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A-Z of AVIONICS
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A-Z of AVIONICS
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Re: A-Z of AVIONICS
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Reply #660 on:
24/03/2007 01:44:55 »
J
ohnson ,Lonnie
Super Soaker -
The Super Soaker ® was invented in 1988 under the original name of the "Power Drencher" and a whole new era of power water squirters began. Invented by Lonnie Johnson, an Aerospace Engineer from Los Angeles, California, the Power Drencher was the first water blaster to incorporate air pressure into its design. Three years later in 1991 when Johnson received his patent, the Power Drencher was renamed "Super Soaker" and a nation-wide advertising campaign was launched.
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K
iller lymphocyte-T
http://www.meducator.org/archive/20040223/05_jon02-sm.gif
http://immuneweb.xxmc.edu.cn/pic/T-lymphocyte%20and%20Activated%20Platelets.jpg
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Reply #662 on:
24/03/2007 12:59:09 »
L
aboratory
Michael Faraday, 19th century physicist and chemist, in his lab.
Biochemistry laboratory at the University of Cologne.
Advanced Photon Source linear accelerator at Argonne National Laboratory.
A laboratory (informally, lab) is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories. These notably include:
* the film laboratory or photographic laboratory
* the computer lab
* the medical lab
* the clandestine lab for the production of illegal drugs
Scientific laboratories can be found in schools and universities, in industry, in government or military facilities, and even aboard ships and spacecraft. A laboratory might offer work space for just one to more than thirty researchers depending on its size and purpose.
Characteristics of scientific laboratories
Labs used for scientific research take many forms because of the differing requirements of specialists in the various fields of science. A physics lab might contain a particle accelerator or vacuum chamber, while a metallurgy lab could have apparatus for casting or refining metals or for testing their strength. A chemist or biologist might use a wet laboratory, while a psychologist's or economist's lab might be a room with one-way mirrors and hidden cameras in which to observe behavior. In some laboratories, computers (sometimes supercomputers) are used for either simulations or the analysis of data collected elsewhere. Scientists in other fields will use still other types of laboratories.
Despite the great differences among laboratories, some features are common. The use of workbenches or countertops at which the scientist may choose to either sit or stand is a common way to ensure comfortable working conditions for the researcher, who may spend a large portion of his or her working day in the laboratory. The provision of cabinets for the storage of laboratory equipment is quite common. It is traditional for a scientist to record an experiment's progress in a laboratory notebook, but modern labs almost always contain at least one computer workstation for data collection and analysis.
Lab safety
In some laboratories, conditions are no more dangerous than in any other room. In many labs, though, hazards are present. Laboratory hazards are as varied as the subjects of study in laboratories, and might include poisons; infectious agents; flammable, explosive, or radioactive materials; moving machinery; extreme temperatures; or high voltage. In laboratories where dangerous conditions might exist, safety precautions are important. Rules exist to minimize the individual's risk, and safety equipment is used to protect the lab user from injury or to assist in responding to an emergency.
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Reply #663 on:
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M
ultiple
M
yeloma
http://www.uams.edu/radiology/info/clinical/PET/images/multiple_myeloma.jpg
http://mail.mef.hr/~amusic/slike/slike%20edukon/heme2-2a.jpg
Background:
Multiple myeloma is a debilitating malignancy that is part of a spectrum of diseases ranging from monoclonal gammopathy of unknown significance (MGUS) to plasma cell leukemia. First described in 1848, multiple myeloma is a disease characterized by a
proliferation of malignant plasma cells
and a subsequent overabundance of
monoclonal paraprotein
. An intriguing feature of this disease is that the antibody-forming cells (ie, plasma cells) are malignant and, therefore, may cause unusual manifestations.
Myeloma can be
asymptomatic or insidious
. The disease can cause systemic ailments, including infections and renal failure, and local catastrophes, including pathologic fractures and spinal cord compression. Although patients benefit from treatment (ie, longer life, less pain, fewer complications), currently no cure exists. Recent advances in therapy have helped to lessen the occurrence and severity of adverse effects.
