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1 天前 · The electron ( e− or β− ) is a subatomic particle with a negative one elementary electric charge.[13] Electrons belong to the first generation of the lepton particle family,[14] and are generally thought to be elementary particles because they have no known components or substructure.[1] The electron's mass is approximately 1/1836 that of ...
- stable ( > 6.6×10²⁸ yr)
- J. J. Thomson (1897)
- e−, β−
- −1 e, −1.602176634×10−19 C
2 天前 · Fibonacci sequence. A tiling with squares whose side lengths are successive Fibonacci numbers: 1, 1, 2, 3, 5, 8, 13 and 21. In mathematics, the Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted Fn .
1 天前 · Electrons and a compact nucleus of protons and neutrons. Atoms are the basic particles of the chemical elements. An atom consists of a nucleus of protons and generally neutrons, surrounded by an electromagnetically bound swarm of electrons. The chemical elements are distinguished from each other by the number of protons that are in their atoms.
3 天前 · The Eiffel Tower (/ˈaɪfəl/ EYE-fəl; French: Tour Eiffel [tuʁ ɛfɛl] ⓘ) is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower from 1887 to 1889. Locally nicknamed "La dame de fer" (French for "Iron Lady"), it was constructed as the ...
3 天前 · This is a list of the world's countries and their dependencies by land, water, and total area, ranked by total area. The entries in this list include, but are not limited to, those in the ISO 3166-1 standard, which includes sovereign states and dependent territories. All 193 member states of the United Nations plus the two observer states are ...
1 天前 · Wireless network technologies. In telecommunications, 5G is the fifth-generation technology standard for cellular networks, which cellular phone companies began deploying worldwide in 2019, and is the successor to 4G technology that provides connectivity to most current mobile phones. Like its predecessors, 5G networks are cellular networks, in ...
3 天前 · Worldwide distribution of country calling codes. Regions are coloured by first digit. Country calling codes, country dial-in codes, international subscriber dialing (ISD) codes, or most commonly, telephone country codes are telephone number prefixes for reaching telephone subscribers in foreign countries or areas via international telecommunication networks.
