1. Electromagnetism - Wikipedia, The Free Encyclopedia electromagnetism is the physics of the electromagnetic field a field which exerts a force on particles that possess the property of electric charge, http://en.wikipedia.org/wiki/Electromagnetism

Electromagnetism From Wikipedia, the free encyclopedia Jump to: navigation search Electromagnetism Electricity Magnetism Electrostatics Electric charge ... edit Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge , and is in turn affected by the presence and motion of those particles. A changing magnetic field produces an electric field (this is the phenomenon of electromagnetic induction , the basis of operation for electrical generators induction motors , and transformers ). Similarly, a changing electric field generates a magnetic field. Because of this interdependence of the electric and magnetic fields, it makes sense to consider them as a single coherent entity—the electromagnetic field. The magnetic field is produced by the motion of electric charges, i.e. electric current . The magnetic field causes the magnetic force associated with magnets The theoretical implications of electromagnetism led to the development of special relativity by Albert Einstein in Contents History The electromagnetic force Classical electrodynamics The photoelectric effect ... edit History While preparing for an evening lecture on 21 April 1820

2. Electromagnetism electromagnetism describes the relationship between electricity and magnetism. Nearly everyone, at some time or another, has had the opportunity to play http://www.eas.asu.edu/~holbert/wise/electromagnetism.htm

Electromagnetism What is Electromagnetism? Electromagnetism describes the relationship between electricity and magnetism. Nearly everyone, at some time or another, has had the opportunity to play with magnets. Most of us are acquainted with bar magnets or those thin magnets that usually end up on refrigerators. These magnets are known as permanent magnets. Although permanent magnets receive a lot of exposure, we use and depend on electromagnets much more in our everyday lives. Electromagnetism is essentially the foundation for all of electrical engineering. We use electromagnets to generate electricity, store memory on our computers, generate pictures on a television screen, diagnose illnesses, and in just about every other aspect of our lives that depends on electricity. Electromagnetism works on the principle that an electric current through a wire generates a magnetic field. This magnetic field is the same force that makes metal objects stick to permanent magnets. In a bar magnet, the magnetic field runs from the north to the south pole. In a wire, the magnetic field forms around the wire. If we wrap that wire around a metal object, we can often magnetize that object. In this way, we can create an electromagnet. Experiments Involving Electromagnetism In order to find out more about electromagnetism, and do an experiment of your own, click on one of the pictures below. Try making your own:

3. Electromagnetism General electromagnetic theory, including static field equations, the origins of inductance, and EMR. http://www.mariner.connectfree.co.uk/html/electromagnetism.html

Electromagnetism Home Electromagnetic Inertia Have you ever thought “If an electron induces a magnetic field when it moves, and magnetic fields contains energy, where does the energy to create this field come from?” Click here to find out more about Electromagnetic Inertia. Electrostatic Potential Energy The starting point for all electrostatic interactions is that between two point electric charges such as two electrons, or between a positron and an electron. In the 19th century scientists did not understand the interaction, and invented the concept of “potential energy” to provide the force that drove these particles together or apart. It was only when Einstein developed the equivalence of mass and energy that the true source of the energy became apparent. You are probably familiar with the concept that electric fields contain energy and it is the interaction between the fields of the two charges that leads to changes in their energy and hence to the forces between them, energy being simply the integral of force over distance. This paper develops the equations for the interaction at any point in space near the charges, without recourse to “potential energy”. Click here to view the paper on electrostatic fields and the associated potential energy.

4. Electromagnetism - Succeed In Physical Science: School For Champions Explanation of how electromagnetism is created Succeed in Physical Science School for Champions. http://www.school-for-champions.com/science/electromagnetism.htm

The School for Champions is an educational website that shows you how to achieve your dreams. Search site SfC Home Physical Science Explanation of how Electromagnetism is created - Succeed in Physical Science. Also refer to physics, magnetism, electromagnet, magnet, electricity, electrons, AC, DC, forces, compass, poles, iron, battery, Tesla, gauss, Ron Kurtus, School for Champions. Electromagnetism by Ron Kurtus (revised 3 April 2005) An electromagnet is an object that acts like a magnet, but its magnetic force is created and controlled by electricitythus the name electromagnet . By wrapping insulated wire around a piece of iron and then running electrical current through the wire, the iron becomes magnetized. This happens because a magnetic field is created around a wire when it has electrical current running through it. Creating a coil of wire concentrates the field. Wrapping the wire around an iron core greatly increases the strength of the magnetic field. Questions you may have include: How can you make an electromagnet?

