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Answer the following questions: (d) Tw...

Answer the following questions:
(d) Two students are separated by a 7 m partition wall in a room 10 m high. If both light and sound waves can bend aroundobstacles, how is it that the students are unable to see each other even though they can converse easily.

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For diffraction or bending of waves by obstacles/apertures by a large angle, the size of the latter should be comparable to wavelength. If the size of the obstacle/aperture is much too large compared to wavelength, diffraction is by a small angle. Here the size is of the order of a few metres. The wavelength of light is about `5xx 10^(-7m)`, while sound waves of, say, 1 kHz frequency have wavelength of about 0.3 m. Thus, sound waves can bend around the partition while light waves cannot.
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NCERT GUJARATI-WAVE OPTICS-EXERCISES
  1. In a double-slit experiment the angular width of a fringe is found to ...

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  2. What is the Brewster angle for air to glass transition? (Refractive in...

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  3. Light of wavelength 5000 Å falls on a plane reflecting surface. What a...

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  4. Estimate the distance for which ray optics is good approximation for a...

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  5. The 6563Å Halpha line emitted by hydrogen in a star is found to be red...

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  6. Explain how Corpuscular theory predicts the speed of light in a medium...

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  7. You have learnt in the text how Huygens’ principle leads to the laws o...

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  8. Let us list some of the factors, which could possibly influence the sp...

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  9. For sound waves, the Doppler formula for frequency shift differs sligh...

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  10. In double-slit experiment using light of wavelength 600 nm, the angula...

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  11. Answer the following questions: (a) In a single slit diffraction exp...

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  12. Answer the following questions: (b) In what way is diffraction from ...

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  13. Answer the following questions: (c) When a tiny circular obstacle is...

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  14. Answer the following questions: (d) Two students are separated by a ...

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  15. Answer the following questions: (e) Ray optics is based on the assum...

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  16. Two towers on top of two hills are 40 km apart. The line joining them ...

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  17. A parallel beam of light of wavelength 500 nm falls on a narrow slit a...

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  18. Answer the following questions: (a) When a low flying aircraft passe...

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  19. Answer the following questions: (b) As you have learnt in the text, ...

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  20. In deriving the single slit diffraction pattern, it was stated that th...

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