Search results
Results from the WOW.Com Content Network
A portative electromagnet is one designed to just hold material in place; an example is a lifting magnet. A tractive electromagnet applies a force and moves something. [8] Electromagnets are very widely used in electric and electromechanical devices, including: Motors and generators; Transformers; Relays; Electric bells and buzzers ...
The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electrostatics and magnetism, which are distinct but closely intertwined phenomena. Electromagnetic forces occur between any two charged particles.
Inductance — The phenomenon whereby the property of a circuit by which energy is stored in the form of an electromagnetic field. Induction heating — Heat produced in a conductor when eddy currents pass through it. Joule heating — Heat produced in a conductor when charges move through it, such as in resistors and wires.
Maxwell's equations further indicated that electromagnetic waves existed, and the experiments of Heinrich Hertz confirmed this, making radio possible. Maxwell also postulated, correctly, that light was a form of electromagnetic wave, thus making all of optics a branch of electromagnetism.
Eddy currents in conductors of non-zero resistivity generate heat as well as electromagnetic forces. The heat can be used for induction heating. The electromagnetic forces can be used for levitation, creating movement, or to give a strong braking effect. Eddy currents can also have undesirable effects, for instance power loss in transformers.
A solenoid (/ ˈ s oʊ l ə n ɔɪ d / [1]) is a type of electromagnet formed by a helical coil of wire whose length is substantially greater than its diameter, [2] which generates a controlled magnetic field. The coil can produce a uniform magnetic field in a volume of space when an electric current is passed through it.
Ancient people learned about magnetism from lodestones (or magnetite) which are naturally magnetized pieces of iron ore.The word magnet was adopted in Middle English from Latin magnetum "lodestone", ultimately from Greek μαγνῆτις [λίθος] (magnētis [lithos]) [1] meaning "[stone] from Magnesia", [2] a place in Anatolia where lodestones were found (today Manisa in modern-day Turkey).
The shape of the magnet was originally created as a replacement for the bar magnet as it makes the magnetic field stronger for a magnet of comparable strength. [5] A horseshoe magnet is stronger because both poles of the magnet are closer to each other and in the same plane which allows the magnetic lines of flux to flow along a more direct path between the poles and concentrates the magnetic ...