite distance slowly to that point it. Is usually measured in volts and one volt is the potential, for which one Joule of work must be expended to bring a charge of one Coulomb from infinity, this. Definition, of potential while formal has little practical application, and the more useful concept, is that of electric potential difference and is the energy required to move a unit charge, between two specified, points an electric. Field has the special property that it is conservative which means that the path taken by the test charge is irrelevant all paths between two specified, points expend the same energy and thus a unique value for potential, difference may be stated the. Volt is so strongly identified, as the unit of choice for measurement and description, of electric potential difference that the term voltage sees greater everyday usage, for. Practical purposes it is useful to define a common reference point to which potentials, may be expressed, and compared while. This could be at infinity a much more useful reference, is the earth itself which is assumed to be at the same potential everywhere this. Reference point naturally, takes the name earth or ground earth. Is assumed to be an infinite source of equal amounts of positive and negative charge and is therefore electrically, uncharged, a nun, chargeable, electric, potential is a scalar quantity that, is it has only magnitude and not Direction, it. May be viewed as analogous to height just as a released object will fall through a difference in Heights caused by a gravitational field, so a charge will fall across the voltage caused by an electric field as relief. Maps show contour, lines marking points of equal height a set of lines marking points of equal potential known as equip potentials, may be drawn around an electro statically charged object the.
Equip Attentions, cross all lines of force at right angles, they, must also lie parallel to a conductors surface otherwise this would produce a force that will move the charge carriers, to even the potential of the surface, the. Electric, field was formally defined as the force exerted per unit charge but the concept of potential, allows for a more useful in equivalent, definition, the electric field is the local gradient of the electric potential. Usually. Expressed in volts per meter the vector direction, of the field is the line of greatest slope of potential, and where the equip attentions like closest together. Topic. Electromagnets. Boston's. Discovery, in 1821, that a magnetic, field existed, around all sides of a wire carrying an electric current indicated, that there was a direct relationship between electricity, and magnetism, moreover. The interaction, seemed different from gravitational, and electrostatic, forces, the two forces of nature then known the. Force on the compass needle did, not direct it to or away from the current carrying wire but, acted at right angles to it or, stood slightly obscure words were that the electric, conflict acts in a revolving manner the. Force also depended, on the direction of the current for if the flow was reversed then the force did too Oster did not fully understand, his discovery, but he observed the effect was reciprocal, a current exerts a force on a magnet and a magnetic field exerts a force on a current the. Phenomenon, was further investigated. By ampair who discovered that two parallel, current-carrying wires, exerted, a force upon, each other to Weis conducting, currents in the same direction are, attracted, to each other while wise containing, currents in opposite directions are, forced apart the. Interaction, is mediated, by the magnetic field each current produces and forms the basis for the International, definition, of the ampere, this. Relationship, between magnetic, fields and currents is extremely, important, for it led to Michael Faraday's invention, of the electric motor in 1821. Faraday's. Homopolar, motor consisted. Of a permanent magnet sitting in a pool of mercury a current.
Was Allowed through a wire suspended from a pivot above the magnet and dipped into the mercury the. Magnet exerted a tangential, force on the wire making it circle around the magnet for as long as the current was maintained, experimentation. By Faraday in 1831, revealed, that a wire moving perpendicular, to a magnetic, field developed, a potential, difference between its ends further. Analysis, of this process, known as electromagnetic induction, enabled. Him to state the principle now known as Faraday's, law of induction that, the potential difference induced, in a closed circuit is proportional, to the rate of change of magnetic flux, through the loop. Exploitation. Of this discovery enabled, him to invent the first electrical, generator in 1831. In which he converted the mechanical, energy of a rotating copper, disc to electrical, energy Faraday's. Disk was inefficient and of no use as a practical generator, but it showed the possibility of generating electric, power using, magnetism a possibility, that would be taken up by those that followed on from his work. Topic. Electrochemistry. The. Ability of chemical, reactions, to produce electricity, and conversely, the ability of electricity, to drive chemical, reactions, has a wide array of uses. Electrochemistry. Has always been an important, part of electricity from, the initial invention, of the voltaic pile, electrochemical. Cells have evolved into the many different types of batteries electroplating. And electrolysis, cells. Aluminium. Is produced in vast quantities this way and many portable, devices are electrically, powered using rechargeable cells. Topic. Electric. Circuits. An electric. Circuit is an interconnection, of electric components, such that electric charge is made to flow along