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A pole of length 1.00 m stands half dipp...

A pole of length 1.00 m stands half dipped in a swimming pool with water level 50.0 cm higher than the bed. The refractive index of water is 1.33 and sunlight is coming at an angle of 45° with the vertical. Find the length of the shadow of the pole on the bed.

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The correct Answer is:
A, C
Shadow length `=BA=BD+DA`
`=0.5+0.5 tan r `
Now `1.33=(sin 45^@)/(sinr)`
`rarr sinr=1/(1.33sqrt2)=0.53`
`rarr cosr=sqrt(1-sin^2r)`
`=sqrt(1-(0.53)^2)=0.85`
So, `tanr=0.6235`
`So shadow length `=(0.5)(1+0.6235)`
`=81.2 cm`
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HC VERMA-GEOMETRICAL OPTICS-Exercises
  1. A converging mirror M1 a point source S and a diverging mirror M2 are ...

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  2. A light ray falling at an angle of 45^@ with the surface of a clean sl...

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  3. A pole of length 1.00 m stands half dipped in a swimming pool with wat...

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  4. A small piece of wood is floating on the surface of a 2.5 m deep lake....

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  5. An object P is focussed by a microscope M. A glass slab of thickness 2...

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

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  7. Locate the image of the point P as seen by the eye in the figure

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

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

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

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

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

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

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  14. An optical fibre (mu = 1.72) is surrounded by a glass coating (mu= 1.5...

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

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

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

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

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

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

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