In meteorology, an anticyclone (i.e. opposite to a cyclone) is a weather phenomenon in which there is a descending movement of the air and a relative increase in barometric pressure over the part of the earth's surface affected by it. At the surface the air tends to flow outwards in all directions from the central area of high pressure, and is deflected on account of the earth's rotation (see Ferrel's law) so as to give a spiral movement. In the northern hemisphere an anticyclone rotates in the clockwise direction, while ...
Gravity is a force of attraction that acts between bodies that have mass. It is a physical phenomenon of fundamental importance, profoundly affecting the workings of the world around us and the universe beyond. Most familiarly, it is the gravitational attraction of the earth that endows objects with weight and causes them to fall to the ground when dropped. In fact, gravity is also the reason for the very existence of the earth, the sun and other celestial bodies; without it matter would not have coalesced into these bodies and ...
Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. The capacitance is usually defined as the total electric charge placed on the object divided by the potential of the object:
or, according to Gauss's law, the capacitance can be expressed as the electric flux per volt
where
C is the capacitance in farads
Q is the charge in coulombs
...
A calorie is a unit of measurement for energy. In most fields, it has been replaced by the joule, the SI unit of energy. However, it remains in common use for the amount of energy obtained from food. Many different definitions for the calorie have emerged during the 19th and 20th century. They fall into two classes:
The small calorie or gram calorie is the energy needed to increase the temperature of 1 g of water by 1 °C. This unit of energy is equivalent to about 4.185 J.
The large c ...
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SI units were used where possible. Unless otherwise stated, standard conditions were used.
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Calcium oxide (CaO), commonly known as lime, quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic and alkaline crystalline solid. As a commercial product lime often also contains magnesium oxide, silicon oxide an ...
General
Physical properties
SI units were used where possible. Unless otherwise stated, standard conditions were used.
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Calcium fluoride (CaF2) is an insoluble ionic compound of calcium and fluorine. It occurs naturally as the mineral fluorite (also called fluorspar), and it is the source of most of the world's fluorine. It reacts with concentrated sulfuric acid to produce hydrogen fluoride:
CaF2(s) + H2
A capacitor is a device that stores energy in the electric field created between a pair of conductors on which equal but opposite electric charges have been placed. A capacitor is occasionally referred to using the older term condenser.
Capacitor - History.
In circa 600 BC, Thales of Miletus recorded that the Ancient Greeks could generate sparks by rubbing balls of amber on spindles. This is the triboelectric effect, the mechanical separation of charge in a dielectric. This effect is th ...
Centi can also stand for Centro Internacional de Teoterapia Integral (Integrated God-centered Therapy International Center).
Centi (symbol c) is a SI prefix in the SI system of units denoting a factor of 10-2, or 1/100.
Adopted in 1795, the prefix comes from the Latin centum, meaning hundred.
See also.
SI prefix
Category: SI prefixes
...
There exist several unit prefixes used like the SI prefixes, but that are not part of the SI system.
Some of these were never part of any actual system of measurement. A few were proposals that were rejected. None are in common use, and many of the powers of ten they represent are already taken by SI prefixes.
One such prefix is bronto, used in the fake term brontobyte. References on the World Wide Web suggest meanings of the bronto prefix to be variously any of 1015, 1021, 1024Including:
In radio communications, characteristic impedance (acoustic impedance or sound impedance) of a uniform transmission line is the impedance of a circuit that, when connected to the output terminals of a line of arbitrary length, causes the line to appear infinitely long. This is sometimes called surge impedance. The SI unit of characteristic impedance is the ohm.
Characteristic impedance - Description.
A uniform line terminated in its characteristic impedance will have no standing waves, no re ...
Zepto (symbol z) is a prefix in the SI system of units denoting a factor of 10-21.
Adopted in 1991, it comes from the French sept or Latin septem, meaning seven, since it is equal to 1/10007.
See also.
SI prefix
Category: SI prefixes
...
Zetta (symbol Z) is a SI prefix in the SI (system of units) denoting 1021 or 1 000 000 000 000 000 000 000.
Adopted in 1991, it comes from the Latin septem, meaning seven, because it is equal to 10007.
A prefix of the same value, Hepa, was informally introduced a few years before the promulgation of Zetta. It was formed from the Greek ἑπτά, (hepta), also meaning seven. It never received official ...
The centimetre-gram-second system (CGS) is a system of physical units. It is always the same for mechanical units, but there are several variants of electric additions.
The system goes back to a proposal made in 1832 by the German mathematician Carl Friedrich Gauss and was in 1874 extended by the British physicists James Clerk Maxwell and William Thomson with a set of electromagnetic units. The sizes (order of magnitude) of many CGS units turned out to be inconvenient for practical purposes, therefore the CGS system neve ...
The General Conference on Weights and Measures is the English name of the Conférence générale des poids et mesures (CGPM, never GCWM). It is one of the three organizations established to maintain the International System of Units (SI) under the terms of the Convention du Mètre (Metre Convention) of 1875. It meets in Paris every four to six years. In 2002 the CGPM represented 51 member states and ten further associ ...
SI units were used where possible. Unless otherwise stated, standard conditions were used.
Disclaimer and references
Sodium bicarbonate (NaHCO3), or sodium hydrogen carbonate, also known as baking soda and bicarbonate of soda, is a soluble white anhydrous or crystalline chemical compound, with a slight alkaline taste resembling that of sodium carbonate. It is foun ...
The bar (symbol bar) and the millibar (symbol mbar, also mb) are units of pressure. They are not SI units, but accepted (although discouraged) for use with the SI. The bar is still widely used in descriptions of pressure because it is about the same as atmospheric pressure.
Bar unit - Definition.
The bar and millibar are defined as:
1 bar = 100 000 pascals (Pa) = 1 000 000 dynes/square centimetre
1 mbar = 0.001 bar = 100 Pa = 1 000 dyn/cm2
Including:
The British thermal unit (BTU or Btu) is a unit of energy still used in the United States. It is also still occasionally encountered in the UK, in the context of older heating and cooling systems. In most other areas, it has been replaced by the SI unit of energy, the joule (J).
A Btu is defined as the amount of heat required to raise the temperature of one pound avoirdupois of water by one degree Fahrenheit. As is the case with the calorie, several different definitions of the Btu exist, which are based on dif ...
Avogadro's number, also called Avogadro's Constant (NA) is a large constant used in chemistry and physics. Avogadro's number is formally defined as the number of carbon-12 atoms in 12 grams (0.012 kg) of carbon-12, which is approximately 6.023 × 1023. Historically, carbon-12 was chosen as the reference substance because its atomic mass could be measured particularly accurately.
A mole is defined as Avogadro's number of particles of any kind of substance (atoms, ions, molecul ...
The astronomical unit (AU or au or a.u. or sometimes ua) is a unit of distance, approximately equal to the mean distance between Earth and Sun. The currently accepted value of the AU is 149 597 870 691 ± 30 metres (about 150 million kilometres or 93 million miles).
The symbol "ua" is recommended by the Bureau International des Poids et Mesures [1], but in the United States and other anglophone countries the reverse usage is more common. The International Astronomical Union recommends "au" [2] and in ...
An atomic clock is a type of clock that uses an atomic resonance frequency standard as its counter. Early atomic clocks were masers with attached equipment. Today's best atomic frequency standards (or clocks) are based on more advanced physics involving cold atoms and atomic fountains. National standards agencies maintain an accuracy of 10-9 seconds per day, and a precision equal to the frequency of the radio transmitter pumping the maser. The clocks maintain a continuous and stable time scale, International Atomic Time (TA ...