5. Chapter 2: Electromagnetism For more information on electromagnetism, see the Recommended Reading section. Order super magnets here. Del.icio.us http://sci-toys.com/scitoys/scitoys/electro/electro.html

Scitoys.com Ingredients Science Blog Science Toys ... Build a digital thermometer A motor in 10 minutes Back in the 1960's my father taught me how to make the little electric motor we will make here. Sometime in the 1980's I saw a description of it in the magazine "Physics Teacher". Lately I have seen it described as Beakman's motor, after the science oriented TV show on which it recently appeared. The motor is simply a battery, a magnet, and a small coil of wire you make yourself. There is a secret to making it (which I will of course share with you) which is at the same time clever and delightfully simple. What you will need: A battery holder, such as Radio Shack #270-402 (holds a "C" cell) or #270-403 (holds a "D" cell). A battery to fit the holder. A magnet such as Radio Shack #64-1877, #64-1895, #64-1883, #64-1879, or #64-1888. Some magnet wire such as Radio Shack #278-1345. We want enamel coated 22 gauge (or thicker) wire. We will only need about a yard of wire, so the Radio Shack package will make a dozen motors or more. Some heavier wire such as Radio Shack #278-1217 or #278-1216. We want bare wire of 18 or 20 gauge, so we will be removing the plastic insulation from the wires listed above. We will need less than a foot of this wire per motor.

6. Electromagnetism The electromagnetic force causes likecharged things to repel and oppositely-charged things to attract. Many everyday forces, such as friction, http://particleadventure.org/frameless/electromagnetism.html

What Holds it Together? Electromagnetism The electromagnetic force causes like-charged things to repel and oppositely-charged things to attract. Many everyday forces, such as friction, and even magnetism, are caused by the electromagnetic, or E-M force. For instance, the force that keeps you from falling through the floor is the electromagnetic force which causes the atoms making up the matter in your feet and the floor to resist being displaced. The carrier particle of the electromagnetic force is the photon ). Photons of different energies span the electromagnetic spectrum of x rays, visible light, radio waves, and so forth. Photons have zero mass, as far as we know, and always travel at the "speed of light", c, which is about 300,000,000 meters per second, or 186,000 miles per second, in a vacuum.

7. Teaching Electromagnetism Using Advanced Technologies: John W. Belcher MIT Michael Faraday was the first to realize that the shape of electromagnetic field lines is extraordinarily expressive of their dynamical effects. http://web.mit.edu/jbelcher/www/anim.html

Teaching Electromagnetism Using Advanced Technologies This is an early site. Our animations have gotten much much MUCH better. Go to this link for our later material. Animations created using Discreet's 3D Studio MAX This work is supported by NSF Grant #9950380 , an MIT Class of 1960 Fellowship, The Helena Foundation, the MIT Classes of 51 and 55 Funds for Educational Excellence, the MIT School of Science Educational Initiative Awards, and MIT Academic Computing. Faraday's Law (3.3 Meg QT) and Creating A Dipole (3.0 Meg QT) A Paper On The Mathematics Of These Animations A Description of the TEAL/Studio Project at MIT (pdf file) Michael Faraday was the first to realize that the shape of electromagnetic field lines is extraordinarily expressive of their dynamical effects. We can understand intuitively many things about the forces transmitted by the fields by looking at the topology of the field lines. This is especially true when the field lines are animated. The examples given here are only a few of many (if you do not have a movie player, download QuickTime 3 to view both avi and quicktime files) Experiments and Animations: Faraday's Law Electrostatics Radiation Magnetostatics ... , Developer) Physics and mathematics by Professors John Belcher and Stanislaw Olbert. 3D modeling/animations and Physics demonstrations by Mark Bessette. MAX scripting by Larry Minton.

