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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.
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 ...
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 ...
Editing display showing MediaWiki markup language. A wiki ( / ˈwɪki / ⓘ WI-kee) is a form of online hypertext publication that is collaboratively edited and managed by its own audience directly through a web browser. A typical wiki contains multiple pages that can either be edited by the public or limited to use within an organization for ...
Linearity. The Schrödinger equation is a linear differential equation, meaning that if two state vectors and are solutions, then so is any linear combination. of the two state vectors where a and b are any complex numbers. [13] : 25 Moreover, the sum can be extended for any number of state vectors.
0 (zero) is a number representing an empty quantity. Adding 0 to any number leaves that number unchanged. In mathematical terminology, 0 is the additive identity of the integers, rational numbers, real numbers, and complex numbers, as well as other algebraic structures. Multiplying any number by 0 has the result 0, and consequently, division ...
Ethnologue (2023) The following languages are listed as having 45 million or more total speakers in the 26th edition of Ethnologue published in 2023. This section does not include entries that Ethnologue identifies as macrolanguages encompassing all their respective varieties, such as Arabic, Lahnda, Persian, Malay, Pashto, and Chinese.
