A thermodynamic state is the macroscopic condition of a thermodynamic system as described by its particular thermodynamic parameters. The state of any thermodynamic system can be described by a set of thermodynamic parameters, such as temperature, pressure, density, composition, independently of its surroundings or history.
The parameters required to specify the state depend on the characteristics of the system. There is an optimal ensemble of parameters that uniquely specify the state, and all other parameters can be derived from these. The "state postulate" says that the state of a simple compressible system is completely specified by two independent, intensive properties.
Thermal physics
Thermal physics is the combined study of thermodynamics, statistical mechanics, and kinetic theory. This umbrella-subject is typically designed for physics students and functions to provide a general introduction to each of three core heat-related subjects. Other authors, however, define thermal physics loosely as a summation of only thermodynamics and statistical mechanics.
Thermal physics, generally speaking, is the study of the statistical nature of physical systems from an energetic perspective. Starting with the basics of heat and temperature, thermal physics analyzes the first law of thermodynamics and second law of thermodynamics from the statistical perspective, in terms of the number of microstates corresponding to a given macrostate. In addition, the concept of entropy is studied via quantum theory.
A central topic in thermal physics is the canonical probability distribution. The electromagnetic nature of photons and phonons are studied which show that the oscillations of electromagnetic fields and of crystal lattices have much in common. Waves form a basis for both, provided one incorporates quantum theory.
Other topics studied in thermal physics include: chemical potential, the quantum nature of an ideal gas, i.e. in terms of fermions and bosons, Bose-Einstein condensation, Gibbs free energy, Helmholtz free energy, chemical equilibrium, phase equilibrium, the equipartition theorem, entropy at absolute zero, and transport processes as mean free path, viscosity, and conduction.
There are two types of thermodynamic instruments, the meter and the reservoir. A thermodynamic meter is any device which measures any parameter of a thermodynamic system. In some cases, the thermodynamic parameter is actually defined in terms of an idealized measuring instrument. For example, the zeroth law states that if two bodies are in thermodynamic equilibrium with a third body, they are also in thermodynamic equilibrium with each other. This principle, as noted by James Maxwell in 1872, asserts that it is possible to measure temperature. An idealized thermometer is a sample of an ideal gas at constant pressure.
A thermodynamic reservoir is a system which is so large that it does not appreciably alter its state parameters when brought into contact with the test system.
It is important that these two types of instruments are distinct. A meter does not perform its task accurately if it behaves like a reservoir of the state variable it is trying to measure. If, for example, a thermometer, were to act as a temperature reservoir it would alter the temperature of the system being measured, and the reading would be incorrect. Ideal meters have no effect on the state variables of the system they are measuring.
Statistical mechanics
Statistical mechanics is the application of probability theory, which includes mathematical tools for dealing with large populations, to the field of mechanics, which is concerned with the motion of particles or objects when subjected to a force.
It provides a framework for relating the microscopic properties of individual atoms and molecules to the macroscopic or bulk properties of materials that can be observed in everyday life, therefore explaining thermodynamics as a natural result of statistics and mechanics (classical and quantum) at the microscopic level. In particular, it can be used to calculate the thermodynamic properties of bulk materials from the spectroscopic data of individual molecules.
This ability to make macroscopic predictions based on microscopic properties is the main asset of statistical mechanics over thermodynamics. Both theories are governed by the second law of thermodynamics through the medium of entropy. However, entropy in thermodynamics can only be known empirically, whereas in statistical mechanics, it is a function of the distribution of the system on its micro-states.
Kinetic theory
Kinetic theory or "kinetic theory of gases" attempts to explain overall properties of gases, such as pressure, temperature, or volume, by considering their molecular composition and motion. The theory basically states that pressure is not caused by molecules pushing each other away, like earlier scientists thought. Instead, pressure is caused by the molecules colliding with each other and their container. Kinetic theory is also known as "kinetic-molecular theory" or "collision theory".
There are three main components to kinetic theory:
The main postulate of this theory are--
1.The particles attract each other with a force. This force is called cohesive force if the particles are of same kind and adhesive force when particles are of different kinds.
2. All matter is composed of small particles called molecules. (Atoms or ions as the situation demands).
3. The particles are in a state of unending motion (continuous motion) and as such have kinetic energy.
4. with the supply of heat energy (thermal energy) to matter, the kinetic energy of a particle increase, i.e., they start moving more vigorously. Reverse happens if the matter is cooled.i.e., heat energy is taken out of it.
5. The force of attraction between the particles decreases, if the distance between them increases and vice versa.
Last updated Sat,16 May 2020
9:00 pm
By Rachit Vishwakarma
Frik
Frik was an Armenian poet who lived in the 13th and 14th centuries, at the time of Mongolian control over Armenia.
Mongolian
Mongolian might mean:
Yeghishe Charents
Yeghishe Charents (born Yeghishe Soghomonian, ) (13 March 1897, Kars - 29 November 1937, Yerevan) was an Armenian poet killed in Stalin's purges.
From 1904 to 1912 Yeghishe Soghomonian he was at school in Kars. Amid the upheavals of the First World War and the Armenian Genocide in the Ottoman Empire, he volunteered in 1915 for the Caucasian Front. In 1917-1918 he was in Karin Erzurum during the bitter fighting. Some of his experiences would later appear in his poetry.
Yeghishe Charents (Soghomonian), one of the nation's favourite poets - a famous philanderer who apparently sought the USSR Kremlin's favours - produced a now famous poem called "The Message". Its praise of Uncle Joe might grind the average set of teeth down to the gum; it included the following: "A new light shone on the world... It is only this sunlight/Which for centuries will stay alive." And more of the same.
Undiscovered by the USSR Kremlin's censors for many months, however, Charents (1897 - 1937) had used the first letter of each line to frame a quite different "message", which read: "O Armenian people, your only salvation is in the power of your unity." Whoops! Like the distant Mount Ararat, it was a brave, hopeless symbol, as doomed as it was impressive. Yeghishe Charents was "disappeared" by the NKVD (KGB) in 1937 after being denounced by the architect Alexsandr Tamanyan - now hard at work building Yerevan's new Stalinist opera house - the moment Yeghishe Charents' schoolboy prank was spotted. Then Alexsandr Tamanyan fell from the roof of his still unfinished opera house, and even today Armenians - with their Arab-like desire to believe in "заговор" the plot - ask the obvious questions.
"Three songs to the sad and pale girl", poems (1914)
"Blue-eyed Homeland", poem (1915)
"Soma", poem (1918) Yerevan
"Charents-Name", poem (1922)
"Uncle Lenin", poem (1924)