Change in the path of light ray when it passes from one medium to another medium is called refraction of
light.
Speed of light is different in different media. The speed of light changes when it passes from one medium to another is the main causes of refraction.
Examples of refraction of light:
A pencil partially immersed in water appears to be bent because of the refraction of light coming from the part of pencil that is under water.
A lemon kept in water in a glass tumbler appears to be ** than its actual size, when viewed from the sides.
