Ans. LAWS OF REFRACTION OF LIGHT
(i) The incident ray, the refracted ray, and the normal at the-point of incidence all lie in the same plane.
Substance
Iidnof Refraction (a)
Diamond
2.42
Cubic Zirconia
2.21
Glass (flint)
1.66
Glass(crown)
1.52
Ethyl Alcohol
1.36
Ice
1.31
Water
1.33
Air
1.00
(ii) The ratio of the sine of the angle of incidence i to the sin of the angle of refraction r is always equal to a constant.
i.e.
sin i
sin r
= constant
where the ratio sin i/sin r is known as the refractive index of the second medium with respect to the first medium. So, we have
sin i sin r
it is called Sneil s law.