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Author Topic: Are penultimate shells taken into account in Black Body Radiation?  (Read 2256 times)

Offline Anukshan Ghosh

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Before conclusion did Max Planck completely rule out the distribution of energy to ultimate and penultimate shells?At certain temperature the intensity vs λ <wavelength> plot shew erratic results.If one sees the graph one could easily make out that the heat(energy) is evenly distributed among the aspirant atoms to bring about collective good of the atoms.X-RAYS,UVS have high penetration power or can influence the penultimate along with the ultimate shell or the energy gets further distributed,and hence on the graph it shew inclination of the max λ to the right which continued.Hence which brings me to the question-why was the J.C Maxwell wrong in proposing Brightneass ≈ energy? 
« Last Edit: 13/01/2011 11:56:04 by Anukshan Ghosh »


 

Offline Soul Surfer

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Black body radiation only deals with atoms and molecules undergoing elastic collisions where inelastic and spectral absorption or emission is concerned it is no longer a black body.
 

Offline Anukshan Ghosh

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Black body radiation only deals with atoms and molecules undergoing elastic collisions where inelastic and spectral absorption or emission is concerned it is no longer a black body.
huh... spectral absorptions within the black body cannot happen is that what you mean????
 

Offline Soul Surfer

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No.  Spectral emissions and absorptions can happen with any sort of material under many conditions.  "black body radiation" specifically does not concern itself with this.  Black body radiation is specifically the frequency range and intensity of electromagnetic radiation radiated by all objects as a result of their temperature that is the thermal agitation of their atoms and molecules.  For solids and liquids the efficiency of radiating this radiation is dependant on the nature of their surfaces.  Shiny polished reflecting surfaces radiate least and (optically) matt black surfaces radiate most at optical frequencies.  This idealised black surface is called a "black body" and it requires very careful design to create one.
« Last Edit: 20/01/2011 08:56:47 by Soul Surfer »
 

Offline Anukshan Ghosh

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and hence lets take what you said to a level further and think what happens within the body 
 

Offline Soul Surfer

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My statement cannot be taken further.  A black body is a theoretical construct relating to the behaviour of matter generally under certain conditions.  It has a solid theoretical base and has been proved adequately by experiments and is useful in certain kinds of radiation modelling.  The absorption and emission of spectral lines by bodies is a totally different area of physics and has no relationship to it except that in creating an experimental black body to test, spectral absorption an emission has to be avoided.

A classical experimental black body at optical and infra red frequencies consists of a sphere of metal roughened and blackened on the inside it has a medium sized hole in its side through which the inside may be seen.  It is mounted in a temperature controlled furnace and allowed to stabilise at a known temperature.  The radiation inside the sphere reaches equilibrium. The hole in the sphere is the "black body"!   Just the hole in the sphere is examined with a radiometer and/or a spectrometer to determine the black body radiation.  This has been used to confirm Stefans fourth power law of total radiation energy and Planck's law concerning the spectral distribution of this energy.
 

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