Answer the following question:

Two students are separated by a 7 m partition wall in a room 10 m high. If both light and sound waves can bend around obstacles, how is it that the students are unable to see each other even though they can converse easily?

Bending the waves by obstacles at a large considerable angle only if the size of the obstacle is comparable to the wavelength of the waves.


If the wavelength of light waves is too small compared to the size of the obstacle, then the diffraction would not be considerable. Hence, the students are unable to see each other. On the other hand, the size of the wall is comparable to the wavelength of the sound waves. Thus, the bending of the waves takes place at a large angle. Hence, the students are able to hear each other.


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