wiktionary ElectromagneticElectromagnetic may refer to Electromagnetism Electromagnetic field ElectromagneticforceElectromagnetic radiation Electromagnetic induction Electromagnetic spectrum Electromagnetic therapy alternative medicine , use of electromagnetism in alternative medicine Electromagnetic weapon , a type of Directed energy weapon Electromagnetic propulsion Electromagnetic pulse Electromagnetic levitation Electromagnetic shielding disambig ... more details
Orphan date February 2009 Electromagnetic buoyancy EMB is a force that opposes Lorentz force EMW during electromagnetic phoresis of small particles or droplets in an aqueous medium. Though this force is still being researched, it has been clearly observed in experimental procedures. Category Electromagnetism electromagnetism stub ... more details
In telecommunication , the term electromagnetic environment EME has the following meanings For a telecommunications system , the spatial distribution of electromagnetic field s surrounding a given site. The electromagnetic environment may be expressed in terms of the spatial and temporal distribution of electric field strength volt s per metre , irradiance watt s per square metre , or energy density joule s per cubic metre . The resulting product of the Power physics power and time distribution, in various frequency ranges, of the radiated or conducted electromagnetic Emission electromagnetic radiation emission levels that may be encountered by a military force, system, or platform when performing its assigned mission in its intended operational environment. It is the sum of electromagnetic interference electromagnetic pulse hazards of electromagnetic radiation to personnel, ordnance, and volatile materials and natural phenomena effects of lightning and p static. Source FS1037C MS188 DODDIC Category Electromagnetic radiation Category Telecommunications telecomm stub pl rodowisko elektromagnetyczne ru ... more details
electromagnetism cTopic Electrodynamics An electromagnetic pump is a pump that moves liquid metal or any electrically conductive liquid using electromagnetism . A magnetic field is set at right angles to the direction the liquid moves in, and a current is passed through it. This causes an electromagneticforce that moves the liquid. Applications include pumping liquid metal through a cooling system. See also Electromagnetic flow meter Molten salt References references Bibliography R. S. Baker Handbook of Electromagnetic pump technology External links http lecturedemo.ph.unimelb.edu.au Electricity Magnetism Forces fields from currents Ea 5 The Electromagnetic Pump demo http www.comsol.com papers 9352 http www.carli ea.com eng c3b.htm Category Pumps electromagnetism stub ro Pomp electromagnetic ... more details
Electromagnetic flux may refer to one of the following Flux or flux density of electromagnetic radiation Electric flux and magnetic flux . disambig ... more details
. The way in which charges and currents interact with the electromagnetic field is described by Maxwell s equations and the Lorentz force law . From a Classical physics classical perspective, the electromagnetic ... Force Law Lorentz force law . This discussion ignores the radiation reaction force . Electromagnetic ... electric and magnetic fields fields act upon particles Lorentz forceforce due to electromagnetic field .... The Lorentz force law governs the interaction of the electromagnetic field with charged matter ...Merge from Flux density discuss Talk Electromagnetic field Merger proposal Flux density date October 2011 Electromagnetism cTopic Classical electromagnetism Electrodynamics An electromagnetic field also ... charged objects . It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetism electromagnetic interaction . It is one of the four fundamental force s of nature the others are gravitation , the weak ... of individual Subatomic particle particle s. Citation needed date May 2011 Structure of the electromagnetic field The electromagnetic field may be viewed in two distinct ways a continuous structure or a discrete ..., energy is viewed as being transferred continuously through the electromagnetic field between any ... at high frequencies see ultraviolet catastrophe . Discrete structure The electromagnetic field may be thought of in a more coarse way. Experiments reveal that in some circumstances electromagnetic energy ... effect the emission of electrons from metallic surfaces subjected to electromagnetic radiation ... electrons. This quantum picture of the electromagnetic field which treats it as analogous to harmonic ... theory describing the interaction of electromagnetic radiation with charged matter. It also gives ... is modelled using quantum mechanics rather than Quantum field theory . Dynamics of the electromagnetic ... thought of as two parts of a greater whole the electromagnetic field. Once this electromagnetic ... more details
