Wave interference is the phenomenon that occurs when two waves meet while traveling along the same medium. Interference may be constructive or destructive.
Standing Waves
Standing waves are produced whenever two waves of identical frequency interfere with one another while traveling in opposite directions along the same medium. This is very popular with many musical instruments.
- Sound waves can interfere constructively or destructively with each other to dramatically change what you hear.
- Destructive interference can make sounds quieter or even cancel out; constructive interference can make sounds much louder.
When waves reflect back they interfere with the next wave coming in both constructively and destructively to create a "standing wave"
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As these people create a transverse wave the waves reflect back and forth at either end. When the waves bounce back they interfere with each other to create a wave that appears to be "standing." This kind of interference can create louder sounds in musical instruments.
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Nodes vs. Antinodes
- All standing waves have places, called nodes, where there is no wave motion, and antinodes, where the wave is largest. It is the placement of the nodes that determines which wavelengths "fit" into a musical instrument.
- Sound waves reflect in tubes or some musical instruments to produce standing waves which reinforce sound through constructive interference to make the sound louder.
Experiment With Standing Waves
Interactive Guide:
- Select preset waves on the right side. Select two fixed ends then select next harmonic +. Then play around with any of the settings you like.
- Play with the show as rope and show as sound setting on the right side. How are they similar? How are they different?
- Select custom waves on the right side and see what kind of standing waves you can create.
Video Guide:
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Video Guide:
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Topic Tips
- Standing waves are produced whenever two waves of identical frequency interfere with one another while traveling opposite directions along the same medium. This can produce a louder sound.