CONTRIBUTION OF THE SCIENTISTS #4 C. V. Raman

C. V. Raman


On 28th February 1928, Raman leads an experiment at the IACS (Indian Association for the Cultivation of Science) in Kolkata with collaborates including K.S Krishnan, on the scattering of light. When he discovered what now is called Raman Effect. It was initially clear that this discovery was of huge value. It gains further proof of the quantum nature of light. Raman Spectroscopy came to base on this phenomenon and Ernest Rutherford referred to it in his presidential address to the Royal Society in London 1929.
Raman also worked in the acoustics of musical instruments. He worked out the theory of transverse vibration of the bowed strings, based on the superposition of velocities. He was also the first to investigate the harmonic nature of the sound of Indian drums such as table
He is also interested in the properties of other musical instruments based on forced vibration such as the violin. He also investigated the propagation of sound in whispering galleries, Raman work on acoustic was an important prelude both experimentally as well as conceptually to his later work on optics and quantum mechanics
Raman and his student Nagendra Nath provided the correct theoretical explanation for the acousto-optic effect ( Light Scattering by sound waves) in a series of articles resulting in the celebrated Raman-Nath Theory. Modulators and Switching systems based on this effect have enabled optical communication components based on the laser system.

. In 1948, Raman through studying the Spectroscopic behaviour of crystals, approached in a new manner the fundamental problem of crystal dynamics. He dealt with the structure and properties of diamond, the structure and optical behaviour of numerous iridescent substances including labradorite, pearly field spar, agate, opal and pearls.
Among these other interests were the optics of colloids, electrical and magnetical anisotropy and physiology of human vision.
Raman and his student Suri Bhagavantamdiscovered that the photons of light carry angular momentum in quantum terms, photons possess a property called spin. Light and other forms of electromagnetic radiation pass their angular momentum onto atoms that absorb them.


He did a lot of experiments and also published a note on “The colour of Sea” before Raman introduce his theory, it was believed that the sea gets its blue colour from the sky or due to suspended matter in the water but Raman denied this theory and figure out the blue colour of the sea was obtained from molecular diffraction.

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