A light ray falls on one of the faces of a priem at an ange war so that it sutters ange of minimum deviation of 30°. Find the ange of priem and ange vetration at the given surface, (Ans 50', 25")
Answers
Explanation:
Given: A light ray falls on one of the faces of a prism at an angle 40
o
so that it suffers angle of minimum deviation of 30
o
.
To find the angle of prism and angle of refraction at the given surface
Solution:
According to the given criteria,
Angle of incidene, i=40
∘
Angle of minimum deviation, δ
m
=30
∘
We know
δ
m
=2i−A, where A is refracting angle of theprism
⟹A=2i−δ
m
⟹A=2(40)−30
⟹A=50
∘
is the required angleof the prism.
And we also know in case of minimum deviation
A=2r, where r is refraction angle
So, r=
2
A
=
2
50
⟹r=25
∘
is the required angle of refraction.
Explanation:
We know
δ
m
=2i−A, where A is refracting angle of theprism
⟹A=2i−δ
m
⟹A=2(40)−30
⟹A=50
∘
is the required angleof the prism.
And we also know in case of minimum deviation
A=2r, where r is refraction angle
So, r=
2
A
=
2
50
⟹r=25
∘
is the required angle of refraction.