DIFFRACTION   Sound waves propagate spherically. For smaller wavelengths and greater distance from the source, we can perceive them as waves with a relatively flat front and a direction perpendicular to it. The ability of sound waves in meeting obstacles to go around them, penetrating into the area behind them, is called diffraction. Without a diffraction the sound would be audible only in a situation of direct sight to the sound source.By the diffraction we can hear sound … Read entire article »