Refraction of Light by 2E4 Sudha

I learnt : when the light moves from air to glass,it is refracted towards the normal & when the light moves from glass to air,it is refracted away from the normal.

And also that light from an object bends as it comes out of water ; but our brain thinks the light has moved in a straight line. So, the object appears to be at a higher position than it actually is.

the key points :
Light is bent or refracted when it passes from one transparent material into another,such as from air to glass and vice versa.

Two effects of refraction are (a)an object in water appears nearer to the surface than it really is and (b)an object such as a stick placed in water appears to be bent.

Refraction is the change in direction of a wave due to a change in its speed. This is most commonly seen when a wave passes from one medium to another.
In optics, refraction occurs when light waves travel from a medium with a given refractive index to a medium with another. At the boundary between the media, the wave's phase velocity is altered, it changes direction, and its wavelength increases or decreases but its frequency remains constant.

For example, a light ray will refract as it enters and leaves glass; understanding of this concept led to the invention of lenses and the refracting telescope.