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प्रश्न
Can the absolute refractive index of a medium be less than one?
Can the value of the absolute refractive index be lesser than 1?
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उत्तर
No, the absolute refractive index of a medium cannot be less than one because the speed of light in any medium is always less than that in a vacuum.
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संबंधित प्रश्न
After tracing the path of a ray of light passing through a rectangular glass slab for four different values of the angle of incidence, a student reported his observations in tabular form as given below:
| S.No | ∠ i | ∠ r | ∠ e |
| I | 30° | 19° | 29° |
| II | 40° | 28° | 40° |
| III | 50° | 36° | 50° |
| IV | 60° | 40° | 59° |
The best observation is
(A) I
(B) II
(C) III
(D) IV
In your laboratory you trace the path of light rays through a glass slab for different values of angle of incidence (∠i) and in each case measure the values of the corresponding angle of refraction (∠r) and angle of emergence (∠e). On the basis of your observations your correct conclusion is:
(a) ∠i is more than ∠r, but nearly equal to ∠e
(b) ∠i is less then ∠r, but nearly equal to ∠e
(c) ∠i is more than ∠e, but nearly equal to ∠r
(d) ∠i is less than ∠e, but nearly equal to ∠r
Why do we get a spectrum of seven colors when white light is dispersed by a prism?
Name a prism required for obtaining a spectrum of Ultraviolet light.
Why is the ratio of the velocities of light of wavelengths 4000Å and 8000Å in vacuum 1: 1?
How must light travel out of a substance if it is not going to be refracted?
A light ray in passing from water to a medium
(a) speeds up
(b) slows down. In each case, give one example of the medium.
How does the speed of light change when it passes from glass to water?
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In the fig. name the ray which represents the correct path of light while passing through a glass block.
Why does a fisherman aim at the tail of fish during spearfishing?
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- Will the image of all the letters be in the same place?
- If not, the state which letter will be raised to the maximum. Give a reason for your answer.
State the factors on which the angle of deviation depends.
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What do you understand by the deviation produced by a prism?
Draw ray of light bending towards the normal while passing from glass to water. Label your diagrams.
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Draw the ray diagram of a glass slab having medium A and B for the velocity of light ray VA and VB respectively and define Snell's law.
- If VB = 1.5 VA, then which medium is denser?
- What is the refractive index of A with respect to B?
- What is the refractive index of B with respect to A?
