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Cross section of a typical fluorescent lamp with and without a reflector. Some lamps have an internal opaque reflector. Coverage of the reflector ranges from 120° to 310° of the lamp's circumference. Reflector lamps are used when light is only desired to be emitted in a single direction, or when an application requires the maximum amount of ...
A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, to produce ultraviolet and make a phosphor coating in the lamp glow.
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 for lamp alignment and protection, an electrical ballast or power supply, and a shade to diffuse the light or direct it towards a workspace (e.g., a desk lamp).
The first rubber-insulated cables for US building wiring were introduced in 1922 with US patent 1458803, Burley, Harry & Rooney, Henry, "Insulated electric wire", issued 1923-06-12, assigned to Boston Insulated Wire and Cable . These were two or more solid copper electrical wires with rubber insulation, plus woven cotton cloth over each ...
That means arctic air is blasting over the US, while pressure changes and the motion of the polar vortex whip up high winds and create a perfect recipe for wintry weather.
Christmas Eve is not a designated federal holiday. Still, U.S. presidents, including Joe Biden and Donald Trump, have used the holiday to grant a day off to the country's more than 2 million ...
The suffix after the G indicates the pin spread; the G dates to the use of Glass for the original bulbs. GU usually also indicates that the lamp provides a mechanism for physical support by the luminaire: in some cases, each pin has a short section of larger diameter at the end (sometimes described as a "peg" rather than a "pin" [2]); the socket allows the bulb to lock into place by twisting ...
U.S. President-elect Donald Trump said "anything can happen" when asked about the chances of going to war with Iran during his next term in an interview with Time, coinciding with his being named ...