a closed path a circuit usually, to perform some useful task the. Components, in an electric circuit can take many forms which can include elements, such as resistors, capacitors switches. Transformers. In electronics. Electronic. Circuits contain active components, usually semiconductors. And typically exhibit nonlinear, behavior requiring, complex, analysis, the. Simplest electric components, are those that are termed passive and linear while they may temporarily store energy they contain no sources of it and exhibit linear responses, to stimuli the resistor is perhaps the simplest of passive circuit elements as its name suggests it resists the current through it dissipating, its energy as heat the. Resistance, is a consequence, of the motion of charge through a conductor, in metals for example resistance. Is primarily, due to collisions, between electrons and, ions Ohm's. Law is a basic law of circuit theory stating, that the current passing through a resistance, is directly proportional. To the potential difference across it the. Resistance of most materials, is relatively constant over a range of temperatures, and currents materials, under these conditions, are known as ohmic the. Ohm the unit of resistance was named in honor of Georg ohm and is symbolized by the Greek letter Omega one, ohm is the resistance that will produce a potential, difference of one volt in response to a current of 1 amp the capacitor, is a development, of the Leyden jar and is a device that can store charge and thereby storing, electrical, energy in the resulting field it. Consists, of two conducting, plates separated, by a thin insulating, dielectric, layer in practice, thin metal foils are coiled together increasing. The surface area per unit volume and therefore the capacitance, the. Unit of capacitance, is the farad named after Michael Faraday, and given the symbol F 1 farad is the capacitance, that develops, a potential difference of one volt when it stores a charge of one Coulomb a capacitor. Connected to a voltage supply initially, causes a current as it accumulates charge, this current will however decay, in time as the capacitor, fills eventually, falling to zero a capacitor. Will therefore not permit a steady state current but instead blocks it the inductor is a conductor, usually, a coil of wire that stores energy in a magnetic field in response to the current through it when. The current changes the magnetic field does - inducing, a voltage between the ends of the conductor the. Induced voltage is proportional to the time rate of change of the current the. Constant, of proportionality is. Termed the inductance. Unit of inductance is, the Henry named after Joseph Henry, a contemporary, of Faraday 1. Henry is the inductance that will induce a potential, difference of one volt if the current through it changes at a rate of 1 ampere per second the. Inductors, behavior is in some regards converse, to that of the capacitor, it will freely allow an unchanging, current but opposes, a rapidly changing one.
Topic. Electric. Power. Electric. Power is the rate at which electric, energy is transferred, by an electric circuit the. SI unit of power is the watt one Joule per second. Electric. Power like mechanical, power is the rate of doing work measured, in watts and represented, by the letter P the term wattage is used colloquially to, mean electric, power in watts the. Electric, power in watts produced, by an electric current are consisting, of a charge of Q coulombs every T seconds passing through an electric potential voltage difference, of V P. Equals. Work. Done per unit time. Equals. Q. V. T. Equals. I. V. Display. Style P equals text work done per unit time equals, phrack QV, t equals, I V where. Q. Is electric, charge in coulombs, T. Is time in seconds I use. Electric current in amperes, V. Is electric, potential, or voltage in volts electricity. Generation is often done with electric, generators, but can also be supplied by chemical, sources such as electric batteries or by other means from a wide variety of sources of energy, electric. Power is generally supplied to businesses and homes by the electric, power industry. Electricity. Is usually, sold by the kilowatt hour three point six mega joules which is the product of power in kilowatts multiplied. By running time in hours, electric. Utilities measure power using, electricity meters, which keep a running total of the electric energy delivered, to a customer, unlike. Fossil fuels electricity. Is a low entropy form of energy and can be converted into motion or many other forms of energy with high efficiency. Topic. Electronics. Electronics. Deals with electrical, circuits that involve active electrical, components, such as vacuum tubes transistors diodes, optoelectronics. Sensors, and integrated, circuits and associated. Passive interconnection technologies. The. Nonlinear, behavior of active components, and their ability to control electron, flows makes amplification. Of weak signals possible, in electronics, is widely used in information processing, telecommunications. And signal, processing the. Ability of electronic, devices to act as switches makes digital information, processing, possible. Interconnection. Technologies such, as circuit boards electronics, packaging technology, and other varied forms of communication, infrastructure, complete, circuit functionality, and transform, the mix components, into a regular working system, today. Most electronic, devices use semiconductor. Components to perform electronic, control the. Study of semiconductor. Devices and, related technology, is considered a branch of solid-state, physics, whereas the design and construction of electronic, circuits to solve practical problems come, under Electronics, Engineering.
