Unknown facts of Optics.

 

Unknown facts of Optics.

Today in this article I will discuss on some important points of optics which are for school going students.

What is light?

Answer:-

Light is a form of energy which give us sensation  to look at.

What are photons?

Answer:-

The particles of light are known as photons.

what is medium?

Answer:-

Medium is a substance or a path through which any energy like light or sound or heat can pass easily without any obstacle.

What are the different types of medium through which light can pass?

Answer:-

Generally light can pass in two different mediums and they are:-

(1) Rarer medium

(2) Denser medium.

What are rarer and denser medium?

Answer:-

The medium through which light rays pass more faster is known as rarer medium. e.g; Air.

The mediums which are heavy and light rays pass a little slower than rarer medium

are known as denser medium.e.g; Water, Glass.

What is reflection of light?

Answer:-

Light ray which is travelling from a source through a medium (say air) in a straight line if it is obstructed by another medium or a surface then it bounce back from that medium or surface to the its 1st medium, this property of light is called reflection of light.

What are the laws of reflection?

Answer:-

There are two laws of reflections:-

(1) Incident ray,reflected ray, normal,and point of incidence all lie in same plain.

(2) The angle of incidence and angle of reflection are always equal.i.e; <i = <r

What is irregular reflection?

Answer:-

When light rays falls on a rough surface it scattered and bounce back from several points not a single point, this type of reflection is called irregular reflection.

What is refraction of light?

Answer:-

Light ray which is coming from a source through a medium in a straight line  when it enters in another medium,then it slightly change the direction of its path on the contact point of two medium, this property of light is called refraction of light.

What are the laws of refraction?

Answer:- 

               There are two laws of refraction:-

(1) Incident ray, refracted ray, normal and point of incidence all lie in same plain.

(2) The ratio of the sin of incidence angle to the sin of refraction angle is always a constant, and this constant is called refractive index of 2nd medium with respect to the 1st medium, and is denoted by ¹μ₂ . This law is also known as Snell's law.

Describe reflection of light with ray diagram .

Answer:-

In the picture,

  MN = Plain mirror.

  AO = Incident ray.

 OB = Reflected ray.

 OC = Normal.

O = Point of incidence.

<AOC = <i = Angle of incidence.

< BOC = <r = Angle of reflection.

According to the laws of reflection,

   <i = <r

and  AO, OB, OC and O all lie in same plain.

Describe refraction of light with ray diagram.

Answer:-

In the picture,

   AO = Incident ray.

   OB = Refracted ray.

   <AOC = Angle of incidence.

  

   <BOD = Angle of refraction.

    CD = Normal.

    O = Point of incidence.

According to the law of refraction,

  AO,OB, CD and O all lie in same plain.

also 

Sini /Sinr = ¹μ₂,  where ¹μ₂ is a constant, known as refractive index of second medium with respect to first medium. This is also called Snell's Law.

What is real image?

Answer:-

Light rays coming from a point source after reflection or refraction if they actually meet a fixed point then that point is called the real image of the first point. Real image has existence and can be catch in a screen.

What is virtual image?

Answer:-

Light rays coming from a source after reflection or refraction if they appear to meet from a fixed point, then that point is called the virtual image of the first point.

Virtual image has no existence and can not be catch in a screen.

What is spherical mirror?

Answer:-

Spherical mirror is a part of globe which is made of glass if we imagine.

How spherical mirror is classified?

####

Answer:-

Spherical mirror is classified in two different catagories:-

(1) Concave mirror.

(2) Convex mirror.

Define Concave mirror.

Answer:-

A spherical mirror whose lower plain surface acts as a reflecting surface is known as Concave mirror.

In the picture, MN is a concave mirror.

Define Convex mirror.

Answer:-

A spherical mirror whose upperA spherical mirror whose upper plain surface acts as a reflecting surface is known as Convex mirror.

Click Now

Note:- If you love my article and my blog then please share it and support me.

FREQUENTLY ASKED QUESTIONS:-

How many laws of reflection have ?

Answer :- There are two laws of reflection.

How many laws of refraction have?

Answer:- There are two laws of refraction.

For which phenomenon of light mirage takes place in desert ?

Answer:- Due to total internal reflection of light.

Why stars twinkle at night ?

Answer :-Due to total internal reflection of light.

What is Snell's law of refraction?

Answer :- Second law of refraction tells us that the ratio of the sin of incident angle to the angle of refraction is always a constant and this constant is also called the refractive index of 2nd medium with respect to the 1st medium . This law is also known as Snell's law of refraction.

What is refractive index of light ?

. Answer :- Second law of refraction tells us that the ratio of the sin of incident angle to the angle of refraction is always a constant and this constant is also called the refractive index of 2nd medium with respect to the 1st medium . Mathematically, it can be expressed as Sini/Sinr = ¹μ₂ Here, ¹μ₂ is the refractive index of 2nd medium with respect to 1st medium.

What is the refractive index of glass?

Answer :- Refractive index of glass = 1.5

What is the refractive index of water ?

Answer :- R.I of water = 1.33

Share this post:-

Please give your valueable feedback:-

Previous

Next