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  • Microwave


    A telecommunications tower with a variety of dish antennas for microwave relay links on Frazier Peak, Ventura County, California. The apertures of the dishes are covered by plastic sheets (radomes) to keep out moisture. The atmospheric attenuation of microwaves and far infrared radiation in dry air with a precipitable water vapor level of 0.001 mm. The downward spikes in the graph correspond to frequencies at which microwaves are absorbed more strongly. This graph includes a range of frequencies from 0 to 1 THz; the microwaves are the subset in the range between 0.3 and 300 gigahertz.Microwaves are a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter; with frequencies between and . Different sources define different frequency ranges as microwaves; the above broad definition includes both UHF and EHF (millimeter wave) bands. A more common definition in radio engineering is the range between 1 and 100 GHz (wavelengths between 0.3 m and 3 mm). In all cases, microwaves include the entire SHF band (3 to 30 GHz, or 10 to 1 cm) at minimum. Frequencies in the microwave range are often referred to by their IEEE radar band designations: S, C, X, Ku, K, or Ka band, or by similar NATO or EU designations. The prefix ' in microwave is not meant to suggest a wavelength in the micrometer range. Rather, it indicates that microwaves are "small" (having shorter wavelengths), compared to the radio waves used prior to microwave technology. The boundaries between far infrared, terahertz radiation, microwaves, and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study. Microwaves travel by line-of-sight; unlike lower frequency radio waves they do not diffract around hills, follow the earth's surface as ground waves, or reflect from the ionosphere, so terrestrial microwave communication links are limited by the visual horizon to about 40 miles (64 km). At the high end of the band they are absorbed by gases in the atmosphere, limiting practical communication distances to around a kilometer. Microwaves are widely used in modern technology, for example in point-to-point communication links, wireless networks, microwave radio relay networks, radar, satellite and spacecraft communication, medical diathermy and cancer treatment, remote sensing, radio astronomy, particle accelerators, spectroscopy, industrial heating, collision avoidance systems, garage door openers and keyless entry systems, and for cooking food in microwave ovens.

  • Small appliance


    Small appliances in a kitchen: a food processor, a waffle iron, a coffee maker, and an electric kettle filaments of a modern 2-slice toaster A small appliance, small domestic appliance, or small electrics are portable or semi-portable machines, generally used on table-tops, counter-tops, or other platforms, to accomplish a household task. Examples include microwave ovens, toasters, humidifiers, and coffeemakers. They contrast with major appliances (British "white goods"), such as the refrigerator and washing machine, which cannot be easily moved and are generally placed on the floor. Small appliances also contrast with consumer electronics (British "brown goods") which are for leisure and entertainment rather than purely practical tasks.

  • Kitchenette


    A kitchenette is a small cooking area, which usually has a fridge and a microwave, but may have other appliances. In some motel and hotel rooms, small apartments, college dormitories, or office buildings, a kitchenette usually consists of a small refrigerator, a microwave oven or hotplate, and, less frequently, a sink. New York City building code defines a kitchenette as a kitchen of less than 7.4 m2 (80 ft2) of floor space. Example of kitchenette located in a small studio apartment of Sherbrooke, Quebec, Canada.

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