Introduction to Prism
We must have seen the petrol spilled on the road during rainy days.
We can see the different layers of colours in that petrol
This happens due to the phenomenon of dispersion of light.
Splitting of white light into it's constituent colors is called as a dispersion of light.
Dispersion of light can be seen by using prism.
Let's learn about Prism
There exists an optical instrument that splits the white light into its composite colors.
This triangular piece of glass is known as
P
r
i
s
m
which was discovered by Issac Newton in 1666.
Let us look at the different surfaces of the prism.
Prism is a refractive medium having five plane surfaces and a triangular cross-section along it's entire length.
Among the five planar surfaces, two of them,
A
B
C
and
D
E
F
are triangular.
While the remaining three
A
D
E
B
,
A
D
C
F
and
B
E
C
F
are rectangular surfaces.
Let us now introduce some terms related to prism.
In the figure,
A
B
C
is referred to as
The Principal Section of Prism
and
∠
A
is called as
Angle of Prism
.
A
D
E
B
and
A
D
F
C
are called
Refracting Surfaces
as light gets refracted through these surfaces .
Both these Refracting Surfaces coincide at
A
D
which is called
The refractive edge
.
B
C
E
F
is known as the
B
a
s
e
of the prism
Revision
Prism is a refractive medium which consists of five planar surfaces and has a triangular length cross-section.
Out of these
5
surfaces,
3
are rectangular and
2
are triangular.
A
B
C
→
The Principal Section of Prism
∠
A
→
Angle of Prism
A
D
E
B
and
A
D
F
C
→
Refracting Surfaces
A
D
→
Refracting Edge
B
C
E
F
→
B
a
s
e
of the prism
The End