Search results
Results from the WOW.Com Content Network
the process of heat or phonon emission by charge carriers in a solar cell, after a photon that exceeds the semiconductor band gap energy is absorbed. [3] The hypothesis, foundational to most introductory textbooks treating quantum statistical mechanics, [4] assumes that systems go to thermal equilibrium (thermalisation). The process of ...
Development of a thermal equilibrium in a closed system over time through a heat flow that levels out temperature differences. Two physical systems are in thermal equilibrium if there is no net flow of thermal energy between them when they are connected by a path permeable to heat. Thermal equilibrium obeys the zeroth law of thermodynamics. A ...
The zeroth law of thermodynamics defines thermal equilibrium and forms a basis for the definition of temperature: if two systems are each in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
A central aim in equilibrium thermodynamics is: given a system in a well-defined initial equilibrium state, and given its surroundings, and given its constitutive walls, to calculate what will be the final equilibrium state of the system after a specified thermodynamic operation has changed its walls or surroundings.
Thus, the two systems are in thermal equilibrium with each other, or they are in mutual equilibrium. Another consequence of equivalence is that thermal equilibrium is described as a transitive relation: [7]: 56 [10] If A is in thermal equilibrium with B and if B is in thermal equilibrium with C, then A is in thermal equilibrium with C.
The above derivation uses the first and second laws of thermodynamics. The first law of thermodynamics is essentially a definition of heat, i.e. heat is the change in the internal energy of a system that is not caused by a change of the external parameters of the system.
Thermal energy in equilibrium at a given temperature already represents the maximal evening-out of energy between all possible states [4] because it is not entirely convertible to a "useful" form, i.e. one that can do more than just affect temperature.
Thermal equilibrium is achieved when two systems in thermal contact with each other cease to have a net exchange of energy. It follows that if two systems are in thermal equilibrium, then their temperatures are the same. [64] Thermal equilibrium occurs when a system's macroscopic thermal observables