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The Debye model is a solid-state equivalent of Planck's law of black body radiation, which treats electromagnetic radiation as a photon gas confined in a vacuum space. Correspondingly, the Debye model treats atomic vibrations as phonons confined in the solid's volume. Most of the calculation steps are identical, as both are examples of a ...
A temperature coefficient describes the relative change of a physical property that is associated with a given change in temperature. For a property R that changes when the temperature changes by dT, the temperature coefficient α is defined by the following equation: Here α has the dimension of an inverse temperature and can be expressed e.g ...
Quantity (common name/s) (Common) symbol/s Defining equation SI unit Dimension Temperature gradient: No standard symbol K⋅m −1: ΘL −1: Thermal conduction rate, thermal current, thermal/heat flux, thermal power transfer
Thermodynamic temperature is a quantity defined in thermodynamics as distinct from kinetic theory or statistical mechanics.. Historically, thermodynamic temperature was defined by Lord Kelvin in terms of a macroscopic relation between thermodynamic work and heat transfer as defined in thermodynamics, but the kelvin was redefined by international agreement in 2019 in terms of phenomena that are ...
Temperature gradient. A temperature gradient is a physical quantity that describes in which direction and at what rate the temperature changes the most rapidly around a particular location. The temperature spatial gradient is a vector quantity with dimension of temperature difference per unit length. The SI unit is kelvin per meter (K/m).
Spontaneous magnetization. Spontaneous magnetization is the appearance of an ordered spin state ( magnetization) at zero applied magnetic field in a ferromagnetic or ferrimagnetic material below a critical point called the Curie temperature or TC .
The Gibbs–Helmholtz equation is a thermodynamic equation used to calculate changes in the Gibbs free energy of a system as a function of temperature. It was originally presented in an 1882 paper entitled " Die Thermodynamik chemischer Vorgänge " by Hermann von Helmholtz. It describes how the Gibbs free energy, which was presented originally ...
The law was actually the last of the laws to be formulated. First law of thermodynamics. d U = δ Q − δ W {\displaystyle dU=\delta Q-\delta W} where. d U {\displaystyle dU} is the infinitesimal increase in internal energy of the system, δ Q {\displaystyle \delta Q} is the infinitesimal heat flow into the system, and.