Refimprove All references are from a single source commercial site ogura clutch.com date June 2011 Electromagnetic ... brakes became known as electromagnetic, referring to their actuation method. Since the brakes started ... by mechanical means. Applications On tram s and train s, an Electromagnetism electromagnetic brake is a track brake where the braking element is pressed by magnetic force to the Rail tracks rail , i.e. the braking is by friction , not the magnetic effect directly. Types of Electromagnetic Brakes Single face electromagnetic brakes Image A 3 electromagnetic brake1.gif thumb 150px right A 3 Electromagentic brake Main Friction plate electromagnetic couplings A friction plate brake uses a single plate friction surface to engage the input and output members of the clutch. Single face electromagnetic brakes make up approximately 80 of all of the power applied brake applications. Electromagnetic Power Off Brake Image Electromagnetic Power Off Brake.gif thumb 175px left Electormagnetic Power .... This frictional clamping force is transferred to the hub, which is mounted to a shaft. Permanent Magnet Type A permanent magnet holding brake looks very similar to a standard power applied electromagnetic ... in diameter or would need stacked friction disks to increase the torque. Electromagnetic Particle Brake Image Electromagnetic Particle Brake.gif thumb 175px right Magnetic Particle Brake Introduction ... start to bind together, a resistant force is created on the rotor, slowing, and eventually stopping ... of minimum drag associated with them. Electromagnetic Hysteresis Power Brake Image Electromagnetic ... force is transmitted between either member. Therefore, the only torque seen between the input and the output is bearing drag. Multiple Disk Brakes Image Multiple disk electromagnetic brake1.gif thumb 175px right Electromagnetic Multiple Disk Brake Introduction Multiple disk brakes are used ... Eddy current brake Brake run Electromagnetic clutch References reflist DEFAULTSORT Electromagnetic ... more details
refimprove date March 2010 Image Electromagnetic shielding inside mobile phone.jpg thumb Electromagnetic shielding cages inside a disassembled mobile phone . Electromagnetic shielding is the process of reducing the electromagnetic field in a space by blocking the field with barriers made of electrical ... through which the cable runs. Electromagnetic shielding that blocks radio frequency electromagnetic ... of Radio frequency radio waves , electromagnetic fields and electrostatic field s, though not static ... of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic field. Materials used Typical materials used for electromagnetic shielding include sheet metal ... layers One example is a shielded cable , which has electromagnetic shielding in the form of a wire ... electromagnetic and electrostatic fields. The door of a microwave oven has a screen built into the window ... needed date August 2011 NATO specifies electromagnetic shielding for computers and keyboards to prevent ... http lasecwww.epfl.ch keyboard title Compromising Electromagnetic Emanations of Wired and Wireless Keyboards ..., FM or TV broadcast facilities. How electromagnetic shielding works Electromagnetic radiation consists ... force s on the electric charge charge carriers i.e., electron s within the conductor. As soon as an electric ... unless the conductor is moving relative to the magnetic field. The result is that electromagnetic ... in the shield force current to flow around them, so that fields passing through the holes do not excite opposing electromagnetic fields. These effects reduce the field reflecting capability of the shield. In the case of high frequency electromagnetic radiation, the above mentioned adjustments take ... by the skin unless it is extremely thin , so in this case there is no electromagnetic field ... Ed. Section 5.12 ref See also Electromagnetic interference Electromagnetic radiation and health Radiation ... www.learnemc.com tutorials Shielding02 Practical Shielding.html Practical Electromagnetic Shielding ... more details
force to operate the clutch. It is a type of semi automatic transmission . Electromagnetic clutches ...unref date August 2011 Electromagnetic clutches operate electrically, but transmit torque mechanically ... known as electromagnetic versus electro mechanical, referring more about their actuation method versus .... Single face clutches make up approximately 90 of all electromagnetic clutch sales. The electromagnetic .... It has fast, smooth operation. However, because energy dissipates as heat in the electromagnetic ... plate clutch Main Friction plate electromagnetic couplings A friction plate clutch uses a single plate friction surface to engage the input and output members of the clutch. How it works Image B 1 electromagnetic ... and a frictional force is generated at contact. Within a relatively