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In a 10 m high room a partition of heigh...

In a 10 m high room a partition of height 7m separates two students on either side. Both light and sound waves can deviate from their path if they experience any obstruction. Then why is it that the two students can converse with each other even if one cannot see the other?

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For diffraction to occur, the size of the obstacle should be comparable to the wavelength. The wavelength of sound waves `(approx 0.33 m)` being much larger than wavelength of light waves`(approx 10^(-7)m)` sound wave can be diffracted through the edges of much larger obstacles like walls or partitions.On the other hand, wavelength of light is much smaller than the height of the partition making diffraction impossible. So the two boys can hear but cannot see each other.
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