A monochromatic light wave is incident normally on a glass slab of thickness π, as shown in the figure.The refractive index of the slab increases linearly from π1 to π2 over the height β. Which of the following statement(s) is(are) true about the light wave emerging out of the slab?
A monochromatic light wave is incident normally on a glass slab of thickness π, as shown in the figure.The refractive index of the slab increases linearly from π1 to π2 over the height β. Which of the following statement(s) is(are) true about the light wave emerging out of the slab?
It will deflect up by an angle tanβ1\([\frac {(n_2^2 - n_1^2)d}{2h}]\).
It will deflect up by an angle tanβ1\([\frac {(n_2 - n_1)d}{h}]\).
- It will not deflect.
The deflection angle depends only on (π2 β π1) and not on the individual values of π1 and π2.
The Correct Option is D
Solution and Explanation
The deflection angle indeed depends only on the difference between the refractive indices (n2 - n1) and is independent of the specific values of n1 and n2. As long as the refractive index increases linearly, the deflection angle will depend solely on the difference in refractive indices.
Therefore, option (4) is correct.
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Concepts Used:
Ray Optics and Optical Instruments
Optics, deals with the determination of behaviour and the properties of light, along with its interactions with the matter and also with the instruments that are used to detect it.
Ray optics is also known as the geometrical optics and it is a branch of science which describes light propagation.
Reflection is the change in direction of light at an interface in-between two different media so that the wave-front returns into a medium from which it was originated.
Speed of light is the rate at which the light travels in free space.
A phenomenal change in image formed when the light is passed from one medium to another which is called Refraction.
Total Internal Reflection is the reflection of light when the light ray enters into a rarer medium from a denser medium and the angle of incidence is higher than the critical angle of incidence then that light ray will be reflected back to the denser medium.
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