short time, the load is accelerated ... automation. Automobiles When the electromagnetic clutch is used in automobiles , there may be a clutch ... to individual wheels or axles. A smaller electromagnetic clutch connects the air conditioning compressor ... Electromagnetic clutches have been used on diesel locomotive s, e.g. by Hohenzollern Locomotive Works . Other types of electromagnetic clutches Multiple disk clutches Image Multiple Disk Clutch.gif .... Electromagnetic tooth clutches Image Electromagnetic Tooth Clutch.gif thumb 200px right Electromagnetic tooth clutch Introduction Of all the electromagnetic clutches, the tooth clutches provide the greatest ... otherwise damage to the clutch teeth would occur when trying to engage the clutch. How it works Electromagnetic ... from input to output. Electromagnetic particle clutches Main magnetic particle clutch Image Electromagnetic Particle Clutch.gif thumb 200px left Electromagnetic particle clutch Introduction ... range of any electromagnetic product. Most applications involving powered hysteresis units are in test ... current is removed from the clutch, the armature is free to turn and no relative force is transmitted ... drag. See also Electromagnetic brake References reflist External links Commons cat Electromagnetic ... more details
called the visible spectrum . The photon is the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation and is also the force carrier for the electromagneticforce. Electromagnetic radiation carries energy sometimes called ...Electromagnetism cTopic Classical electromagnetism Electrodynamics Electromagnetic radiation often abbreviated ... . Electromagnetic radiation is classified according to the frequency of its wave. The electromagnetic ... electromagnetic radiation absorption of electromagnetic radiation . Physics Theory File VisibleEmrWavelengths.svg thumb Shows the relative wavelengths of the electromagnetic waves of three different ... axis. main Maxwell s equations James Clerk Maxwell first formally postulated electromagnetic waves . These were subsequently confirmed by Heinrich Hertz . Maxwell derived a Electromagnetic wave equation ... field. In an electromagnetic wave, the changes induced by the electric field shift the wave in the magnetic ... direction. Together, these fields form a propagating electromagnetic wave. This view of propagating electromagnetic waves makes sense from a local perspective, ref name kinsler2011ejp cite journal .... ref name jefimenko2004ejp cite journal author Jefimenko, O. year 2004 title Presenting electromagnetic ... 10.1088 0143 0807 25 2 015 ref A Quantum mechanics quantum theory of the interaction between electromagnetic ... field in a horizontal plane File Electromagneticwave3Dfromside.gif thumb Electromagnetic ... left to right File Onde electromagnetique.svg thumb left 350px Electromagnetic waves can be imagined ... plane and the magnetic field in a horizontal plane. The physics of electromagnetic radiation is electrodynamics ... electromagnetic spectrum spectrum passing through a prism, because of the wavelength dependent ..., when electromagnetic radiation is absorbed by matter, particle like properties will be more ... dead link date November 2011 ref There are experiments in which the wave and particle natures of electromagnetic ... more details
Cleanup date June 2010 Electromagnetic radiation weapons are a type of directed energy weapon s which use electromagnetic radiation to deliver heat, mechanical, or electrical energy to a target to cause .... When used against equipment, directed electromagnetic energy weapons can operate similarly to omnidirectional electromagnetic pulse EMP devices, by inducing destructive voltage within electronic wiring ... EMP effects. When used against humans electromagnetic weapons can have dramatic effects, such as the intense ... include 1 the capability to influence an enemy force or population to flee rather than to stand and fight ... an enemy force of sound sleep for a prolonged period or 4 the capability to persuade the close ... officials having, say, airborne electromagnetic weapons at their disposal could covertly influence ... which the rioters could not pass without feeling unbearable pain. Using electromagnetic weapons ... of the harassment. By way of an electromagnetic signal directed toward her from a hidden microwave ... Research, conducted a study begun in 2004 called the Sensory Consequences of Electromagnetic ... to advance Classical electromagnetism electrodynamics and hypervelocity physics related to electromagnetic ... ref Use against humans Sometimes considered to be non lethal, electromagnetic weapons can, under the right ... Paper No. 34 Center for Strategy and Technology Air War College Air University Maxwell Air Force ... csat34.pdf non lethal weapons, electromagnetic weaponry poses health threats to humans&hl en&ct clnk&cd 2&gl us ref Some bio effects of electromagnetic radiation weapons include effects to the human ... breathing, vertigo, incontinence, nausea, disorientation, or other systemic discomfort. Electromagnetic radiation weapons may cause cumulative damage to the human body. Electromagnetic weapons can ... Forbes.com ref Electromagnetic weapons, including high power microwaves, were used during the Gulf .... The degree of exposure to electromagnetic fields by Iraqi civilians and battlefield troops is unknown ... more details