Pathophysiology:
Multiple myeloma can cause a wide variety of problems. The proliferation of plasma cells may interfere with the normal production of blood cells, resulting in leukopenia, anemia, and thrombocytopenia. The cells may cause
soft tissue masses
(plasmacytomas) or
lytic lesions in the skeleton
. Feared complications of this malignancy are
bone pain, hypercalcemia, and spinal cord compression
. The aberrant antibodies that are produced lead to impaired humoral immunity, and patients have a high prevalence of infection, especially with encapsulated organisms. The overproduction of these antibodies may lead to hyperviscosity, amyloidosis, and renal failure.
Frequency:
In the US: Age-adjusted annual incidence is
4.3
cases per 100,000 white men,
3
cases per 100,000 white women,
9.6
cases per 100,000 black men, and
6.7
cases per 100,000 black women.
...
more from e-medicine:
http://www.emedicine.com/med/topic1521.htm
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Reply #664 on:
24/03/2007 15:37:54 »
N
apier John
John Napier 1550 - 1617
John Napier was a Scottish mathematician and inventor. Napier is famous for creating mathematical logarithms, creating the decimal point, and for inventing Napier's Bones, a calculating instrument.
While better known as a mathematician, John Napier was a busy inventor. He proposed several military inventions including: burning mirrors that set enemy ships on fire, special artillery that destroyed everything within a radius of four miles, bulletproof clothing, a crude version of a tank, and a submarine-like device. John Napier invented a hydraulic screw with a revolving axle that lowered water levels in coal pits. Napier also worked on agricultural innovations to improve crops with manures and salt.
As a Mathematician, the highlight of John Napier's life was the creation of logarithms and the decimal notation for fractions.
Sponsored Links
His other mathematical contributions included: a mnemonic for formulas used in solving spherical triangles, two formulas known as Napier's analogies used in solving spherical triangles, and the exponential expressions for trigonometric functions.
In 1621, English mathematician and clergyman, William Oughtred used Napier's logarithms when he invented the slide rule. Oughtred invented the standard rectilinear slide rule and circular slide rule.
Napier's bones were multiplication tables written on strips of wood or bones. The invention was used for multiplying, dividing, and taking square roots and cube roots
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Reply #665 on:
24/03/2007 16:45:38 »
O
ncotic pressure
http://www.life.umd.edu/classroom/bsci440/higgins/side1side2.GIF
Oncotic pressure
From Wikipedia, the free encyclopedia
In blood plasma, the dissolved compounds have an
osmotic pressure
. A small portion of the total osmotic pressure is due to the presence of
large protein molecules
; this is known as the
colloidal osmotic pressure, or oncotic pressure
. Because large plasma proteins can't easily cross through the capillary walls, their effect on the osmotic pressure of the capillary interiors will, to some extent, balance out the tendency for fluid to leak out of the capillaries. In conditions where plasma proteins are reduced, e.g. from being lost in the urine (proteinuria) or from malnutrition, the result of the too low oncotic pressure can be edema – excess fluid buildup in the tissues.
It is represented by the symbol π
Related to hydrostatic pressure, starling equation.
http://en.wikipedia.org/wiki/Oncotic_pressure
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Blaise
P
ascal (1623-1662)
Blaise Pascal is credited with inventing an early calculator.
Blaise Pascal, the French scientist was one of the most reputed mathematician and physicist of his time. He is credited with inventing an early calculator, amazingly advanced for its time. A genuis from a young age, Blaise Pascal composed a treatise on the communication of sounds at the age of twelve, and at the age of sixteen he composed a treatise on conic sections.
