What is reflection of light?
When you look into a mirror, you see a picture of yourself. What you see is called an image. The image in a mirror is formed when light rays bounce off the mirror and travel to your eyes. This bouncing of light off a mirror is called reflection.
A flat mirror, called a plane mirror, is a good reflector of light. When a ray of light strikes the mirror at a right angle, it is reflected along the same path.
Scientists call this line the normal. When a ray of light hits a plane mirror at an angel to the normal, called the angel of incidence, it is reflected at an equal angle but on the opposite side of the normal, the angel of reflection. These two opposite side of the normal, the angle of reflection. The two angels are always equal no matter how light rays strike the mirror.
This generalization is called the law of reflection.
When does it happen?
When a ray of light hits a surface, it bounces off or reflects and then reaches our eyes. This phenomenon by which a ray of light changes the direction of propagation when it strikes a boundary between different media through which it cannot pass is described as the reflection of light
Types of reflection
There are two types of reflection – regular reflection and diffuse reflection.
When a parallel beam of light hits a smooth surface such as a plane mirror, it is reflected as a parallel beam. This is called regular reflection. An image is formed with regular reflection. That is, when we look at a smooth surface, we can see an image.
Most surfaces are actually quite rough. When a beam of light hits a rough surface, the individual rays are reflected in different directions. So no image is formed. This type of reflection is called diffuse reflection.
Uses of reflection of light and examples?
Convex mirrors are often used in shops as security mirrors because of the type of image produced by that mirror. The image is smaller but shows a wide angle view of the shop.
Concave mirrors are often used in torch lights or in the headlights of cars. The light travels in all directions from the light globe towards the mirror behind it. The rays are then reflected by the mirror and they form a beam of light (a bundle of parallel rays).
http://www.tutorvista.com/content/science/science-ii/reflection-light/reflection-light.php
http://www1.curriculum.edu.au/sciencepd/readings/ligh_reflection.htm
Textbook Page 119 , 121 & 122
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