The principle of superposition says that the resulting wave is the sum of the two individual wave functions.
Two types of wave interference:
CONSTRUCTIVE INFERENCE:
a type of interference that occurs at any location along the medium where the two interfering waves have a displacement in the same direction. In other words, both waves have an upward displacement; consequently, the medium has an upward displacement that is greater than the displacement of the beginning waves.
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For example, if the crests (or troughs) of two lwaves are in the same direction, they combine together to create an amplified wave. |
DESTRUCTIVE INFERENCE:
a type of interference that occurs at any location along the medium where the two interfering waves have a displacement in the opposite direction. In other words, when two waves with
opposite displacements (one wave displaced up and the other down) meet at a given location, the upward pull of one wave is balanced (canceled or destroyed) by the downward pull of the other wave.
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In the opposite scenario, where the crests of one wave are aligned with the troughs of another, they cancel each other out. |
