The adiabatic index of a gas, is the ratio of its specific heat capacity at constant pressure (CP) to its specific heat capacity at constant volume (CV). It is denoted by the greek letter γ (gamma) or the greek letter κ (kappa). γ = CP/CV To understand this definition consider the following experiment:  A closed cylinder with a locked piston contains air.The pressure inside is equal to the outside airpressure.  This cylinder is heated.  Since the ...

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Adiabatic process, Adiabatic process - Adiabatic heating and cooling, Adiabatic process - Ideal gas, Adiabatic process - Derivation of formula, Adiabatic process - Graphing adiabats

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Adiabatic heating and cooling are processes that commonly occur due to a change in the pressure of a gas. Adiabatic cooling occurs when the pressure of a gas is suddenly decreased, such as when it expands into a larger volume. This can be easily experienced by compressing the lips and blowing air through them onto the hand. The breath feels cool because of adiabatic cooling: The air expands when it escapes from the mouth and cools. Adiabatic heating occurs when the pressure of a gas is suddenly increased. An example of this is what goes on i ...

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Adiabatic process, Adiabatic process - Adiabatic heating and cooling, Adiabatic process - Ideal gas, Adiabatic process - Derivation of formula, Adiabatic process - Graphing adiabats

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In thermodynamics, an adiabatic process is a process in which no heat is gained or lost in the working fluid. For example, there are no chemical processes taking place in the fluid and there is no heat transfer from the environment. The term "adiabatic" describes things that are impermeable to heat transfer; for example, an adiabatic boundary is a boundary that is impermeable to heat transfer and the system is said to be adiabatically (or thermally) insulated. An insulated wall approximates an adiabatic boundary. Another exampl ...

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Adiabatic process - Adiabatic heating and cooling Adiabatic process - Ideal gas
Adiabatic process - Derivation of formula
Adiabatic process - Graphing adiabats

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The adiabatic lapse rate is the rate of temperature change that occurs in an atmosphere as a function of elevation, assuming that air behaves adiabatically. This term is most commonly used to refer to Earth's atmosphere. The relationship between change in altitude and change in temperature is expressed as a lapse rate. In general, a lapse rate is the rate at which an atmospheric variable (usually temperature) decreases with altitude. It is expressed as the negative ratio of the temperature ...

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Adiabatic lapse rate - Significance in meteorology Adiabatic lapse rate - Related topics

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Adiabatic demagnetization - Paramagnetic salts. The simplest choice of refrigerant is a sample of a paramagnetic salt, such as cerium magnesium nitrate. The active magnetic dipoles in this case are those of the electron shells of the paramagnetic atoms. In a paramagnetic salt ADR, the heat sink is usually provided by a pumped 4He (~1.2 K) or 3He (~0.3 K) cryostat. An easily attainable 1 Tesla magnetic field is generally required for the initial magnetization. The minimum temperature a ...

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Adiabatic demagnetization, Adiabatic demagnetization - Basic technique, Adiabatic demagnetization - Implementations, Adiabatic demagnetization - Paramagnetic salts, Adiabatic demagnetization - Nuclear demagnetization

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The basic operating principle of an ADR is the use of a strong magnetic field to control the entropy of a sample of material, often called the "refrigerant." Magnetic field constrains the orientation of magnetic dipoles in the refrigerant. The stronger the magnetic field, the more aligned the dipoles are, and this corresponds to lower entropy and heat capacity because the material has (effectively) lost some of its internal degrees of freedom. If the refrigerant is kept at a constant temperature through thermal contact with a heat sink (usua ...

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Adiabatic demagnetization, Adiabatic demagnetization - Basic technique, Adiabatic demagnetization - Implementations, Adiabatic demagnetization - Paramagnetic salts, Adiabatic demagnetization - Nuclear demagnetization

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Asbestos-Ceramic (ca 3900-1800 BP) refers to types of pottery manufactured with asbestos and clay with adiabatic behaviour in Finland, Karelia and Northern-Scandinavia. A further vessel-type does not contain any asbestos, but it has insulating properties and is therefore sometimes included under asbestos-ceramic. The most probable origin of this style of ware is the shores of lake Saimaa in Finland which is the only place for richer easily accessible natural deposits of asbestos in its area of distribution. Finds from in ...

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A chiral anomaly is the anomalous nonconservation of a chiral current. In some theories of fermions with a chiral symmetry the quantization may lead to the breaking of this (global) chiral symmetry. In that case, the charge associated with the chiral symmetry is not conserved. A heuristic handwaving way of explaining this is to suppose there is a Dirac sea of fermions and a large (and therefore adiabatic) instanton suddenly appears, and suddenly, the energy levels gradually shift upwards or downwards. This means particles which ...

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Chiral anomaly - An example: baryonic charge non-conservation
Chiral anomaly - Published articles Chiral anomaly - Textbooks

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Kappa can stand for: Κ or κ, the 10th letter of the Greek alphabet: see Kappa (letter). A type of mischievous water imp in Japanese mythology: see Kappa (mythical creature). The adiabatic index of a gas in physics. A work of literature by Ryunosuke Akutagawa (March 1, 1892 - July 24, 1927). A trickster in Hawaiian mythology: see Kappa (Hawaiian mythology). In traditional Finnish measures, a volume measure at market squares. Physically it is a wooden box open at one side, and

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The Born-Oppenheimer approximation, also known as the adiabatic approximation, is a technique used in quantum chemistry and condensed matter physics in order to de-couple the motion of nuclei and electrons (i.e. to separate the variables corresponding to the nuclear and electronic coordinates in the Schrödinger equation associated to the molecular Hamiltonian). It is based upon the fact that typical electronic velocities far exceed those of nuclei. The Born-Oppenheimer approximation is commonly confused with the Born-Oppenh ...