Topic. Electromagnetic. Wave. Faraday's. And amp ere's work showed that I'm varying, magnetic field acted, as a source of an electric field and a time varying electric field, was a source of a magnetic field thus. When a the field is changing in time then a field of the other is necessarily, induced, such. A phenomenon, has the properties of a wave and is naturally, referred to as an electromagnetic. Wave electromagnetic. Waves, were analyzed theoretically, by James Clerk Maxwell in, 1864. Maxwell. Developed, a set of equations, that could unambiguously, describe, the interrelationship. Between electric. Field magnetic, field electric, charge and electric, current he. Could moreover, prove that such a wave would necessarily travel at the speed of light and the slide itself was a form of electromagnetic, radiation. Maxwell's. Laws which, unify light fields, and charge a one of the great milestones, of theoretical, physics thus the work of many researchers enabled, the use of electronics, to convert signals into high frequency, oscillating currents, and via suitably shaped conductors, electricity. Permits the transmission, and reception of these signals via radio waves over very long distances. Topic. Production. And users. Topic. Generation. And transmission. In, the 6th century BC, the Greek philosopher, Thales of Miletus experimented. With amber odds and these experiments, were the first studies into the production of electrical, energy while. This method now known as the triboelectric effect can lift light objects, and generate sparks it is extremely, inefficient it. Was not until the invention of the voltaic pile, in the 18th century that a viable source of electricity became available the voltaic. Pile and it's modern descendant, the electrical, battery store, energy chemically, and make it available on demand in the form of electrical, energy the. Battery is a versatile, and very common power source which is ideally suited to many applications, but it's energy storage is finite and once discharged, it must be disposed of or recharged, for. Large electrical, demands electrical, energy must be generated, and transmitted, continuously over, conductive, transmission, lines. Electrical. Power is usually generated by electromechanical, generators. Driven by steam produced from fossil fuel, combustion or the heat released from nuclear reactions or from other sources such as kinetic, energy extracted from wind or flowing water the modern, steam turbine, invented, by Sir Charles Parsons in 1884. Today generates, about 80 percent of the electric power in the world using a variety of heat sources, such. Generators bear no resemblance to Faraday's, homopolar, disc generator of 1831, but they still rely on his electromagnetic. Principle, that a conductor linking, a changing magnetic field, induces, a potential, difference across a TENS the. Invention, in the late 19th, century of the transformer, meant that electrical, power could be transmitted, more efficiently at a higher voltage but lower current, efficient.
Electrical, Transmission meant, in turn that electricity, could be generated, at centralized, power stations, where it benefited from economies, of scale and then be dispatched relatively, long distances to where it was needed, since. Electrical, energy cannot easily be stored in quantities, large enough to meet demands on a national, scale at all times exactly as much must be produced as is required this. Requires electricity, utilities. To make careful, predictions, of their electrical, loads and maintain, constant coordination. With their power stations, a certain. Amount of generation must always be held in reserve to cushion an electrical, grid against inevitable, disturbances, and losses. Demand. For electricity grows, with great rapidity as a nation modernizes in its economy develops, the. United, States showed a 12%, increase in demand during each year of the first three decades of the 20th century a rate of growth that is now being experienced, by emerging, economies such as those of India or China, historically. The growth rate for electricity, demand has outstripped that for other forms of energy environmental. Concerns with electricity generation, have led to an increased focus on generation, from renewable, sources in particular from wind and hydro power while. Debate can be expected, to continue over the environmental, impact of different means of electricity, production its final form is relatively clean. Topic. Applications. Electricity. Is a very convenient way to transfer, energy and it has been adapted to a huge and growing number, of uses the. Invention, of a practical, incandescent light, bulb in the 1870s. Led to lighting becoming one of the first publicly available applications. Of electrical, power, although. Electrification, brought, with it its own dangers replacing, the naked flames of gas lighting greatly, reduced fire hazards within homes and factories, public. Utilities, were set up in many cities targeting, the burgeoning market for electrical lighting in. The late 20th century and in modern times the trend has started to flow in the direction of deregulation, in the electrical, power sector, the resistive, Joule heating effect employed, in filament lightbulbs also sees more direct use in electric heating while. This is versatile, and controllable, it can be seen as wasteful since most electrical, generation has already required the production of heat at a power station a number. Of countries such as Denmark have issued legislation, restricting or banning the use of resistive, electric heating in new buildings. Electricity. Is however still a highly practical energy source for heating and refrigeration with. Air-conditioning heat, pumps representing, a growing sector for electricity, demand for heating and cooling the effects of which electricity, utilities, are increasingly, obliged to accommodate, electricity. Is used within telecommunications. And indeed the electrical, Telegraph demonstrated. Commercially, in 1837. By Cooke and Wheatstone was, one of its earliest applications. With. The construction of first intercontinental. And then transatlantic, Telegraph. Systems in the 1860s. Electricity. Had enabled communications. In minutes across the globe, optical. Fiber and satellite communication. Have taken a share of the market for communication, systems, but electricity can be expected, to remain an essential part of the process, the. Effects of electromagnetism. Are most visibly employed in the electric motor which provides a clean and efficient means of motivepower, a stationary. Motor such as a winch is easily provided with a supply of power but a motor that moves with its application such, as an electric vehicle is obliged to either carry along a power source such as a battery or to collect current from a sliding contact such as a pantograph. Electrically. Powered vehicles, are used in public transportation such, as electric buses and trains and an increasing, number of battery-powered electric, cars in private ownership. Electronic. Devices make use of the transistor, perhaps one of the most important, inventions of the 20th century, and the fundamental, building block of all modern circuitry.
