1. Wave Interactions
When two waves come together, they do not bounce back from each other – instead they pass through one another.
Ex: Sound waves are unaffected by other sound waves (can hear more than one thing at a time)
This is because mechanical waves are not matter, but are displacements of matter, and therefore they can occupy the same space at the same time.
Superposition = the combination of two overlapping waves

2. Wave Interactions
As waves pass through one another, they can form interference patterns
Interference = when two
waves superimpose to form a
resultant wave of greater or
lower amplitude
Interference can be seen
with all types of waves (light,
sound, mechanical, etc.)

3. Wave Interactions Types of interference
Constructive interference = when the crest of a wave meets a crest of another wave of the same frequency at the same point. The magnitude of the displacement is the sum of the individual magnitudes (bigger crest)
Destructive interference = when the trough of a wave meets the crest of another wave of the same frequency at the same point. The magnitude of the displacements is equal to the difference in the individual magnitudes.

4. Wave Interactions
Constructive Interference: add the amplitude of each wave to find the resultant displacement
Destructive Interference: subtract (or add the negative) of the amplitude of each wave to find the resultant displacement.

5. Wave Interactions
Superposition Principle = when two or more waves travel through a medium at the same time, the resultant wave is the sum of the displacements of the individual waves at each point.
Wave superposition - YouTube
In destructive interference, when the resultant displacement is a straight line, complete destructive interference occurs.

6. Wave Interactions
Reflection = when a wave reaches a boundary and the pulse bounces back in the opposite direction
At a fixed
boundary
(wall, person)
waves are
reflected and
inverted.

7. Wave Interactions
Standing waves = a wave pattern resulting when two waves with the same frequency, wavelength, and amplitude travel in opposite directions and interfere.
Node = a point that has zero displacement.
Antinode = point of largest displacement halfway between two nodes.

8. Wave Interactions
To determine the wavelength of the standing wave, each loop corresponds to either a crest or a trough. Therefore, the first image will have a wavelength of 2L, the middle image is showing a complete wavelength, and the bottom image is showing a wavelength of 2/3 L. L