Refraction of Light by 2E1 Emily

REFRACTION.
If you have ever half submerged a straight stick into water, you have probably noticed that the stick appears bent at the point it enters the water.This optical effect is due to refraction.

Refraction is the change in direction of a wave due to a change in its speed.

Refraction happens when light passes from one medium to another.
When light passes from one medium to another, light from less dense media to a denser media will slow down and it is refracted towards the normal. But when light passes from denser media to less dense media, it will speeds up and it is refracted from the normal.

REFRACTIVE INDEX
The refractive index of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium.

EFFECTS OF REFRACTION
refraction has some unusual effects in everyday life. some examples are :
- when you place a glass block on top of your textbook, and observe. The words will appear to be nearer to the surface of the glass than they actually are.
- the object appears to be at a higher position than it actually is. for this reason, a swimming pool appears shallower than it really is.
- a pencil inside a beaker filled with water will appear to be bent.

From all the information i have gained, i have learnt that refraction occurs in everyday life. It is very interesting to know how it happens and what are the unusual effects caused by refraction.

The Key point of this topic is : Refraction happens when light changes direction when it passes from one transparent material into another. Refraction will cause an object appears to be at higher position than it actually is.

Science Textbook Chapter 8, Refraction. http://www.ps.missouri.edu/rickspage/refract/refraction.html http://en.wikipedia.org/wiki/Refraction