Matter, electromagnetic radiation interaction with

In 1900 Max Planck proposed a solution to the problem of black-body radiation described above. He suggested that when electromagnetic radiation interacts with matter, energy can only be absorbed or emitted in certain discrete amounts, called quanta. Planck s theory will not be described here, as it is highly technical. In any case, Planck s proposal was timid compared with the theory that followed. He supposed that quanta were only important in absorption and emission of radiation, but that otherwise the wave theory did not need to be modified. It was Einstein who took a more radical step in 1905 (the year in which he published his first paper on the theory of relativity and on several other unrelated topics). Einstein s analysis of the photoelectric effect is crucial, and has led to a complete change in the way we think of light and other radiation. 

When electromagnetic radiation interacts with matter it causes the electron density in the material to oscillate at the same frequency as the incident light. Since the interaction of light and matter is a time-resolved process involving many photons, it should not be a surprise that the oscillation produced by... 

Very detailed information about structure is obtained from investigations in which electromagnetic radiation interacts with matter. An important area of study, known as spectroscopy, is concerned mainly with the extent to which substances absorb radiation at various wavelengths. The information obtained through spectroscopy has contributed greatly to our understanding of chemical structure and is particularly important in biology. 

There are three ways in which ionizing (electromagnetic) radiation interacts with matter, viz. 

How does Electromagnetic Radiation interact with Matter ... 

Most of our knowledge about the structure of atoms and molecules is based on spectroscopic investigations. Thus spectroscopy has made an outstanding contribution to the present state of atomic and molecular physics, to chemistry, and to molecular biology. Information on molecular structure and on the interaction of molecules with their surroundings may be derived in various ways from the absorption or emission spectra generated when electromagnetic radiation interacts with matter. 

Understanding how light (radiant energy, or electromagnetic radiation) interacts with matter provides insights into the behavior of electrons in atoms. 

Electromagnetic radiation interacts with matter only in integer numbers of photons, each with energy Tphoton where v is the radiation frequency. 

When electromagnetic radiation interacts with matter, the oscillating electric field causes the matter to oscillate at the same frequency as the radiation. This response is expressed in terms of the induced dipole moment, which may be written... 

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