8. VRML Gallery Of Electromagnetism (by Rob Salgado) Syracuse University VRML Gallery of electromagnetism. http://physics.syr.edu/courses/vrml/electromagnetism/

http://physics.syr.edu/courses/vrml/electromagnetism/ Module Content Last modified: 12 Oct 1996 Homepage Last modified: Sat Aug 18 17:50:07 2001 VRML Browser links updated: Apr 27 2006 VRML 2.0 VRML 1.0-gz VRML 1.0 VRML Gallery of Electromagnetism Rob Salgado (salgado@physics.syr.edu) Ampere's Law anim (255 kb) Assorted anim (940 kb) A line-integral (166 kb) These pages are some of my attempts to visualize the vector fields (actually differential forms) of electromagnetism. These images are inspired by the works of the authors in my references. i have updated these links These visualizations require a VRML-enabled browser. more VRML browsers best viewed with CosmoPlayer information from Karmanaut CosmoPlayer at NIST CosmoPlayer installation advice or WorldView or Blaxxun or Cortona or my new favorite: GLView (Mac: Zaptech BeOS: Breeze Linux et al... build your own: OVAL With help from Sun's Java3D Try this new Shout3D version of my Electric Dipole Since September 30, 1996, you are visitor number Addition Addition: Vector Addition: 1-Form Addition: 2-Form Wedge Product Wedge Product: Vector/Bivector Wedge Product: 1-Form/2-Form Raising and Lowering of Indices Raising and Lowering: Vector/1-Form Raising and Lowering: Bivector/2-form Unit Vectors x-hat y-hat z-hat r-hat Charged Point (Coulomb) Charged Point: Electric Vector Charged Point: Electric 1-form Charged Point: Electric twisted 2-form (vector density) Two Charged Points Two Charged Points: Electric Vector Two Charged Points: Electric 1-form Two Charged Points: Electric twisted 2-form (vector density) Charged Dipole

9. Electromagnetism: Definition And Much More From Answers.com electromagnetism n. Magnetism produced by electric charge in motion. The physics of electricity and. http://www.answers.com/topic/electromagnetism

BodyLoad('s'); On this page: Select Article Dictionary Sci-Tech Encycl. Britannica Concise Veterinary Electronics Wikipedia Or search: - The Web - Images - News - Blogs - Shopping Dictionary electromagnetism Ä­-lĕk trō-măg nÄ­-tÄ­z əm Also from Answers.com... Allergies Health videos on seasonal allergies, including allergy treatment options. document.getElementById("videoBox").style.display="block" n. Magnetism produced by electric charge in motion. The physics of electricity and magnetism. ADVERTISEMENT Home Business Entertainment Food ... More... InitForm('lookup1','autodiv1','down'); Library Arts Business Entertainment Food ... Sci-Tech Encyclopedia Electromagnetism The branch of science dealing with the observations and laws relating electricity to magnetism. Electromagnetism is based upon the fundamental observations that a moving electric charge produces a magnetic field and that a charge moving in a magnetic field will experience a force. The magnetic field produced by a current is related to the current, the shape of the conductor, and the magnetic properties of the medium around it by Amp¨re's law. The magnetic field at any point is described in terms of the force that it exerts upon a moving charge at that point. The electrical and magnetic units are defined in terms of the ampere , which in turn is defined from the force of one current upon another. The association of electricity and magnetism is also shown by electromagnetic induction, in which a changing magnetic field sets up an electric field within a conductor and causes the charges to move in the conductor.

