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Mogul Lamp
A mogul lamp or six way lamp is a floor lamp which has a large center light bulb surrounded by three (or four) smaller bulbs that may be candelabra-style or standard medium-base bulbs, each mounted base-down. This entire setting is typically covered, at least partially, by a large cylindrical (or bell-shaped) fabric shade which is fitted over the reflector bowl, an upturned, white-colored glass, hemispherical diffuser surrounding the center bulb. The top of the lamp is usually designed to sit just above eye-level of an average adult person standing next to it, to avoid unpleasant glare from unshaded bulbs. Etymology The lamp is named after the Great Mogul. Details The bulb socket in the center has a larger diameter (an E39 or E40 mogul base) than a regular E26 or E27 Edison screw light socket, and is typically made of cast porcelain for the higher temperatures. Mogul-base lamps are available for industrial use in larger power ratings (250-1500) and in halogen, mercury ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mogul Lamp
A mogul lamp or six way lamp is a floor lamp which has a large center light bulb surrounded by three (or four) smaller bulbs that may be candelabra-style or standard medium-base bulbs, each mounted base-down. This entire setting is typically covered, at least partially, by a large cylindrical (or bell-shaped) fabric shade which is fitted over the reflector bowl, an upturned, white-colored glass, hemispherical diffuser surrounding the center bulb. The top of the lamp is usually designed to sit just above eye-level of an average adult person standing next to it, to avoid unpleasant glare from unshaded bulbs. Etymology The lamp is named after the Great Mogul. Details The bulb socket in the center has a larger diameter (an E39 or E40 mogul base) than a regular E26 or E27 Edison screw light socket, and is typically made of cast porcelain for the higher temperatures. Mogul-base lamps are available for industrial use in larger power ratings (250-1500) and in halogen, mercury ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury Vapor
A mercury-vapor lamp is a gas-discharge lamp that uses an electric arc through vaporized mercury to produce light. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger soda lime or borosilicate glass bulb. The outer bulb may be clear or coated with a phosphor; in either case, the outer bulb provides thermal insulation, protection from the ultraviolet radiation the light produces, and a convenient mounting for the fused quartz arc tube. Mercury vapor lamps are more energy efficient than incandescent lamps with luminous efficacies of 35 to 55 lumens/watt. Their other advantages are a long bulb lifetime in the range of 24,000 hours and a high intensity, clear white light output. For these reasons, they are used for large area overhead lighting, such as in factories, warehouses, and sports arenas as well as for streetlights. Clear mercury lamps produce a greenish light due to mercury's combination of spectral lines. This is not fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics with the major subdisciplines of number theory, algebra, geometry, and analysis, respectively. There is no general consensus among mathematicians about a common definition for their academic discipline. Most mathematical activity involves the discovery of properties of abstract objects and the use of pure reason to prove them. These objects consist of either abstractions from nature orin modern mathematicsentities that are stipulated to have certain properties, called axioms. A ''proof'' consists of a succession of applications of deductive rules to already established results. These results include previously proved theorems, axioms, andin case of abstraction from naturesome basic properties that are considered true starting points of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Night Light
A nightlight is a small light fixture, usually electrical, placed for comfort or convenience in dark areas or areas that may become dark at certain times, such as at night or during an emergency. Small long-burning candles serving a similar function are referred to as "tealights". Uses and cultures People usually use nightlights for the sense of security which having a light on provides, or to relieve fear of the dark, especially in young children. Nightlights are also useful to the general public by revealing the general layout of a room without requiring a major light to be switched on, for avoiding tripping over stairs, obstacles, or pets, or to mark an emergency exit. Exit signs often use tritium radioluminescence. Homeowners usually place nightlights in bathrooms, kitchens and hallways to avoid turning on the main light fixture, especially late at night, and causing their eyes to adjust to the brighter light. Some frequent travelers carry small nightlights for temporary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-way Bulb
A 3-way lamp, also known as a tri-light, is a lamp that uses a 3-way light bulb to produce three levels of light in a ''low-medium-high'' configuration. A 3-way lamp requires a 3-way bulb and socket, and a 3-way switch. Unlike an incandescent lamp controlled by a dimmer, each of the filaments operates at full voltage, so the color of the light does not change between the three steps of light available. Certain compact fluorescent lamp bulbs are designed to replace 3-way incandescent bulbs, and have an extra contact and circuitry to bring about similar light level. In recent years, LED three way bulbs have become available as well. Lamp bulbs with dual (carbon) filaments were built as early as 1902 to allow adjustable lighting levels. retrieved March 11, 2017 Three-way bulbs [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Power
