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A small piece of wood is floating on the surface of a 2.5 m deep lake. Where does the shadow form on the bottom when the sun is just setting? Refractive index of water = 4/3

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The correct Answer is:
B, C, D
Height of the lake =2.5 m
When the sun is just setting q is approximately =900
`:. (sini)/(sinr)=mu_2/mu_1`
`rarr 1/(sinr)=(4/3)/1`
`rarr sinr=3/4 rarr r=49^@`
Thus (x/2.5)=tanr=1.15`
`rarr x=2.5xx1.15=2.8m`
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HC VERMA-GEOMETRICAL OPTICS-Exercises
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  3. A small piece of wood is floating on the surface of a 2.5 m deep lake....

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  5. A vessel contains water up to a height of 20 cm and above it an oil up...

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  6. Locate the image of the point P as seen hy the eye in the figure

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  7. k transparent slabs are arranged one over another. The refractive indi...

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  8. A cylindrical vessel of diameter 12 cm contains 800n cm 3 of water. A ...

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  9. Consider the situation in figure. The bottom of the pot is a reflectin...

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  10. A small object is placed at the centre of the bottom of a cylindrical ...

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  11. A cylindrical vessel, whose diameter and height both are equal to 30 c...

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

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

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

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

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

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

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

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

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

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