10. Electromagnetism Authors web pages for the textbook electromagnetism , by GL Pollack and DR Stump, published by AddisonWesley. http://www.pa.msu.edu/~stump/EM/

Electromagnetism by G L Pollack and D R Stump Published by Addison Wesley The site contains free materials supplementary to the textbook, including chapter summaries, useful tables, self-test questions and answers, and some additional items. To read the files you will need Adobe Acrobat Reader. Useful Tables Vector derivatives in Cartesian, cylindrical and spherical coordinates Vector identities Physical constants and other quantities The Maxwell equations and other equations of electromagnetism ... Acknowledgement of Reviewers The authors Dan Stump stump@pa.msu.edu Jerry Pollack pollack@pa.msu.edu

11. MSci Electromagnetism : Lecture Notes Lecture Notes 10 The Lagrangian and Hamiltonian for a charged particle and the electromagnetic field, the canonical and symmetric stress tensors, http://www.strings.ph.qmul.ac.uk/~bill/emt/LecNotes.html

Lecture Notes The following notes (in PDF format) summarise the course. More detailed discussion of this material will be presented in the lectures, and the course of the lectures may not follow exactly that of the notes. Lecture Notes 7 and 8 will be covered in one week. There will be some revision of these notes during the 2006/7 course in order to match the lectures more closely. Lecture Notes 1 : Historical background, vector calculus, Maxwell's equations, energy and momentum. Magnetic monopoles. Lecture Notes 2 : Linear media, polarisation and magnetisation, Maxwell's equations in matter, boundary conditions, energy and momentum, the Clausius-Mossotti relation, solved problems. Lecture Notes 3 : Plane waves, polarisation, dispersion, the Kramers-Kronig relations. Lecture Notes 4 : Scalar and vector potentials, the inhomogeneous wave equation, the delta function, the Green function. Lecture Notes 5 : Radiation from a generalised localised source, electric dipole radiation, magnetic dipole radiation and higher order terms, radiation from an antenna. Lecture Notes 6 : Scattering, scattering from a small scatterer, many scatterers, scattering from the sky, the Born approximation, Rayleigh's explanation for the blue sky, critical opalescence, the optical theorem.

12. Electromagnetism We are now in a position which will allow us, at least qualitatively, to describe the origins of electromagnetic radiation and its interaction with atoms http://www.ch.ic.ac.uk/local/physical/mi_5.html

5 Electromagnetism 5.1 Magnetism So far we have discussed the forces between charges which are at rest with respect to each other. When charges are moving relative to each other they exert an additional force, the magnetic force. This force, as we will see later, plays a negligible role in inter atomic and intermolecular bonding. However, the effect of magnetic fields on atoms and molecules is used widely in all manner of spectroscopies, and we will need to appreciate magnetic behaviour in order to understand the interaction of light and other electromagnetic radiation with atoms and molecules. 5.1.1 The Lorentz Force Magnetic materials were discovered well before the electrostatic effects of rubbing amber. The magnetic iron oxide, magnetite, was mined in Asia Minor well before the birth of Christ, indeed by about 100 BC the Chinese had already discovered that such minerals would align with the north and south poles. By the beginning of the 19th Century it was known that such bar magnets would repel if like poles were facing each other and attract if the poles were of the opposite sense, and the similarities with the behaviour of electric charges had for some time interested scientists of the time. They made the following observations * the force is proportional to the magnitude and sign of the charge on the particle * the force is proportional to the velocity of the charged particle * the force is proportional to the magnitude of the magnetic field * the magnitude of the force depends on the relative orientation between the line of flight and the direction of the magnetic field

13. Electromagnetism -- Britannica Online Encyclopedia Britannica online encyclopedia article on electromagnetism science of charge and of the forces and fields associated with charge. Electricity and magnetism http://www.britannica.com/eb/article-9106021/electromagnetism

document.writeln(''); document.writeln('Initializing application...'); Username Password Remember me Forgot your password? Browse Shop Log In Search Site: electromagnetism physics Main science of charge and of the forces and fields associated with charge. Electricity and magnetism are two aspects of electromagnetism. Electric forces are produced by electric charges either at rest or in motion. Magnetic forces, on the other hand, are produced only by moving charges and act solely on charges in motion. Electric phenomena occur even in neutral matter because the forces act on the individual charged constituents. The electric force, in particular, is responsible for most of the physical and chemical properties of atoms and molecules. It is enormously strong compared with gravity . For example, the absence of only one electron out of every billion molecules in two 70-kilogram (154-pound) persons standing two metres (two yards) apart would repel them with a 30,000-ton force. On a more familiar scale, electric phenomena are responsible for the lightning and thunder accompanying certain storms. Electric and magnetic forces can be detected in regions called electric and magnetic fields. These fields are fundamental in nature and can exist in space far from the charge or current that generated them. Remarkably, electric fields can produce magnetic fields and vice versa, independent of any external charge. A changing magnetic field produces an electric field, as the English physicist Michael Faraday discovered in work that forms the basis of electric power generation. Conversely, a changing electric field produces a magnetic field, as the Scottish physicist James Clerk Maxwell deduced. The mathematical equations formulated by Maxwell incorporated light and wave phenomena into electromagnetism. He showed that electric and magnetic fields travel together through space as waves of