The Pascaline
The idea of using machines to solve mathematical problems can be traced at least as far as the early 17th century. Mathematicians who designed and implemented calculators that were capable of addition, subtraction, multiplication, and division included Wilhelm Schickhard, Blaise Pascal, and Gottfried Leibnitz. In 1642, at the age of eighteen Blaise Pascal invented his numerical wheel calculator called the Pascaline to help his father a French tax collector count taxes. The Pascaline had eight movable dials that added up to eight figured long sums and used base ten. When the first dial (one's column) moved ten notches - the second dial moved one notch to represent the ten's column reading of 10 - and when the ten dial moved ten notches the third dial (hundred's column) moved one notch to represent one hundred and so on.
Roulette Machine
Blaise Pascal introduced a very primitive version of the roulette machine in the 17th century. The roulette was a by-product of Blaise Pascal's attempts to invent a perpetual motion machine.
Wrist Watch
The first reported person to actually wear a watch on the wrist was the French mathematician and philosopher, Blaise Pascal. With a piece of string, he attached his pocket watch to his wrist.
Pascal (Pa
)
Unit of atmospheric pressure named in honor of Blaise Pascal, whose experiments greatly increased knowledge of the atmosphere. A pascal is the force of one newton acting on a surface area of one square meter. It is the unit of pressure designated by the International System. l00,OOO Pa= 1000mb 1 bar
Pascal
Blaise Pascal's contribution to computing was recognized by computer scientist Nicklaus Wirth, who in 1972 named his new computer language Pascal (and insisted that it be spelled Pascal, not PASCAL).
Blaise Pascal - Biography
Blaise Pascal was born at Clermont on June 19, 1623, and died at Paris on Aug. 19, 1662. His father, a local judge and tax collector at Clermont, and himself of some scientific reputation, moved to Paris in 1631, partly to prosecute his own scientific studies, partly to carry on the education of his only son, who had already displayed exceptional ability. Blaise Pascal was kept at home in order to ensure his not being overworked, and with the same object it was directed that his education should be at first confined to the study of languages, and should not include any mathematics. This naturally excited the boy's curiosity, and one day, being then twelve years old, he asked in what geometry consisted. His tutor replied that it was the science of constructing exact figures and of determining the proportions between their different parts. Blaise Pascal, stimulated no doubt by the injunction against reading it, gave up his play-time to this new study, and in a few weeks had discovered for himself many properties of figures, and in particular the proposition that the sum of the angles of a triangle is equal to two right angles.
At the age of fourteen Blaise Pascal was admitted to the weekly meetings of Roberval, Mersenne, Mydorge, and other French geometricians; from which, ultimately, the French Academy sprung. At sixteen Blaise Pascal wrote an essay on conic sections; and in 1641, at the age of eighteen, he constructed the first arithmetical machine, an instrument which, eight years later, he further improved. His correspondence with Fermat about this time shews that he was then turning his attention to analytical geometry and physics. He repeated Torricelli's experiments, by which the pressure of the atmosphere could be estimated as a weight, and he confirmed his theory of the cause of barometrical variations by obtaining at the same instant readings at different altitudes on the hill of Puy-de-Dôme.
In 1650, when in the midst of these researches, Blaise Pascal suddenly abandoned his favorite pursuits to study religion, or, as he says in his Pensées, "contemplate the greatness and the misery of man''; and about the same time he persuaded the younger of his two sisters to enter the Port Royal society.
In 1653, Blaise Pascal had to administer his father's estate. He now took up his old life again, and made several experiments on the pressure exerted by gases and liquids; it was also about this period that he invented the arithmetical triangle, and together with Fermat created the calculus of probabilities. He was meditating marriage when an accident again turned the current of his thoughts to a religious life. He was driving a four-in-hand on November 23, 1654, when the horses ran away; the two leaders dashed over the parapet of the bridge at Neuilly, and Blaise Pascal was saved only by the traces breaking. Always somewhat of a mystic, he considered this a special summons to abandon the world. He wrote an account of the accident on a small piece of parchment, which for the rest of his life he wore next to his heart, to perpetually remind him of his covenant; and shortly moved to Port Royal, where he continued to live until his death in 1662. Constitutionally delicate, he had injured his health by his incessant study; from the age of seventeen or eighteen he suffered from insomnia and acute dyspepsia, and at the time of his death was physically worn out.
