"Hai , this is nothing but , Refractive index, also called index of refraction,measure of the bending of a ray of light when passing from one medium into another. If i is the angle of incidence of a ray in vacuum (angle between the incoming ray and the perpendicular to the surface of a medium, called the normal) and r is the angle of refraction (angle between the ray in the medium and the normal), the refractive index n is defined as the ratio of the sine of the angle of incidence to the sine of the angle of refraction; i.e., n = sin i / sin r. Refractive index is also equal to the velocity of light c of a given wavelength in empty space divided by its velocity v in a substance, or n = c/v."
"Hai Friend, In optics, the refractive index or index of refraction n of a material is a dimensionless number that describes how light propagates through that medium. It is defined as, n = \frac{c}{v}, where c is the speed of light in vacuum and v is the phase velocity of light in the medium."
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"The refractive index of the rays of sunlight allows us to see the different colors in a rainbow after the rain. "
11 Jun 2016
"Hai , this is nothing but , Refractive index, also called index of refraction,measure of the bending of a ray of light when passing from one medium into another. If i is the angle of incidence of a ray in vacuum (angle between the incoming ray and the perpendicular to the surface of a medium, called the normal) and r is the angle of refraction (angle between the ray in the medium and the normal), the refractive index n is defined as the ratio of the sine of the angle of incidence to the sine of the angle of refraction; i.e., n = sin i / sin r. Refractive index is also equal to the velocity of light c of a given wavelength in empty space divided by its velocity v in a substance, or n = c/v."
11 Jun 2016
"Hai Friend, In optics, the refractive index or index of refraction n of a material is a dimensionless number that describes how light propagates through that medium. It is defined as, n = \frac{c}{v}, where c is the speed of light in vacuum and v is the phase velocity of light in the medium."
11 Jun 2016