1. Wave Interactions

2. 6 Wave Interactions
When a wave encounters a surface, 6 interactions can occur
Reflection
Absorption
Refraction
Polarization
Interference
Diffraction

3. Reflection
Reflection – when a wave bounces off a material and goes in a new direction

4. Refraction
Refraction – when a wave passes through a different material and bends

5. Refraction

6. Absorption
Absorption – when a wave is absorbed by the material and may disappear

7. Polarization
Polarization – when EM waves move through a filter that blocks one direction of the wave.
VIDEO

8. Diffraction
Diffraction – when a wave bends around corners

9. Interference
When 2 or more waves overlap, they interfere with each other to either add or subtract in amplitude.

10. Interference
Interference – when two or more waves meet in the same medium
Constructive Interference – when two waves add up to make a larger amplitude wave
Destructive Interference – when waves add up to make a smaller or zero amplitude wave (cancel each other out)

11. Constructive Interference

12. Constructive Interference
Crest to Crest Trough to Trough

13. Destructive Interference

14. Destructive Interference
Crest to Trough

16. Check for Understanding!1. 2.

17. Result of Interference
Resonance – occurs when vibrations travelling through an object match the object’s natural frequency
Also occurs when one object vibrates another object without touching it

18. Result of Resonance

19. Tacoma Narrows Bridge collapsing
Result of Resonance
Glass shattering
Tacoma Narrows Bridge collapsing
Chinook Helicopter