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Re: A-Z of AVIONICS
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Reply #667 on:
25/03/2007 09:52:25 »
http://en.wikipedia.org/wiki/Quantum_leap
Quantum leap
From Wikipedia, the free encyclopedia
Jump to: navigation, search
This article is about the physical phenomenon. For the television program, see Quantum Leap (TV series).
In physics, a quantum leap or quantum jump is a change of an electron from one energy state to another within an atom. It is discontinuous; the electron jumps from one energy level to another instantaneously. The phenomenon contradicts classical theories, which expect energy levels to be continuous. Quantum leaps are the sole cause of the emission of electromagnetic radiation, including that of light, which occurs in the form of quantized units called photons.
[edit] Vernacular usage
In the vernacular, the term quantum leap has come to mean an abrupt change or "step change", especially an advance or augmentation. The term dates back to early-to-mid-20th century. The vernacular usage usually implies a large and abrupt change, while the term typically refers to a small change in quantum mechanics, often the smallest. The usages agree, however, in that both describe a change that happens all at once, rather than gradually over time. A 'quantum leap in technology' is thus a revolutionary advance, rather than an evolutionary one.
[size=07pt]
( Neily, I know this is not the right place, because I missed it, but WOWWWWWW! That Ferris wheel was beautiful! So Pretty!)
[/size]
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Reply #668 on:
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R
eef (coral)
http://www.biosbcc.net/ocean/marinesci/04benthon/crimg/barrierreef.jpg
http://www.biosbcc.net/ocean/marinesci/04benthon/crimg/cr0763.jpg
http://www.biosbcc.net/ocean/marinesci/04benthon/crimg/cr0530.jpg
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Reply #669 on:
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Henry
S
hrapnel
(1761–1842)
According to Britannica.com: "Shrapnel is a type of antipersonnel projectile named for its inventor, Major-General Henry Shrapnel, an English artillery officer. Shrapnel projectiles contained small shot or spherical bullets, usually of lead, along with an explosive charge to scatter the shot as well as fragments of the shell casing. Henry Shrapnel invented his shrapnel shell for cannons in 1784, which was later adopted by the British army in 1803 for cannons and rifles. Shrapnel was born in 1761 and died in 1842."
This photo (above) depicts two shrapnel balls from a World War I era 75-mm.
shrapnel projectile and a fragment from a World War I era 75-mm. high explosive shell.
The intended destructive effect of the shrapnel projectile against men and animals came from the shrapnel balls. The projectile casing, which merely acted as a carrier for the shrapnel balls, was not designed to fracture or fragment. Some World War I era shrapnel projectiles contained a mixture of two sized balls. The smaller balls, intended for anti-personnel use, constituted approximately ninety per cent of the shrapnel round. The remaining percentage of larger balls were included to disable or kill horses.
The intended destructive effect of high explosive rounds came from the action of the high explosive charge coupled with the fragmentation of the projectile casing. Whereas a shrapnel round was intended to kill or injure people and animals, high explosive rounds were originally designed to damage or destroy inanimate objects such as buildings and field guns.
Historical Background on Shrapnel
Henry ShrapnelOne of the earliest kinds of scatter projectiles was case shot, or canister, used at Constantinople in 1453. The name comes from its case, or can, usually metal, which was filled with scrap, musket balls, or slugs. Somewhat similar, but with larger iron balls and no metal case, was grape shot, so-called from the grape-like appearance of the clustered balls. A stand of grape in the 1700's consisted of a wooden disk at the base of a short wooden rod that served as the core around which the balls stood. The whole assembly was bagged in cloth and reinforced with a net of heavy cord. In later years grape was made by bagging two or three tiers of balls, each tier separated by an iron disk. Grape could disable men at almost 900 yards and was much used during the 1700's. Eventually, it was almost replaced by case shot, which was more effective at shorter ranges (400 to 700 yards). Incidentally, there were 2,000 sacks of grape at the Castillo in 1740, more than any other type projectile.
