Answer: When two longitudinal (sound) waves meet at a point where the compression of one wave coincides with the compression of the other wave and the rarefaction of one wave coincides with the rarefaction of the other wave. Then the resultant amplitude of a wave is maximum, or when compression of one wave falls on the rarefaction of the other lock and vice versa. Then the amplitude of the resultant wave is minimum. Then these effects are interference of longitudinal (sound) waves. Interference of longitudinal
A new sound wave is produced whenever two or more sound waves from different origins interact with one other at the same instant in time to create a new resultant wave. This phenomenon, known as sound interference, causes the final wave to total all previously existing waves.