wha is the cavity radiator ?

Question

if anybody have essay about the cavity then please send it to me? or reply me if you have any detail information thank you

Answer 1

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Answer 2

hope this helps


The Historical Prelude

The uncovering of the existence of the ZPE all started in the late 19th century when experiments were conducted with a special cavity radiator known as a black-body. A small hole in an opaque cavity at any given temperature is an emitter of radiation, just as a perfectly black body would be at that temperature. As a consequence, radiation from such a source is called black-body radiation. In 1893, Wilhelm Wien empirically derived a formula describing the distribution of radiant energy density (the energy per unit volume) with wavelength, but the formula deviated a little from the experimental results at long wavelengths2. In 1899, Otto Lummer and Ernst Pringsheim conducted accurate experiments with a cavity radiator over a range of temperatures to determine if the discrepancy was real3-4. The data indicated that Wien’s formula was indeed slightly deficient at long wavelengths. This small deviation was confirmed by similar experiments done by Ferdinand Kurlbaum and Heinrich Rubens. In 1900 Lord Rayleigh and James Jeans theoretically derived a relationship from classical physics in a way that should have been able to describe the experimental results. Instead the graph of their equation climbed dramatically at short wavelengths resulting in what was called the “ultraviolet catastrophe”. This presented a crisis. It indicated that classical theory seemed to be unable to account for some important experimental observations.

However, in 1901 Max Planck was successful in deriving a mathematical expression that fitted the most recent experimental curves for the radiation emanating from a black body. This mathematical formulation overcame the so-called “ultraviolet catastrophe” at short wavelengths, and the lesser problems with Wien’s formula at long wavelengths. Planck achieved this by hypothesizing that the energy states of point particle oscillators came in discrete units rather than being continuous5. That is to say, radiation is not emitted in continuous amounts but in discrete bundles of energy, which are described by the product of the new constant ‘h’, and the frequency, ‘f’, of the radiation6. As Kuhn has pointed out, Planck remained skeptical of the physical significance of his mathematical assumption and his constant ‘h’ for over a decade7. At best, Planck thought it probably only applied to oscillators and their emitted radiation, and therefore only amounted to a slight modification of Maxwell’s theory of radiation.

Answer 3

It's a warming device for your teeth.