Reflection of Light
The phenomenon of bouncing back of light into the same medium by the smooth surface is called reflection.
Incident light
Light which falls on the surface is called incident light.
Reflected light
Light which goes back after reflection is called reflected light
Angle of incidence
The angle between the incident ray and the normal.
Angle of reflection
The angle between the reflected ray and the normal.
Mirror
The surface which can reflect the light is a mirror.
Plane Mirror
If the reflecting surface is a plane then the mirror is plane.
Spherical Mirror
If the reflecting surface is part of the hollow sphere then the mirror is a spherical mirror. The spherical mirror is of two types:
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Convex mirror: In this mirror reflecting surface is convex. It diverges the light so it is also called a diverging mirror.
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Concave mirror: In this mirror reflecting surface is concave. It converges the light so it is also called converging mirror.
Refraction of Light
The bending of light at the interface of two different mediums is called Refraction of light.
Refractive Index
It represents the amount or extent of bending of light when it passes from one medium to another. There are two types of refractive index
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Relative refractive index and
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Absolute refractive index.
Incident ray
It is incoming ray on the refracting surface.
Refracted ray
It is an outgoing ray from the refracting surface.
Angle of incidence (i)
It is the angle between incident rays and perpendicular line (normal) at the point of incidence.
Angle of refraction (r)
It is the angle between refracted rays and perpendicular line (normal) at the point of incidence.
The topics discussed in this chapter are as follows:
- Nature of Light
- Laws of Reflection
- Characteristics of Light
- Propagation of Light
- Plane mirror
- Principle of Reversibility of Light
- Spherical mirrors
- Mirror formula and magnification
- Refraction through a glass slab and refractive index
- Spherical lens
- Lens formula, Magnification and Power of lens