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some energy depending upon the direction along which incident photon is scattered. From these two effects, it appears as if a particle (photon of radiation) is colliding against and another particle (electron). Hence, it became necessary to assume that in photoelectric effect and Compton effect, radiation exhibits particle nature. The various phenomena concerning radiation can be divided into three parts : (1) The phenomena such as interference, diffraction, polarisation, etc.
in which interaction of radiations takes places with radiation itself. Such phenomena can be explained on the basis of electro-magnetic
(wave) nature of radiation only. (ii) The phenomena such as photoelectric effect, Compton effect, etc.
in which interaction of radiations takes place with radiation itself. Such phenomena can be explained on the basis of quantum (particle)
nature of radiation. (ii) The phenomena such as rectilinear propagation, reflection, refractin,
etc. in which the interaction of radiation takes place neither with itself, nor with matter. Such phenomena can be explained on the
basis of either of the two natures of the radiation. It may be pointed out that in a particular experiment, radiation has a particular nature i.e. either it possesses wave nature or particle nature. De-Broglie Waves Radiation behaves both as wave and particle. In 1924, Loius de-Broglie put forward a hypothesis that matter should also possess dual nature. The following observations led him to the duality hypothesis for matter: 1. The whole energy in this universe is in the form of matter and
electromagnetic radiation. 2. The nature loves symmetry. As the radiation has got dual nature,
matter should also possess dual nature. Thus, according to de-Broglie, a wave is associated with every moving particle. These waves called de-Broglie waves or matter waves. According to quantum theory of radiation, energy of a photon is given by Erhv
Therefore, the wavelength of the photon is given by THAT YFIT 3481 - 99, 2004
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