Information AboutElectrical |
| CATEGORIES ABOUT ELECTRICITY | |
| electricityelectricity | |
| electromagnetism | |
| energy | |
|
strikes during a night-time Thunderstorm . When powerful Electric Current s flow through the Earth's Atmosphere from the earth to the clouds, they change the air in their paths into plasma, radiating both sound (thunder) and bright light.]] Electricity (from New Latin ''ēlectricus'', " Amber like") is a general term for a variety of phenomena resulting from the presence and flow of charge. This includes many well-known Physical phenomena such as Lightning , Electromagnetic Field s and Electric Current s, and is put to use in Industrial applications such as Electronics and Electric Power . These related, but distinct, concepts are better identified by more precise terms:
HISTORY OF ELECTRICITY See Also: History of electricity Etymology of electricity Static Electricity produced by rubbing objects against fur was known to the ancient Greeks , Phoenicia ns, Parthia ns and Mesopotamia ns. The Parthians and Mesopotamians may have had some knowledge of Electroplating , based on the discovery of the Baghdad Battery , which resembles a Galvanic Cell . In 1600 the English scientist William Gilbert first used the New Latin word ''electricus'' ("of amber" or "like amber", from ''ηλεκτρον'' {Link without Title} , the Greek word for "amber") to refer to the property of attracting small objects after being rubbed. This soon gave rise to the English words "electric" and "electricity", in Sir Thomas Browne 's '' Pseudodoxia Epidemica '' of 1646. Further work was conducted by Otto Von Guericke , Robert Boyle , Stephen Gray and C. F. Du Fay . In the 18th Century, Benjamin Franklin conducted extensive research in electricity. He had theories on the relationship between lightning and static electricity, including his famous Kite -flying experiment,which was a key attached to a wet string and kite. During a lightning storm a small spark struck his finger showing that lightning is electricity. It sparked the interest of later scientists whose work provided the basis for modern electrical technology. Most notably these include Luigi Galvani (1737–1798), Alessandro Volta (1745-1827), Michael Faraday (1791–1867), André-Marie Ampère (1775–1836), and Georg Simon Ohm (1789-1854). The late 19th and early 20th century produced such giants of electrical engineering as Nikola Tesla , Antonio Meucci , Thomas Edison , George Westinghouse , Werner Von Siemens , Charles Steinmetz , Alexander Graham Bell and William Thomson, 1st Baron Kelvin . ]] Electric potential See Also: Electric potential The indicates the direction and magnitude of the driving force behind Heat Flow . Similarly, there is an electric potential at every point in space, and its Gradient indicates the direction and magnitude of the driving force behind charge movement. Electric current See Also: Current (electricity) ]] An Electric Current is a flow of Electric Charge , and its intensity is measured in Ampere s. Examples of electric currents include metallic conduction, where Electron s flow through a Conductor Or Conductors such as a metal Wire , and Electrolysis , where Ion s (charged Atom s) flow through liquids. The particles themselves often move quite slowly, while the Electric Field that drives them propagates at close to the Speed Of Light . See '' Electrical Conduction '' for more information. Devices that use charge flow principles in materials are called Electronic Devices . A Direct Current (DC) is a unidirectional flow, while an Alternating Current (AC) reverses direction repeatedly. The time average of an alternating current is zero, but its energy capability ( RMS value) is not zero. Ohm's Law is an important relationship describing the behaviour of electric currents, relating them to Voltage . For historical reasons, electric Current is said to flow from the most positive part of a circuit to the most negative part. The electric current thus defined is called '' Conventional Current ''. It is now known that, depending on the conditions, an electric current can consist of a flow of Charged Particle s in either direction, or even in both directions at once. The positive-to-negative convention is widely used to simplify this situation. If another definition is used - for example, "electron current" - it should be explicitly stated. Electric field See Also: Electric field ]] The concept of electric fields was introduced by Michael Faraday . The electrical field force acts between two charges, in the same way that the gravitational force acts between two Mass es. However, the electric field is a little bit different. Gravitational Force depends on the masses of two bodies, whereas electric force depends on the electric charges of two bodies. While gravity can only pull masses together, the electric force can be an attractive ''or'' Repulsive Force . If both charges are of same sign (e.g. both positive), there will be a repulsive force between the two. If the charges are opposite, there will be an attractive force between the two bodies. The magnitude of the force varies inversely with the square of the distance between the two bodies, and is also proportional to the product of the unsigned magnitudes of the two charges. Electric charge See Also: Electric charge Electric charge is a property of certain Subatomic Particle s (e.g., Electron s and Proton s) which interacts with Electromagnetic Fields and causes attractive and repulsive Force s between them. Electric charge is a fundamental conserved property of Matter and can be precisely quantified. It couples to the Electromagnetic Field , one of the four Fundamental Force s of nature. In this sense, the phrase ". SEE ALSO Safety Electrical phenomena in nature
REFERENCES EXTERNAL LINKS
|
|
|