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An optical fibre (RI = 1.72) is surround...

An optical fibre (RI = 1.72) is surrounded by a glass coating (RI= 1.50). Find the critical angle for total internal reflection at the fibre-glass interface.

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The correct Answer is:
A
`mu_1sintheta_c=m_2sin90^@`
`sintheta_c=1.50/1.72`
`rarr theta_c=sin^-1[75/88]`
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HC VERMA ENGLISH-GEOMETRICAL OPTICS-Exercises
  1. A cylindrical vessel, whose diameter and height both are equal to 30 c...

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  2. A light ray is incident at an angle of 45^@ with the normal to a sqr...

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  3. An optical fibre (RI = 1.72) is surrounded by a glass coating (RI= 1.5...

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  4. A light ray is incident normally on the face AB of a right-angled pris...

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  5. Find the maximum angle of refraction when a light ray is refracted fro...

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  6. Light is incident from glass (mu=1.5) to air. Sketch thevariation of t...

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  7. Light is incident from glass (mu = 1.50) to water (mu = 1.33) find th...

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  8. Light falls from glass (mu=1.5) to air. Find the angle of incidence fo...

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  9. A point source is placed at a depth h below the surface of water (refr...

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  10. A container contains water up to a height of 20 cm and there is a poin...

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  11. Find the angle of minimum deviation for an equilateral prism made of a...

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  12. Find the angle of deviation suffered by the light ray shown in figure....

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  13. A light ray, going through a prism with the angle of prism 60^@, is fo...

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  14. Locate the image formed by refraction in the situation shown in figure

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  15. A spherical surface of radius 30 cm separates two transparent media A ...

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  16. Figure shows a transparent hemisphere of radius 3.0 cm made of a mate...

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  17. A small object is embedded in a glass sphere (mu =1.5) of radius 5.0 c...

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  18. A biconvex thick lens is constructed with glass (mu = 1.50). Each of t...

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  19. A narrow pencil of parallel light is incident normally on a solid tran...

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  20. One end of a cylindrical glass rod (mu = 1.5) of radius 1.0 cm is roun...

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