Electromagnetic mass was initially a concept of classical mechanics , denoting as to how much the electromagnetic ... forms of energy, including electromagnetic energy, is interpreted on the basis of Albert Einstein ... concerning the electromagnetic mass and self energy of charged particles are still studied. Charged ... sphere moving in a space filled with a medium of a specific inductive capacity the electromagnetic ... some sort of momentum and apparent electromagnetic mass, which can increase the ordinary mechanical mass of the bodies, or in more modern terms, the increase should arise from their electromagnetic self ... to the electron by using the Abraham Lorentz force . Now, the electrostatic energy math E em math and mass ... accumulation. Thus the formula for this electromagnetic energy mass relation is math m em frac 4 3 ... that the total mass of the bodies is identical to its electromagnetic mass. Wien stated, that if it is assumed that gravitation is an electromagnetic effect too, then there has to be a proportionality between electromagnetic energy, inertial mass, and gravitational mass. When one body attracts another one, the electromagnetic energy store of gravitation is according to Wien diminished by the amount ... that when mass is in fact the product of the electromagnetic field in the aether implying that no real ... Thomson 1893 noticed that electromagnetic momentum and energy of charged bodies and therefore ... beyond that of light. In 1897, Searle gave a more precise formula for the electromagnetic energy ... physicist Walter Kaufmann 1901 and Abraham 1902 derived the formula for the electromagnetic mass of moving ... is only valid in the longitudinal direction longitudinal mass , i.e., that the electromagnetic ... and 4 3 problem The idea of an electromagnetic nature of matter, however, had to be given up. Abraham 1904, 1905 ref name abraham04 argued that non electromagnetic forces were necessary to prevent ... electromagnetic mass can be obtained in Lorentz ether theory Lorentz s theory , depending ... more details
Interventions infobox Name Electromagnetic therapy Image Caption ICD10 ICD10PCS 6A2 6 A 2 ICD9 MeshID D055909 OPS301 OtherCodes HCPCSlevel2 Electromagnetic therapy or Electromagnetic field therapy refers to therapy involving the use of magnet s or electromagnets . Types include Bioelectromagnetics , the study of how electromagnetic fields interact with and influence biological processes. Electrotherapy , the use of electrical or electromagnetic energy in medicine Electromagnetic therapy alternative medicine , the use of electromagnetic radiation to treat disease. Evidence of efficacy is lacking. Pulsed Electromagnetic Field Therapy , or PEMF , the use of weak electromagnetic fields to initiate osteogenesis . See also Magnet therapy , use of static magnetic field s with the aim of treating disease. Evidence of efficacy is lacking. Extracorporeal assistance, performance, and therapy medicine stub Category Medical procedures Category Electromagnetism ... more details
at right angles to magnetic flux in accordance with Lorentz force. ref Friauf, J. B. 1961 . Electromagnetic ...Electromagnetic propulsion EMP , is the principle of accelerating an object by the utilization of a flowing electrical current and magnetic fields. The electric current electrical current is used to either ... known that when a current flows through a electrical conductor conductor in a magnetic field, an electromagneticforce known as a Lorentz force , pushes the conductor in a direction perpendicular to the conductor and the magnetic field. This repulsing force is what causes propulsion in a system designed to take advantage of the phenomenon. The term electromagnetic propulsion EMP can be described by its individual components electromagnetic using electricity to create a magnetic field electromagnetism ... of electromagnetic propulsion does not have origins with any one individual and has applications .... History One of the first recorded discoveries regarding electromagnetic propulsion was in 1889 when Professor Elihu Thomson made public his work with electromagnetic waves and alternating ... these principles and introduced the first practical application of electromagnetic propulsion. ref ... km h. Guinness World Records authorization. Electromagnetic propulsion is utilized in transportation ... katesix There is an air gap between these two parts that creates the frictionless property an electromagnetic ... of a linear induction motor begins with an AC force that is supplied to the coil windings ... fields in the primary coil assembly and reaction plate alternate, which generates force and direct ... interactions of the vehicle s own electromagnetic field and the magnetic field of the earth. The thrust force may be thought of as an electrodynamic force of interaction of the electric current ... a greater force of interaction, the magnetic field must be propagated further from the flight craft. The advantages of such systems is the very precise and instantaneous control over the thrust force ... more details