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Born-Oppenheimer approximation - Hand-waving derivation of the approximation Born-Oppenheimer approximation - Beyond the Born-Oppenheimer Approximation

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The air engine is an emission-free piston engine using compressed air as fuel that was invented by Guy Nègre, a French engineer. It uses the expansion of compressed air to drive the pistons in a modified piston engine. Efficiency of operation is gained through the use of environmental heat at normal temperature to warm the otherwise cold expanded air from the storage tank. This non-adiabatic expansion has the potential to greatly increase the efficiency of the machine. The only exhaust gas is cold air (−15 °C), which is als ...

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The mathematical equation for an ideal fluid undergoing an adiabatic process is where P is pressure, V is volume, and CP being the molar specific heat for constant pressure and CV being the molar specific heat for constant volume. α comes from the number of degrees of freedom (3/2 for monotonic gas, 5/2 for diatomic gas, 3 for complex mo ...

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Adiabatic process, Adiabatic process - Adiabatic heating and cooling, Adiabatic process - Ideal gas, Adiabatic process - Derivation of formula, Adiabatic process - Graphing adiabats

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As unsaturated air rises, its temperature drops at the dry adiabatic rate. The dew point also drops, but much more slowly, typically about 2 °C per 1000 m. If unsaturated air rises far enough, eventually its temperature will reach it's dew point, and condensation will begin to form. This altitude is known as the lifting condensation level. The cloud base will typically be at this altitude. The difference between the dry adiabatic lapse rate and the rate at which the dew point drops will be around 8 °C per 1000 m. Given a diff ...

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Adiabatic lapse rate, Adiabatic lapse rate - Significance in meteorology, Adiabatic lapse rate - Related topics

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A cyclic process can be (ideally) constructed on a P-V diagram out of 3 or 4 of these processes: isochoric, isobaric, isothermal, adiabatic. Each process is one of the following: isothermal (at constant temperature, maintained with heat added or removed from a heat source or sink) isobaric (at constant pressure) isometric/isochoric (at constant volume) adiabatic (no heat is added or removed from the working fluid) Some examples are as follows: < ...

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Cyclic process, Cyclic process - Types of Cycles, Cyclic process - Ideal cycle, Cyclic process - Carnot cycle, Cyclic process - Otto cycle, Cyclic process - Stirling cycle, Cyclic process - State Functions and Entropy, Cyclic process - Demonstration, Cyclic process - Conclusion, Cyclic process - Reference

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Assuming perfect combustion conditions, such as an adiabatic (no heat loss) and complete combustion, the adiabatic combustion temperature can be determined. The formula that yields this temperature is based on the first law of thermodynamics and takes note of the fact that the heat of combustion (calculated from the fuel's heating value) is used entirely for warming up fuel and gas (e.g. oxygen or air). In the case of fossil fuels burnt in air, the combustion temperature depends on the heating value the stoichiometric air ratio λ the heat capacity of fuel a ...

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Combustion, Combustion - Rapid combustion, Combustion - Slower combustion, Combustion - Complete combustion, Combustion - Incomplete combustion, Combustion - Chemical equation, Combustion - Combustion phases, Combustion - Combustion temperatures, Combustion - Combustion Analysis

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The Carnot cycle when acting as a heat engine consists of the following steps: Reversible isothermal expansion of the gas at the "hot" temperature, TH( Isothermal heat addition ). During this step (A to B on diagram) the expanding gas causes the piston to do work on the surroundings. The gas expansion is propelled by absorption of heat from the high temperature reservoir. Reversible adiabatic expansion of the gas. For this step (B to C on diagram) we assume the piston and cy ...

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Carnot heat engine, Carnot heat engine - The Carnot cycle, Carnot heat engine - Properties and significance, Carnot heat engine - The temperature-entropy diagram, Carnot heat engine - The Carnot cycle, Carnot heat engine - Carnot's theorem, Carnot heat engine - Efficiency of real heat engines

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A more accurate expression for the speed of sound is where R (287.05 J/(kg·K) for air) is the gas constant for air: the universal gas constant R, which units of J/(mol·K), is divided by the molar mass of air, as is common practice in aerodynamics) κ (kappa) is the adiabatic index (1.402 for air), sometimes noted γ T is the absolute temperature in kelvins. ...

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Speed of sound, Speed of sound - Details, Speed of sound - Speed of sound in air, Speed of sound - Sound in solids, Speed of sound - Experimental methods, Speed of sound - Single-shot timing methods, Speed of sound - Other methods

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Charles' law says "when a gas is compressed temperature is raised". There are three possible relationships between temperature and pressure in a gas undergoing compression: isothermal - gas at final stage of compression is same temperature as at beginning of compression. In this cycle, heat is removed at the same rate as it is added by the work of compression. This is impractical for a working machine. adiabatic - This assumes that there is no heat transfer, into or out of the process, and that all work added is ...

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Gas compressor, Gas compressor - Compressor designs, Gas compressor - Applications, Gas compressor - Temperature, Gas compressor - Staged compression, Gas compressor - Prime movers

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Since compression generates heat, the compressed air is to be cooled between stages making the compression less adiabatic and more isothermal. The inter-stage coolers cause condensation meaning water separators with drain valves are present. The compressor flywheel may drive a cooling fan. For instance in a typical diving compressor, the air is compressed in three stages. If each stage has a compression ratio of 7 to 1, the compressor can out ...

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Gas compressor, Gas compressor - Compressor designs, Gas compressor - Applications, Gas compressor - Temperature, Gas compressor - Staged compression, Gas compressor - Prime movers

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