Page 31 - WAVES

Diffraction of Sound

Radio

Radio
Cleaner

Cleaner

A cleaner can hear the sound of a radio placed nearby a corner of a wall but he cannot see

the radio. Why?

1. The cleaner can hear the radio even behind obstacles.

2. Sounds from radio to spread around the corner of the wall because of the diffraction of sound
waves.
3. The waves will experience a diffraction when pass through a single aperture or round an

obstacle.
4. Sound waves are more easily diffracted compared to light waves.

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5. This is because the wavelength of sound is much larger than the wavelength of light (~ 10 m).

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