In telecommunication , electromagnetic survivability is the ability of a system , subsystem, or equipment to resume functioning without evidence of Degradation telecommunications degradation following temporary exposure to an adverse electromagnetic environment . The system, subsystem, or equipment performance may be degraded during exposure to the adverse electromagnetic environment, but the system will not experience permanent damage, such as electronic component component burnout, that will prevent proper operation when the adverse electromagnetic environment is removed. References FS1037C MS188 Category Telecommunications telecommunications stub ... more details
safety is an important consideration. ref phillips Holding force A magnetic lock has a metal plate surrounded by a coil of wire that can be magnetized. The number of coils determines the holding force which characterizes the lock Micro Size convert 300 lbf N abbr on lk on holding force. Mini Size convert 600 lbf N abbr on holding force Midi Size convert 800 lbf N abbr on holding force Standard Size convert 1200 lbf N abbr on holding force. The standard size electromagnetic lock is used as a gate ...For a lock utilizing magnetism and a key magnetic keyed lock An electromagnetic lock , magnetic lock , or maglock is a lock device locking device that consists of an electromagnet and an armature plate. By attaching the electromagnet to the door frame and the armature plate to the door, a Electric current current passing through the electromagnet attracts the armature plate, holding the door shut. Unlike an electric strike a magnetic lock has no interconnecting parts and is therefore not suitable for high security applications because it is possible to bypass the lock by disrupting the power supply ... assembly The electromagnetic lock was patented on May 2, 1989, by Arthur, Richard and David Geringer ... pull electromagnetic lock and was an improvement on a 1984 patent cited in the same document. Operation ... it consists of an electromagnet attracting a conductor with a force large enough to prevent the door ... B frac mu 0 mu rIN l math The force math F math between the electromagnet and the armature plate with surface .... For example, the force of the lock is proportional to the square of the relative permeability of the magnetic ... the door and lock. The principle behind the electromagnetic lock is to use electromagnetism to maintain ... force should be a collinear load and the lock and armature plate should be face to face in the correct ... force. When the current is fixed, voltage is proportional to power consumption. Application ... situations. References No footnotes date July 2011 note uspto Geringer A. Geringer R. Geringer D. Electromagnetic ... more details
Electromagnetic Suspension EMS is the magnetic levitation of an object achieved by constantly altering the strength of a magnetic field produced by electromagnets using a feedback loop . In most cases the levitation effect is mostly due to permanent magnets since they don t have any power dissipation, with electromagnets only used to stabilise the effect. A charged body cannot rest in stable equilibrium when placed in a pure electrostatic field or magnetostatic field. In these kinds of fields an unstable equilibrium condition exists. Although static fields cannot give stability, EMS works by continually altering the current sent to electromagnets to change the strength of the magnetic field and allows a stable levitation to occur. In EMS a feedback loop which continuously adjusts one or more electromagnets to correct the object s motion is used to cancel the instability. Many systems use magnetic attraction pulling upwards against gravity for these kinds of systems as this gives some inherent ..., University of Sussex. Electromagnetic Suspension and Levitation. ref Likewise, due to limitations ... extension and stabilized magnetic force by controlling current intensity and turning on and off ... service was opened in Birmingham, England in 1984, using electromagnetic suspension, and a linear ... and Applied Sciences, University of Sussex. Electromagnetic Suspension and Levitation. ref To reduce average power requirements, often the electromagnetic suspension is used only to stabilise the levitation ... is suspended on a guiding rail by the principle of electromagnetic suspension. Maglev has the advantages ... main Active magnetic bearing An active magnetic bearing AMB works on the principle of electromagnetic ... or Digital signal processor DSP . Electromagnetic Suspension Device for wheeled transports ... references External links BOSE Electromagnetic Suspension http www.bose.com controller?url automotive bose suspension index.jsp http magnetbahnforum.de index.php?inventors DEFAULTSORT Electromagnetic ... more details
