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A fish is a little away below the surfac...

A fish is a little away below the surface of a lake. If the critical angle is `49^(@)` , then the fish could see things above the water surface with in an angular range of `theta^(@)` where

A

`theta=49^(@)`

B

`theta=90^(@)`

C

`theta = 90^(@)`

D

`theta = 24(1^(@))/(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
From figure given in question `theta=2c=98^(@)`.
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A2Z-GEOMETRICAL OPTICS-Section D - Chapter End Test
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  2. Wavelength of light used in an optical instrument are lambda(1)=400 Å ...

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  4. A light ray is incident perpendicularly to one face of a 90^circ prism...

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  5. A thin glass (refractive index 1.5) lens has optical power of -5D in a...

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  6. Which of the following graphs is the magnification of a real image aga...

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  7. A thin prism P(1) with angle 4degree and made from glass of refractive...

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  8. A converging lens is used to form an image on a screen. When the upper...

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  9. A diminished image of an object is to be obtained on a screen 1.0 m fr...

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  10. An object 15cm high is placed 10cm from the optical center of a thin l...

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  11. A lens forms a virtual, diminished image of an object placed at 2 m fr...

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  12. When the distance between the object and the screen is more than 4 f....

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  13. a convex lens of power +6 diopter is placed in contact with a concave ...

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  14. A concave lens of focal length 20 cm product an image half in size of ...

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  15. A convex lens of focal length 1.0m and a concave lens of focal length ...

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  16. If in a planoconvex lens, the radius of curvature of the convex surfac...

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  17. A convex lens A of focal length 20cm and a concave lens G of focal le...

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  18. The radii of curvature of the two surfaces of a lens are 20cm and 30 c...

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  19. A lens forms a virtual image 4 cm away from it when an object is place...

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  20. A concave lens of focal length (1)/(3)m forms a real, inverted image t...

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  21. An object is placed at a distance of f//2 from a convex lens. The imag...

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