Book: HC Verma - Concepts of Physics Part 1

Chapter: 18. Geometrical Optics

Subject: Physics - Class 12th

Q. No. 30 of Exercises

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30
Light is incident from glass (μ = 1.50) to water (μ = 1.33). Find the range of the angle of deviation for which there are two angles of incidence.

Refractive index of glass is

Refractive index of water is

Critical Angle=

According to the question:

There will be two angles of incidence:

(1) When light ray passes through the normal

Angle of incidence =

Angle of refraction=

Angle of deviation =

(2) When light ray incident at critical angle

(As light ray is passing from glass to water)

Angle of deviation=

=

=

If angle of incidence increases beyond critical angle, total internal reflection will occur. So, the range of angle of deviation is

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