Image Electromagnetic oscillograph img 1647.jpg thumb An electromagnetic oscillograph is an oscillograph which measures variations of electric current by having it go through a magnetic coil. Variations in current induce momentum in the coil, which can be directly measured. The electromagnetic oscillograph was invented by William Duddell . Some models utilise a mirror which reflects a beam of light, allowing measurement of minute movements of the coil. Other were fitted with a hand, possibly fitted with a pen to record values. External links http chem.ch.huji.ac.il history duddell.html William du Bois Duddell http www.freepatentsonline.com 2466691.html Electromagnetic oscillograph Category Measuring instruments Category British inventions ... more details
electromagnetism cTopic Classical electromagnetism Electrodynamics Electromagnetic induction is the production of an electric current across a Electrical conductor conductor moving through a magnetic field . It underlies the operation of electrical generator generator s, transformer s, induction motor s, electric motor s, synchronous motor s, and solenoid s. Citation needed date September 2011 Michael Faraday is generally credited with the discovery of induction in 1831 though it may have been anticipated by the work of Francesco Zantedeschi in 1829. Citation needed date April 2007 Around 1830 ref cite web author date title Magnets url http library.thinkquest.org 13526 c3c.htm publisher Oracle Thinkquest ThinkQuest accessdate 2009 11 06 ref to 1832 ref cite web author date title Joseph Henry url http www.nndb.com people 671 000096383 publisher NNDB Notable Names Database accessdate 2009 11 06 ref Joseph Henry made a similar discovery, but did not publish his findings until later. Overview Main Faraday s law of induction Michael Faraday stated that electromotive force EMF produced around a closed path is proportionality mathematics proportional to the rate of change of the magnetic flux through any surface bounded by that path. In practice, this means that an electric current will be induced in any closed Electrical network circuit when the magnetic flux through a surface bounded by the conductor changes. This applies whether the field itself changes in strength or the conductor ... mathcal E d Phi B over dt , math where math scriptstyle mathcal E math is the electromotive force ... PA20 Extract of page 20 ref Applications The principles of electromagnetic induction are applied in many devices and systems, including columns list 3 Current clamp Electrical generator s Electromagnetic ... physics Two videos demonstrating Faraday s and Lenz s laws at EduMation DEFAULTSORT Electromagnetic ... simple Electromagnetic induction sk Elektromagnetick indukcia sl Elektromagnetna ... more details
for example, Electromagnetic forming An electromagnetic pulse sometimes abbreviated EMP is a burst of electromagnetic radiation . The abrupt pulse of electromagnetic radiation usually results from certain ... altitude electromagnetic pulse HEMP device. Effects of a HEMP device depend on a very large ... ray output, interactions with the Earth s magnetic field , and electromagnetic shielding of targets. History The fact that an electromagnetic pulse is produced by a nuclear explosion was known since ... to Enrico Fermi Enrico Fermi s expectation of an electromagnetic pulse from the detonation. The official .... ref name baum1 Baum, Carl E., Reminiscences of High Power Electromagnetics , IEEE Transactions on Electromagnetic ... notes History BaumReminiscences.pdf ref ref name baum2 Baum, Carl E., From the Electromagnetic ... nuclear electromagnetic pulse in 1981 by William Broad William J. Broad in the weekly publication ... electromagnetic pulse data that was clear enough to enable physicists to accurately identify the physical mechanisms that were producing the electromagnetic pulses. ref name nbcreport Longmire ... extinguished ref Rabinowitz, Mario 1987 Effect of the Fast Nuclear Electromagnetic Pulse on the Electric ... exists ref Greetsai, Vasily N., et al. Response of Long Lines to Nuclear High Altitude Electromagnetic Pulse HEMP IEEE Transactions on Electromagnetic Compatibility, Vol. 40, No. 4, November 1998 ... Loborev, Vladimir M. Up to Date State of the NEMP Problems and Topical Research Directions , Electromagnetic ... a non nuclear electromagnetic pulse was conceived as early as 1951 by Andrei Sakharov in the Soviet ... of nuclear EMP The case of a nuclear electromagnetic pulse differs from other kinds of electromagnetic pulse EMP in being a complex electromagnetic multi pulse. The complex multi pulse is usually ... www.iec.ch cgi bin procgi.pl www iecwww.p?wwwlang E&wwwprog cat det.p&wartnum 020728 Electromagnetic ... component is a very brief but intense electromagnetic field that can quickly induce very high voltages ... more details