Spherical case shot was an attempt to carry the effectiveness of grape and canister beyond its previous range, by means of a bursting shell. It was the forerunner of the shrapnel used so much in World War I and was invented by Lt. Henry Shrapnel, of the British Army, in 1784. There had been previous attempts to produce a projectile of this kind, such as the German Zimmerman's "hail shot" of 1573—case shot with a bursting charge and a primitive time fuse, however, Henry Shrapnel's invention was the first air-bursting case shot which, in technical words, "imparted directional velocity" to the bullets it contained. Henry Shrapnel's new shell was first used against the French in 1808, but was not called by its inventor's name until 1852.
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Reply #670 on:
25/03/2007 15:06:50 »
T
oxocara canis
http://www.dpd.cdc.gov/dpdx/images/ParasiteImages/S-Z/Toxocariasis/Toxocara_canis_LifeCycle.gif
http://www.preston.gov.uk/Images/General/Environmental%20Health/Toxocara%20canis%20sexually%20mature%20parasites.gif
http://cal.vet.upenn.edu/dxendopar/images/parasiteimages/ascarids/toxo_egg2.gif
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Reply #671 on:
25/03/2007 23:08:01 »
Star
U
plifting
..........is any of several hypothetical processes by which a highly advanced civilization (at least Kardashev-II) could remove a substantial portion of a star's matter in a controlled manner for other uses. The term appears to have been coined by David Criswell.
Stars already lose a small flow of mass via solar wind, coronal mass ejections, and other natural processes. Over the course of a star's life on the main sequence this loss is usually negligible compared to the star's total mass; only at the end of a star's life when it becomes a red giant or a supernova is a large amount of material ejected. The star lifting techniques that have been proposed would operate by increasing this natural plasma flow and manipulating it with magnetic fields.
Stars have deep gravity wells, so the energy required for such operations is large. For example, lifting solar material from the surface of the Sun to infinity requires 2.1 × 1011 J/kg. This energy could be supplied by the star itself, collected by a Dyson sphere; using only 10% of the Sun's total power output would allow 5.9 × 1021 kilograms of matter to be lifted per year (0.0000003% of the Sun's total mass). The Dyson sphere would need to be designed to allow the lifted material to egress through it.
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Reply #672 on:
25/03/2007 23:17:14 »
V
itamin D3
http://www.axxora.com/files/formula/LKT-C0145.gif
http://www.photomed.de/uploads/pics/vitamin_d3_01.jpg
http://www.mmaonline.net/Publications/MNMed2005/November/Images/sun.gif
http://www.teridanielsbooks.com/States/Florida/children,%20beach,%20sand,.jpg
...and this seems to be 'my' ideal closure for almost any topic!
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Reply #673 on:
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Watt-Hour =
A unit of elecrical energy or work ,equal to one watt, acting for one hour,or 3,600 joules
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X
antine
http://www.benbest.com/health/xanthines.gif
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yttrium-aluminium-garnet(YAG) laser
Yawning
Yaws
Y Chromosome
Yeast
Yellow Fever
Yersinia Pestis
Yolk (deutoplasm)
Yolk Sac (vitelline sac)
yttrium-90
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Z
ollinger-Ellison syndrome
http://health.yahoo.com/media/mayoclinic/images/image_popup/ah6a207_big.jpg
Zollinger-Ellison syndrome
Zollinger-Ellison syndrome is a disorder where increased levels of the hormone
gastrin
are produced, causing the stomach to produce
excess hydrochloric acid
. Often, the cause is a
tumour of the pancreas producing the hormone gastrin
. Gastrin then causes an excessive production of acid which can lead to peptic ulcers.