Electric power is the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second. Standard prefixes apply to watts as with other SI units: thousands, millions and billions of watts are called kilowatts, megawatts and gigawatts respectively. A common misconception is that electric power is bought and sold, but actually electrical energy is bought and sold. For example, electricity is sold to consumers in kilowatt-hours (kilowatts multiplied by hours), because energy is power multiplied by time. Electric power is usually produced by electric generators, but can also be supplied by sources such as electric batteries. It is usually supplied to businesses and homes (as domestic mains electricity) by the electric power industry through an electrical grid. Electric power can be delivered over long distances by transmission lines and used for applications such as motion, light or heat with high efficiency. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-way Lamp
A 3-way lamp, also known as a tri-light, is a lamp that uses a 3-way light bulb to produce three levels of light in a ''low-medium-high'' configuration. A 3-way lamp requires a 3-way bulb and socket, and a 3-way switch. Unlike an incandescent lamp controlled by a dimmer, each of the filaments operates at full voltage, so the color of the light does not change between the three steps of light available. Certain compact fluorescent lamp bulbs are designed to replace 3-way incandescent bulbs, and have an extra contact and circuitry to bring about similar light level. In recent years, LED three way bulbs have become available as well. Lamp bulbs with dual (carbon) filaments were built as early as 1902 to allow adjustable lighting levels. retrieved March 11, 2017 Three-way bulbs [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Fluorescent Bulb
A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incandescent bulbs. The lamps use a tube that is curved or folded to fit into the space of an incandescent bulb, and a compact electronic ballast in the base of the lamp. Compared to general-service incandescent lamps giving the same amount of visible light, CFLs use one-fifth to one-third the electric power, and last eight to fifteen times longer. A CFL has a higher purchase price than an incandescent lamp, but can save over five times its purchase price in electricity costs over the lamp's lifetime. Like all fluorescent lamps, CFLs contain toxic mercury, which complicates their disposal. In many countries, governments have banned the disposal of CFLs together with regular garbage. These countries have established special collection systems ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal-halide Lamp
A metal-halide lamp is an electrical lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides (compounds of metals with bromine or iodine). It is a type of high-intensity discharge (HID) gas discharge lamp. Developed in the 1960s, they are similar to mercury vapor lamps, but contain additional metal halide compounds in the quartz arc tube, which improve the efficiency and color rendition of the light. The most common metal halide compound used is sodium iodide. Once the arc tube reaches its running temperature, the sodium dissociates from the iodine, adding orange and reds to the lamp's spectrum from the sodium D line as the metal ionizes. As a result, metal-halide lamps have high luminous efficacy of around 75–100 lumens per watt, which is about twice that of mercury vapor lights and 3 to 5 times that of incandescent lights and produce an intense white light. Lamp life is 6,000 to 15,000 hours. As one of the most effici ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Vapor Lamp
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. Two varieties of such lamps exist: low pressure and high pressure. Low-pressure sodium lamps are highly efficient electrical light sources, but their yellow light restricts applications to outdoor lighting, such as street lamps, where they are widely used. High-pressure sodium lamps emit a broader spectrum of light than the low-pressure lamps, but they still have poorer color rendering than other types of lamps. Low-pressure sodium lamps only give monochromatic yellow light and so inhibit color vision at night. Single ended self-starting lamps are insulated with a mica disc and contained in a borosilicate glass gas discharge tube (arc tube) and a metal cap. They include the sodium-vapor lamp that is the gas-discharge lamp in street lighting. Development The low-pressure sodium arc discharge lamp was first made practical around 1920 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halogen
The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is known as group 17. The word "halogen" means "salt former" (or "salt maker"). When halogens react with metals, they produce a wide range of salts, including calcium fluoride, sodium chloride (common table salt), silver bromide and potassium iodide. The group of halogens is the only periodic table group that contains elements in three of the main states of matter at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals or salts. The middle halogens—chlorine, bromine, and iodine—are often used as disinfectants. Organobromides are the most important class of flame retardants, while elemental halogens are dangerous and can be toxic. History The fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamp (fixture)
A light fixture (US English), light fitting (UK English), or luminaire is an electrical device containing an electric lamp that provides illumination. All light fixtures have a fixture body and one or more lamps. The lamps may be in sockets for easy replacement—or, in the case of some LED fixtures, hard-wired in place. Fixtures may also have a switch to control the light, either attached to the lamp body or attached to the power cable. Permanent light fixtures, such as dining room chandeliers, may have no switch on the fixture itself, but rely on a wall switch. Fixtures require an electrical connection to a power source, typically AC mains power, but some run on battery power for camping or emergency lights. Permanent lighting fixtures are directly wired. Movable lamps have a plug and cord that plugs into a wall socket. Light fixtures may also have other features, such as reflectors for directing the light, an aperture (with or without a lens), an outer shell or housing fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