14. Electromagnetism Introduction to how magnets work, the history of magnets, types of magnets, Uses of magnets and electromagnetism. http://www.howmagnetswork.com/Electromagnetism.html

Electromagnetism How Magnets Work Earth's Magnetic Fields History of Magnets Industrial Magnet Uses Electromagnetism Types of Magnets Magnetic Effect Of Current Or Electromagnetism The term "magnetic effect of current" means that "a current flowing in a wire produces a magnetic field around it". The magnetic effect of current was discovered by Oersted in 1820. Oersted found that a wire carrying a current was able to deflect a magnetic needle. Now, a magnetic needle can only be deflected by a magnetic field. Thus it was concluded that a current flowing in a wire always gives rise to a magnetic field round it. The magnetic effect of current is called electromagnetism which means that electricity produces magnetism. Tenets Of Electromagnetism: Magnetic Field Pattern Due To Straight Current-Carrying Conductor The magnetic lines of force round a straight conductor carrying current are concentric circles whose centers lie on the wire. The magnitude of magnetic field produced by a straight current-carrying wire at a given point is: Directly proportional to the current passing in the wire, and

15. MIT OpenCourseWare | Electrical Engineering And Computer Science | 6.635 Advance This course features lecture notes and some MATLAB® demonstrations which help to illustrate the principles of electromagnetism. http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-635Advan

skip to content Home Courses Donate ... Electrical Engineering and Computer Science Advanced Electromagnetism 6.635 Advanced Electromagnetism Spring 2003 Maxwell's equations. (Image courtesy of MIT OCW.) Course Highlights lecture notes Course Description In 6.635, topics covered include: special relativity, electrodynamics of moving media, waves in dispersive media, microstrip integrated circuits, quantum optics, remote sensing, radiative transfer theory, scattering by rough surfaces, effective permittivities, random media, Green's functions for planarly layered media, integral equations in electromagnetics, method of moments, time domain method of moments, EM waves in periodic structures: photonic crystals and negative refraction. Technical Requirements Media player software, such as , or , is required to run the .mpeg files found on this course site. The latest version of can be used to run the .mp4 files in this section. Staff Instructor: Prof. Jin Au Kong Course Meeting Times Lectures: Two sessions / week 1.5 hours / session

16. Electromagnetism - Definition From The Merriam-Webster Online Dictionary Definition of electromagnetism from the MerriamWebster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. http://www.merriam-webster.com/dictionary/electromagnetism

Home Visit Our Sites Unabridged Dictionary Learner's Dictionary ... Contact Us Also Visit: Unabridged Encyclopedia Britannica Visual ESL: Learner's for Kids: Spell It! Word Central Dictionary Thesaurus Spanish/English Medical Search "electromagnetism" in: Thesaurus Spanish/English Medical Dictionary Open Dictionary Browse words next to: electromagnetism Browse the Dictionary: A B C D ... Z electromagnetism One entry found. electromagnetism Main Entry: Pronunciation: Function: noun Date:  magnetism developed by a current of electricity 2 a electromagnetic force gravity strong force weak force b  a branch of physical science that deals with the physical relations between electricity and magnetism Learn more about "electromagnetism" and related topics at Britannica.com See a map of "electromagnetism" in the Visual Thesaurus Pronunciation Symbols Products Premium Services ... Advertising Info