Gastrin works on stomach parietal cells causing them to secrete more
hydrogen ions
into the stomach lumen. In addition, gastrin acts as a trophic factor for parietal cells, causing parietal cell hyperplasia. Thus, there is an increase in the number of acid secreting cells and each of these cells produces acid at a higher rate. The increase in acidity contributes to the development of peptic ulcers in the stomach and duodenum. High acid levels lead to multiple ulcers in the stomach and small bowel.
Patients with Zollinger-Ellison syndrome may experience
abdominal pain and diarrhea
. The diagnosis is also suspected in patients without symptoms who have severe ulceration of the stomach and small bowel.
Gastrinomas
may occur as single tumors or as multiple, small tumors. About one-half to two-thirds of single gastrinomas are malignant tumors that most commonly spread to the liver and lymph nodes near the pancreas and small bowel. Nearly 25 percent of patients with gastrinomas have multiple tumors as part of a condition called multiple endocrine neoplasia type I (MEN I). MEN I patients have tumors in their pituitary gland and parathyroid glands in addition to tumors of the pancreas.
From
Wikipedia
, the free encyclopedia:
http://en.wikipedia.org/wiki/Zollinger-Ellison_syndrome
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A
rchimedes
Archimedes (287-212 bc), pre-eminent Greek mathematician and inventor, who wrote important works on plane and solid geometry, arithmetic, and mechanics.
Archimedes was born in Syracuse, Sicily, and educated in Alexandria, Egypt. In pure mathematics he anticipated many of the discoveries of modern science, such as the integral calculus, through his studies of the areas and volumes of curved solid figures and the areas of plane figures. He also proved that the volume of a sphere is two-thirds the volume of a cylinder that circumscribes the sphere.
In mechanics, Archimedes defined the principle of the lever and is credited with inventing the compound pulley. During his stay in Egypt he invented the hydraulic screw for raising water from a lower to a higher level. He is best known for discovering the law of hydrostatics, often called Archimedes' principle, which states that a body immersed in fluid loses weight equal to the weight of the amount of fluid it displaces. This discovery is said to have been made as Archimedes stepped into his bath and perceived the displaced water overflowing.
Archimedes spent the major part of his life in Sicily, in and around Syracuse. He did not hold any public office but devoted his entire lifetime to research and experiment. During the Roman conquest of Sicily, however, he placed his gifts at the disposal of the state, and several of his mechanical devices were employed in the defence of Syracuse. Among the war machines attributed to him are the catapult and—perhaps legendary—a mirror system for focusing the Sun's rays on the invaders' boats and igniting them.
After the capture of Syracuse during the Second Punic War, Archimedes was killed by a Roman soldier who found him drawing a mathematical diagram in the sand. It is said that Archimedes was so absorbed in calculation that he offended the intruder merely by remarking, “Do not disturb my diagrams.” Several of his works on mathematics and mechanics survive, including Floating Bodies, The Sand Reckoner, Measurement of the Circle, Spirals, and Sphere and Cylinder. They all exhibit the rigour and imaginativeness of his mathematical thinking.
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Re: A-Z of AVIONICS
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Bethe, Hans
black holes
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Re: A-Z of AVIONICS
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C
apacitor
From Wikipedia, the free encyclopedia
A capacitor is an electrical device that can store energy in the electric field between a pair of closely-spaced conductors (called 'plates'). When voltage is applied to the capacitor, electric charges of equal magnitude, but opposite polarity, build up on each plate.
Capacitors are used in electrical circuits as energy-storage devices. They can also be used to differentiate between high-frequency and low-frequency signals and this makes them useful in electronic filters.
Capacitors are occasionally referred to as condensers. This is now considered an antiquated term.
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