Emerald And Pearl Jewellery Collection 28

Emerald And Pearl Jewellery.
Fashion jewellery an_emerald_and_cultured_pearl_necklace_set and gold emerald and pearl jewellery by_fashion jewellery 

Aamir mannan. 

REFRACTIVE INDEX AND ITS MEASUREMENT

This deviation of rays of light on entering a new medium is called refraction. In figure 2.1 the rays of light, I.O, is refracted along OR  on entering the denser medium blow the surface PQ. The broken line show the path of  followed by the reflacted light. The 

extent of the bending of refraction of light on entering the stone depends upon its refracting power or 'refractive index', and this is inversely proportional to the velocity of light withing the substance. Put differently, the refractive index of a medium may be define as the velocity of light in air* divided by the velocity of light in the medium. The velocity of light in air approximately I86,000 miles per second, and light from the sun and stars travel to us at this immense speed. In quartz (rock, crystal, amethyst, etc) the velocity is reduced to approximately I20,000 and its diamond to only 76,860 miles per second. Thus diamond, in which light travels as mentioned above, at 76,860 miles per second in empty space, has a refractive index of I86,000\76,860=2.042; higher then the refractive index of any other gemstones used in
jewellery-accounting for the brilliant, adamantine lustre of the stone.