Blackbody Radiation

Blackbody in physics is an object, which can easily absorb all sorts of radiations easily, especially the electronic radiations. The main qualities of these objects are that they will be opaque and non-reflective. The temperature of these objects is said to dictate the color of these objects. The atoms present in these bodies will bounce accordingly to the temperature. The reason why black bodies will play a major role in physics is the radiations that they are associated with, which play a great role in the formulation of none other than quantum mechanics. It was in the twentieth century; the relation between quantum mechanics and black body radiations was realized.

The other name given to black body radiation is nothing but cavity radiation. The reason why it is also called cavity radiation is that in the laboratories, small holes are found out to be the nearest approximation to large cavities. Since the light, which enters these holes will have to bounce maximum number of times; they will be absorbed to a great extent and thereby, making black bodies as great absorbers of radiations. The qualities like opaqueness and non-reflective properties will help the blackbody to enhance its absorption capabilities. The man Gustav Kirchoff is said to be the one, who introduced the term ‘black body radiation’ and ‘black body’ in the year 1860. He also stated that the spectrum, which is emanated as a result, is only dependant on the cavity temperature. The other particular materials, which will be heated up will never have any influence on the spectrum.

The electromagnetic radiations will be finally emitted when there will be increase in the black body temperature at particular wavelengths and intensities. Usually, the wavelengths will be shorter and the intensities will be higher. There will be of specific colors according to the temperature ranges.

Questions:

• What is a Black Body?
• How are the radiations absorbed by the Black Body?