Reflection of Light by 2E3 Ying jie

The bouncing of light off a mirror is called reflection.
Law of reflection
The ray of light approaching the mirror is known as the incident ray .The ray of light which leaves the mirror is known as the reflected ray .
At the point of incidence where the ray strikes the mirror, a line can be drawn perpendicular to the surface of the mirror, and this is called normal line.
The angle between the incident ray and the normal is known as the angle of incidence.
The angle between the reflected ray and the normal is known as the angle of reflection.
The law of reflection states that when a ray of light reflects off a surface THE ANGLE OF INCIDENCE = ANGLE OF REFLECTION .
Another law of reflection ,is Light travels in straight lines.

In a plane mirror ,
1. Image is Upright and of the same size of the object
2. Images lies as far behind the mirror as the object is in front of the mirror .
3. Image is laterally inverted .
4. image is always virtual image .
An image that cannot be formed on a screen is called VIRTUAL IMAGE.

Uses of the plane mirror,
Helps the driver to see the traffic behind , Makes room look bigger , Check their appearance .

Two types of reflection ,
Regular reflection – When a parallel beam of light hits a smooth surface , it is reflected as a parallel beam . An image is formed.

Diffuse reflection – When a beam of light hits the rough surface , individual rays are reflected in different directions. No image is formed .

Uses Of Curved mirrors ,

Convex Mirrors- Is a fish eye mirror or diverging mirror, is a curved mirror in which the reflective surface bulges toward the light source.
Upright images that are smaller than object. By the same time it allows many things to be seen.

Uses of Convex Mirrors :
1.Camera phones use convex mirrors to allow the user correctly aim the camera while taking a self-portrait.
2.The passenger-side mirror on a car is typically a convex mirror. It gives a safety warning "Objects in mirror are closer than they appear", to warn the driver of the convex mirror's distorting effects on distance perception.

Concave mirrors – Upright magnified images if the object is close to the mirror . If it is further away , the image is inverted .

Uses of Concave Mirrors :
Dentist mirror magnifies the image of our teeth .
Used to reflect light into microscope.