17. K12 Electromagnetism And Magnetism K12 electromagnetism and magnetism. Interaction between a magnet and a conductor through which flows a current. The thermal and chemical effects of an http://kr.cs.ait.ac.th/~radok/physics/k12.htm

Electromagnetism and magnetism Interaction between a magnet and a conductor through which flows a current The thermal and chemical effects of an electric current occur in the track of the current . Consider next actions of currents away from it . Just as electricity at rest has its electric field, so does the moving one; the environment of a conductor carrying a current exercises apparent distant action: Especially on nearby magnetic needles. A magnetic needle has at every point on Earth's surface a definite direction (in a definite magnetic meridian ) and, if you force it to turn elsewhere and then release it, it will always return to its initial direction. Apparently a force ( Earth's magnetism ) keeps the needle within the magnetic meridian; it requires work, to deflect it from it. Work of this kind can be performed by an electric current: It diverts the magnetic needle (first discovered by Oerstedt 1820) and thereby performs what only a magnet can do - in other words: Flowing electricity exerts magnetic forces . For the direction in which the current turns the needle you have the rule: Imagine you swim in the conductor

18. Electromagnetism electromagnetic force, a longrange force involving the electric and magnetic properties of elementary particles. It is responsible for the repulsion of http://www.neutron.anl.gov/hyper-physics/electrom.html

electromagnetic force , a long-range force involving the electric and magnetic properties of elementary particles . It is responsible for the repulsion of like and attraction of unlike electric charges and explains atomic structure and the properties of light and other forms of electromagnetic radiation. Two point charges will attract or repel each other according to Coulomb's law with a force that is directly proportional to the product of their charges and inversely proportional to the square of the distance between them: F=C·q ·q /r The electromagnetic interaction is mediated, or carried, by photons . Because its effects can be easily observed, electromagnetism is the most thoroughly studied and best understood of the four fundamental forces of nature . The same laws that govern electromagnetism on the subatomic scale also apply on a large scale in motors, generators, and electronic equipment. A moving electric charge gives rise to a magnetic field, and if its motion changes the magnetic field varies and in turn produces an electric field; this is the origin of electromagnetic radiation.

19. GCSE SCIENCE PHYSICS HIGH SCHOOL - Electromagnetism - All Links - Gcsescience.co gcsescience.com gcsescience.com. electromagnetism Magnets Straight Wire Electromagnetic Coil Bell Relay Circuit Breaker RCCB http://www.gcsescience.com/pme.htm

gcsescience.com gcsescience.com Electromagnetism Magnets Straight Wire ... Questions gcsescience.com Contents Index Quizzes gcsescience.com

20. Electromagnetism : MAGNETISM AND ELECTROMAGNETISM electromagnetism. The discovery of the relationship between magnetism and electricity was, like so many other scientific discoveries, stumbled upon almost http://www.allaboutcircuits.com/vol_1/chpt_14/2.html

Hilite.elementid = "main"; All About Circuits Volume I - DC Volume II - AC Volume III - Semiconductors ... Sitemap Search this site Table of Contents: Permanent magnets Electromagnetism Magnetic units of measurement Permeability and saturation ... PDF var addthis_pub = 'GFYGCMPH6Z132X8G'; Volume I - DC MAGNETISM AND ELECTROMAGNETISM Electromagnetism The discovery of the relationship between magnetism and electricity was, like so many other scientific discoveries, stumbled upon almost by accident. The Danish physicist Hans Christian Oersted was lecturing one day in 1820 on the possibility of electricity and magnetism being related to one another, and in the process demonstrated it conclusively by experiment in front of his whole class! By passing an electric current through a metal wire suspended above a magnetic compass, Oersted was able to produce a definite motion of the compass needle in response to the current. What began as conjecture at the start of the class session was confirmed as fact at the end. Needless to say, Oersted had to revise his lecture notes for future classes! His serendipitous discovery paved the way for a whole new branch of science: electromagnetics. Detailed experiments showed that the magnetic field produced by an electric current is always oriented perpendicular to the direction of flow. A simple method of showing this relationship is called the

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

Page 1     1-20 of 83    1  | 2  | 3  | 4  | 5  | Next 20