A Modern, integrated circuit, may contain several billion miniaturized, transistors. In a region only a few centimeter square. Topic. Electricity. In the natural, world. Topic. Physiological. Effect. A voltage. Applied to a human body causes, an electric current through the tissues and although the relationship is nonlinear, the greater the voltage the greater the current the. Threshold, for perception varies, with the supply frequency and, with the path of the current but is about 0.1. Milli amperes to 1 milliampere, for mains frequency electricity, though a current as low as a micro amp can be detected as an electro vibration, effect under certain conditions, if. The current is sufficiently, high it will cause muscle contraction, fibrillations, of the heart and tissue burns the. Lack of any visible sign that a conductor is electrified, makes electricity, a particular hazard, the. Pain caused by an electric shock can be intense bleeding electricity, at times to be employed as a method of torture death. Caused by an electric, shock is referred to as electrocution. Electrocution. Is still the means of judicial execution, in some jurisdictions, though its use has become rarer, in recent times. Topic. Electrical. Phenomena, in nature. Electricity. Is not a human invention and may be observed in several forms, in nature a prominent manifestation. Of witches lightning many. Interactions, familiar at the macroscopic level such, as touch friction, or chemical bonding are due to interactions, between electric, fields on the atomic scale the. Earth's magnetic, field is thought to arise from a natural dynamo of circulating, currents in the planets core certain. Crystals such as quartz or even sugar generate, a potential, difference across their faces when subjected to external pressure this. Phenomenon, is known as piezoelectricity from, the Greek peers around peers are an meaning to press and was discovered in 1880, by Pierre and Jacques Curie the. Effect is reciprocal, and when a piezoelectric, material is subjected to an electric field a small change in physical dimensions, takes place section, bioelectric, genesis in microbial, life is a prominent phenomenon, in soils in sediment ecology, resulting, from anaerobic respiration, the. Microbial, fuel cell mimics this ubiquitous natural, phenomenon.
Some. Organisms, such as sharks are able to detect and respond to changes in electric, fields and ability, known as electroreception. While others termed electrogenic. Are able to generate voltages. Themselves, to serve as a predatory or defensive, weapon the. Order Jim Noda forms of which the best-known example, is the electric eel detect or stun their prey by a high voltage is generated from, modified muscle cells called electrocytes, all. Animals, transmit information along their cell membranes with voltage pulses called action potentials, whose functions, include communication by the nervous system between neurons and muscles an electric. Shock stimulates, this system and causes, muscles to contract, action. Potentials are also responsible, for coordinating activities, in certain plants. Topic. Cultural. Perception. In, 1850. William Gladstone asked the scientist, Michael Faraday why, electricity, was valuable, Faraday. Answered one day sir, you may tax it in the 19th and early 20th century, electricity, was not part of the everyday life of many people even in the industrialized, Western world the. Popular culture of the time accordingly, often depicted it as a mysterious, quasi magical, force that can slay the living revive the dead or otherwise bend the laws of nature this. Attitude began with the 1771. Experiments. Of Luigi Galvani in which the legs of dead frogs were shown to twitch on application, of animal electricity. Revitalization. Or, resuscitation. Of apparently, dead or drowned persons, was reported, in the medical literature shortly. After Galvani's, work these. Results were known to Mary Shelley when she authored Frankenstein, 1819. Although she does not name the method of revitalization. Of the monster the. Revitalization. Of monsters with electricity, later, became a stock theme in horror films as the. Public familiarity, with electricity is the lifeblood of the Second Industrial Revolution, group, its wielders were more often cast in a positive light such as the workers who finger. Death at their gloves end as they peace and repeats the living wires, in. Rudyard, Kipling's 1907. Poem sons of martha electrically. Powered vehicles, of every sort featured large in adventure stories such as those of jules verne in the Tom Swift books the. Masters of electricity where the fictional or real including. Scientists, such as Thomas Edison Charles, Steinmetz, or Nikola Tesla were, popularly conceived, of as having wizard-like powers, with electricity ceasing, to be a novelty and becoming a necessity of, everyday life in the latter half of the 20th century it required particular attention, by popular, culture only when it stops flowing an event that usually signals disaster, the. People who keep it flowing such as the nameless hero of Jimmy Webb song Wichita. Lineman. 1968. Are still often cast as heroic wizard-like figures. Topic. See also. Ampère's. Circuital law connects, the direction, of an electric current and its associated, magnetic, currents. Electric. Potential energy the potential energy of a system of charges. Electricity. Market the sale of electrical, energy. Hydraulic. Analogy an analogy, between the flow of water and electric current, equals. Equals nodes.
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