Important terms related with refraction of light

Angle of Incidence

To get the angle of incidence, first draw a normal NON’ perpendicular at the point O. Now, the angle of incidence may be defined as the angle between the incident ray and normal at the point of incidence. It is represented by letter ‘i’.

Angle of Refraction

The angle of refraction is the angle between the refracted ray and normal at the point of incidence. It is represented by letter ‘r’.

Medium

A medium is any transparent substance through which light can pass. It is of two types

1. Optically Rarer Medium

An optically rarer medium is that medium in which the speed of light is more. For example, water is an optically rarer medium than glass and air is an optically rarer medium as compared to both water and glass.

2. Optically Denser Medium

 An optically denser medium is that medium in which the speed of light is less. For example, water is an optically denser medium than air, and glass is an optically denser medium than both water and air.

Test Your Understanding and Answer These Questions:

1. Define medium.
2. What are types of a medium?
3. Define optically denser medium.
4. Define optically rarer medium.
5. Give an example of an optically denser medium.
6. Give an example of an optically rarer medium.
7. Define angle of incidence for refraction of light.
8. Define angle of refraction for refraction of light.