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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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