. State the law of refraction of light that defines the refractive index of a medium with respect to the other

Express it mathematically. How is refractive index of any medium 'A'  with  respect  to a medium 'B' related  to the  speed  of propagation of light  in  two media  A and  B? State the name of this constant when one medium is vacuum or air. The refractive   indices of glass and water with respect to vacuum   are 3f1.and 4/3 respectively. If the speed of light in glass is 2x 108 m/s, find  the  speed  of light  in (i)vacuum,  (ii) water.


Best Answer

Ans. The second law of refraction gives a relationship between the angle of incidence and  the angle of refraction. This

law is also known as Snell's Law of refraction. According to the Snell's law, "The ratio of sine of angle of incident to the sine of refraction is constant for a given pair of media.

sin i/sin r = n constant.    This constant is called refractive index.

Example: A ray of light travelling in air enters into glass and gets refracted

law of reflection of light

law of reflection of light


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