RAY OPTICS AND OPTICAL INSTRUMENT - Refraction of Light
The binding of the X-ray of light passing from one medium to the other medium is called Refraction.
AO – Incident ray
OB – refracted ray
Angle i – Incident angle
Angle r – Refracted angle
Laws of Refraction: The ratio of the sign i of the angle of the incidence to the angle of refraction ( r) is a constant called refractive index.
1n2 is the refractive index of second medium.
If first medium is air, then velocity of light (v = c) and velocity of light is second medium (v2 = v)
1n2 = c / v (absolute refractive index)
Absolute refractive index 1st medium
an2 = c / v2
Refractive index of 2nd medium with respect to 1st medium
Second Law: The incident ray, refracted ray and the normal to the interface at the point of interface, all lie in same plane.