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  1. Lightning. Atmospheric noise is radio noise caused by natural atmospheric processes, primarily lightning discharges in thunderstorms. It is mainly caused by cloud-to-ground flashes as the current is much stronger than that of cloud-to-cloud flashes. [citation needed] On a worldwide scale, 3.5 million lightning flashes occur daily.

  2. en.wikipedia.org › wiki › Radio_noiseRadio noise - Wikipedia

    Radio noise. In radio reception, radio noise (commonly referred to as radio static) is unwanted random radio frequency electrical signals, fluctuating voltages, always present in a radio receiver in addition to the desired radio signal. Radio noise near in frequency to the radio signal being received (in the receiver's passband) interferes with ...

  3. The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. At 20 °C (68 °F), the speed of sound in air is about 343 m/s (1,125 ft/s; 1,235 km/h; 767 mph; 667 kn ), or 1 km in 2.91 s or one mile in 4.69 s. It depends strongly on temperature as well as the medium through which a ...

  4. en.wikipedia.org › wiki › 11 - Wikipedia

    1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of unit length is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest ...

  5. "The Sound of Silence" (originally "The Sounds of Silence") is a song by the American folk rock duo Simon & Garfunkel, written by Paul Simon. The duo's studio audition of the song led to a record deal with Columbia Records, and the original acoustic version was recorded in March 1964 at Columbia's 7th Avenue Recording Studios in New York City for their debut album, Wednesday Morning, 3 A.M ...

  6. Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for voice calls for the delivery of voice communication sessions over Internet Protocol (IP) networks, such as the Internet. The broader terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of voice and other communications services ...

  7. Four UN members (Cuba, Liechtenstein, Monaco and North Korea) do not belong to the IMF hence their economies are not ranked below. Kosovo, despite not being a member of the United Nations, is a member of IMF. Taiwan is not a IMF member but it is still listed in the official IMF indices. Several leading GDP-per-capita (nominal) jurisdictions may ...

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