An Electromagnetism electromagnetic cavity is a cavity that acts as a container for electromagnetic field s such as photon s, in effect containing their wave function inside. The size of the cavity determines the maximum photon wave length that can be trapped. Additionally, it produces quantized energy level s for trapped charged particles like electrons and protons . The earth s magnetic field in effect places the earth in an electromagnetic cavity. Physical description of electromagnetic cavities Electromagnetic cavities are represented by potential well s, also called boxes , which can be of limited or unlimited depth V sub 0 sub . Quantum mechanic boxes are described by the time independent Schr dinger equation div align center math left frac hbar 2 2m nabla 2 V mathbf r right psi mathbf r E psi mathbf r math div with the additional boundary condition s the wave function is confined to the box infinite deep potential well or approaches zero as the distance from the wall increases to infinity, thus normalisable the wave function must be continuous function continuous the derivative of the wave function must be continuous which leads to real solutions for the wave functions if the net energy of the particle is negative., i.e. if the particle is in a bound state . Applications of electromagnetic cavities Electrons which are trapped in an electromagnetic cavity are in a bound state and thus organise themselves as they do in a regular atom , thus expressing chemical like behaviour. Several researchers have proposed to develop programmable matter by varying the number of trapped electrons in those cavities. http www.wired.com wired archive 9.10 atoms.html The discrete energy levels of electromagnetic cavities are exploited to produce photons of desired frequencies and thus are essential for nano or submicrometre scale laser devices. See also Cavity resonator Crab cavity Schumann resonance Optical cavity Quantum dot Category Electromagnetism ... more details
Electromagnetic Testing ET , as a form of nondestructive testing , is the process of inducing electric current s or magnetic field s or both inside a test object and observing the electromagnetism electromagnetic response. If the test is set up properly, a defect inside the test object creates a measurable response. The term Electromagnetic Testing is often intended to mean simply Eddy Current Testing ECT . However with an expanding number of electromagnetic and magnetic test methods, Electromagnetic Testing is more often used to mean the whole class of electromagnetic test methods, of which Eddy Current Testing is just one. Common Methods of Electromagnetic Testing Eddy Current Testing ECT is used to detect near surface cracks and corrosion in metallic objects such as tubes and aircraft fuselage and structures. ECT is more commonly applied to nonferromagnetic materials, since in ferromagnetic materials the skin effect depth of penetration is relatively small. Remote field testing RFT is used for nondestructive testing NDT of steel tubes and pipes. Magnetic flux leakage Magnetic flux leakage testing MFL is also used for nondestructive testing NDT of steel tubes and pipes. At present RFT is more commonly used in small diameter tubes and MFL in larger diameter pipes over long travel distances. Wire rope testing is MFL applied to steel cables, to detect broken strands of wire. Magnetic particle inspection MT or MPI is a form of MFL where small magnetic particles in the form of a powder or liquid are sprayed on the magnetized steel test object and gather at surface breaking cracks. Alternating Current Field Measurement ACFM is similar to eddy current applied to steel. Its most ... without removing insulation. References Hugo L. Libby, Introduction to Electromagnetic Nondestructive .... 5, http www.asnt.org publications handbook third 3et.htm Electromagnetic Testing . William Lord, http www.asnt.org publications materialseval June06d.pdf Electromagnetic NDT Techniques A 40 Year ... more details
