LIGHT : Refraction

Material :

What causes light to refract?

             Light changes speed as it enters from one medium to another and bends. The bend of light depends on the refractive index of the medium. Different mediums have different refractive index and density.

Refraction of light is incident ray tilt or light when it passes through two different media. Refraction of light occurs when light through two different medium density. As the density of water is greater than the density of air, while air has a density of more tenuous than the density of the glass. In general there are two kinds of refraction:

a.    Rays coming from the media more more tenuous to the media that tightly will be refracted near the normal line (i> r)

b.    Rays coming from the media more tightly into a more tenuous medium will be refracted away from the normal line.

These images shows the refraction of light:

 
The light bends as it passes from air to water.

A prism refracts light at different directions to form a rainbow.

In the refraction effect of refraction Snell's law, which reads as follows. 1. Rays come, the normal line, and the refraction ray is located in one plane. 2. Comparison between the projection and projection ray rays come to the field boundary refraction is a remains number called the relative refractive index.

The diagram below shows the refraction of light when it passes from one medium to another. The red line is the normal, which is perpendicular to the surface of the medium. As the light passes through the second medium, the light bends towards the normal because density of the second medium is greater than the first. The angle between the incoming ray and the normal is the angle of incidence. The angle between the refracted ray and the normal is the angle of refraction.

Mathematical formulation of Snell's law is :

or 

or

The symbol θ1, θ2 refers to the angle of incidence and refraction angles, v1 and v2 on the speed of light rays come and light refraction. The symbol refers to the refractive index n1 medium through which the rays come, while n2 is the refractive index of the medium through which light refraction.

 To better understand, try to see the video as an application of refraction