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Even in oceans at 4 km depth, where the pressure is 400 atm, water suffers only a 1.8% decrease in volume. [98] The viscosity of water is about 10 −3 Pa· s or 0.01 poise at 20 °C (68 °F), and the speed of sound in liquid water ranges between 1,400 and 1,540 meters per second (4,600 and 5,100 ft/s) depending on temperature.
Venus is the second planet from the Sun. It is a terrestrial planet and is the closest in mass and size to its orbital neighbour Earth. Venus is notable for having the densest atmosphere of the terrestrial planets, composed mostly of carbon dioxide with a thick, global sulfuric acid cloud cover. At the surface it has a mean temperature of 737 ...
Barcelona ( / ˌbɑːrsəˈloʊnə / ⓘ BAR-sə-LOH-nə, Catalan: [bəɾsəˈlonə] ⓘ, Spanish: [baɾθeˈlona] ⓘ) is a city on the northeastern coast of Spain. It is the capital and largest city of the autonomous community of Catalonia, as well as the second-most populous municipality of Spain. With a population of 1.6 million within city ...
Euro. The euro ( symbol: €; currency code: EUR) is the official currency of 20 of the 27 member states of the European Union. This group of states is officially known as the euro area or, more commonly, the eurozone. The euro is divided into 100 euro cents. [6] [7]
Quantum mechanics is a fundamental theory in physics that describes the behavior of nature at and below the scale of atoms. [2] : 1.1 It is the foundation of all quantum physics, which includes quantum chemistry, quantum field theory, quantum technology, and quantum information science . Quantum mechanics can describe many systems that ...
Coal, oil, and natural gas remain the primary global energy sources even as renewables have begun rapidly increasing. Definition Renewable energy is usually understood as energy harnessed from continuously occurring natural phenomena. The International Energy Agency defines it as "energy derived from natural processes that are replenished at a faster rate than they are consumed".
Hydrogen is a chemical element; it has symbol H and atomic number 1. It is the lightest element and, at standard conditions, is a gas of diatomic molecules with the formula H2, sometimes called dihydrogen, [11] but more commonly called hydrogen gas, molecular hydrogen or simply hydrogen. It is colorless, odorless, tasteless, [12] non-toxic, and ...
