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koustav
- 29
- 4
derivation of wiens displacement law and wiens distribution law from thermodynamic principle.but not from Plancks law
vanhees71 said:This gives the obviously wrong result because of the well-known Rayleigh-Jeans UV catastrophe.
The answer is that we have to consider quantum theory, and this adds the additional universal quantity ##\hbar## of dimension erg s to the game.
vanhees71 said:So there seems to be no way to get the correct Planck spectrum without quantum theory.
Wien's displacement law, of course, holds for both Wien's and Planck's spectrum.
Wiens Displacement and Distribution Laws are important principles in thermodynamics that describe the relationship between the temperature of a body and the wavelength at which it emits the most radiation. These laws are essential for understanding the behavior of thermal radiation and are widely used in various fields of science and engineering.
Wiens Displacement and Distribution Laws can be derived from the principles of thermodynamics, specifically the laws of blackbody radiation. This involves applying the fundamental concepts of energy conservation and entropy to the behavior of thermal radiation.
The mathematical formula for Wiens Displacement Law is λmax = b/T, where λmax is the wavelength of the peak emission, b is a constant known as Wien's displacement constant, and T is the temperature of the body in Kelvin.
Wiens Distribution Law states that the amount of radiation emitted by a body at a given wavelength is proportional to the wavelength to the fifth power multiplied by the exponential of -c/λT, where c is the speed of light and T is the temperature of the body. This means that as the temperature increases, the peak of the distribution shifts to shorter wavelengths and the amount of radiation at all wavelengths increases.
Wiens Displacement and Distribution Laws were originally derived for blackbodies, which are idealized objects that absorb and emit all radiation that falls on them. These laws describe the unique behavior of blackbodies and are used to approximate the behavior of real objects that emit thermal radiation, such as stars and planets.