Question

State the laws of refraction. What is the meaning of "the refractive index of crown glass is $1.52$"?

Answer 1

Laws of refraction :

There are two statements for this law which are as follows :

(1) The incident ray, refracted ray and normal lie in the same plane.

(2) Refractive index of a material is given by the ratio of sin of angle of incident to the sine angle of refraction.

ie $\mu =\frac{\sin \left(i\right)}{\sin \left(r\right)}$

the refractive index of crown glass is $1.52$ means: refractive index of crown glass is $1.52$ with respect to air. And the speed of light in crown glass will be 1.52 times slower in crown glass than in a vacuum.