Orphan date February 2009 An Electromagnetism Electromagnetic Log , sometimes called an EM Log , measures the speed of a vessel through water. It operates on the principle that when a Electrical conductor conductor such as water passes through an electromagnetic field, a voltage is created and the amount of voltage created increases as the speed of the conductor increases. The process is the EM Log creates an electromagnetic field . a voltage is induced in the water the magnitude of the voltage varies depending upon the speed of the water flow past the sensor. the EM Log measures the voltage created and translates this into the vessel s speed through water. Advantages No moving parts Disadvantages Salinity and temperature of water effects calibration Measurements effected by boundary layer, water speed slowed down close to the hull by friction External links http thenauticalsite.com NauticalNotes EchoSpdLog MyEchoSpdLog Lesson02 SpeedLogs.htm http www.yokogawa.com ydk mr marine emlog index.htm http www.agiltd.co.uk marine instrumentation agilog speed log Category Navigational equipment electronics stub ... more details
Electromagnetic Diaphragm is a form of capacitive sensor used on an electronic stethoscope . The diaphragm is coated with a Electric conduction conductive material . Behind the diaphragm, a conductive plate is positioned behind and parallel to the diaphragm, so that the two conductive elements form a capacitor . Capacitance is a function of plate area, dielectric properties of the space between the conductors, and the distance between the conductors. It is this latter parameter which is modulated by vibration such that the capacitance varies with the distance between the Electromagnetism electromagnetic diaphragm and the plate, forming an acoustic sensor. ref name Thinklabs cite web url http www.thinklabsmedical.com electronic stethoscope technology electromagnetic diaphragm emd 102.html title Electromagnetic Diaphragm EmD publisher thinklabsmedical.com work Thinklabs accessdate June 04, 2011 ref The electromagnetic diaphragm is a form of capacitive sensor, and shares properties with condenser microphone s. The difference between the electromagnetic diaphragm and a condenser microphone is that a condenser microphone operates on the basis of air transmission, has a very thin membrane instead of a diaphragm, and cannot be placed against a body to sense sounds within the body. ref name Thinklabs The electromagnetic diaphragm for stethoscopes was patented by Clive Smith in 2002 and is used on Thinklabs electronic stethoscopes. ref cite web url http patft.uspto.gov netacgi nph Parser?Sect1 PTO2&Sect2 HITOFF&p 1&u 2Fnetahtml 2FPTO 2Fsearch bool.html&r 2&f G&l 50&co1 AND&d PTXT&s1 22transducer sensing body sounds 22&OS 22transducer sensing body sounds 22&RS 22transducer sensing body sounds 22 title Transducer for sensing body sounds publisher patft.uspto.gov date December 9, 2003 accessdate June 04, 2011 ref ref cite web url http patft.uspto.gov netacgi nph Parser?Sect1 PTO2&Sect2 HITOFF&p 1&u 2Fnetahtml 2FPTO 2Fsearch bool.html&r 1&f G&l 50&co1 AND&d PTXT&s1 22transducer sensing ... more details
Idiopathic environmental intolerance attributed to electromagnetic fields IEI EMF is a set of claims of adverse medical symptoms purportedly caused by exposure to electromagnetic field s. ref name who Other terms for IEI EMF include electromagnetic hypersensitivity EHS , electrohypersensitivity , electro sensitivity , and electrical sensitivity ES . Although the thermal effects of electromagnetic fields on the body are established, self described sufferers of electromagnetic hypersensitivity report responding to non ionizing electromagnetic fields or electromagnetic radiation at intensities well ... have found that self described sufferers of electromagnetic hypersensitivity are unable to distinguish between exposure to real and fake electromagnetic fields, ref name RubinProvReview2005 ref name ... conducted a workshop on electromagnetic hypersensitivity. ref http www.who.int peh emf publications ... lines 27 . The survey was not designed to find any causal connection between electromagnetic ... to electromagnetic field exposure a questionnaire survey journal Int J Hyg Environ Health volume 207 ... Environmental Intolerance . ref name irvine2005 Levitt proposed ties between electromagnetic ... , and Autism . ref Cite book last Levitt first B. Blake authorlink coauthors title Electromagnetic ... evidence that electromagnetic field sensitivity exists . ref name rea1991 Cite journal last Rea ... Samadi, Gerald Ross title Electromagnetic field sensitivity journal Journal of Bioelectricity volume ... id accessdate ref Those reporting electromagnetic hypersensitivity will usually describe different levels of susceptibility to electric field s, magnetic field s and various frequencies of electromagnetic ... es.asp Electromagnetic hypersensitivity EHS a modern illness ref Other surveys of electromagnetic ... reflecting almost every part of the body have been attributed to electromagnetic field exposure. A minority of people who report electromagnetic hypersensitivity claim to be severely affected by it. For instance ... more details
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