1. Wave Interactions

2. Wave Interactions…
Reflection: occurs when a wave bounces back after striking a barrier
All waves can be reflected.
Reflected sound waves are called echoes.
Sunlight is being reflected off of the moon at night.
Water waves reflect off a shoreline.

3. Reflection

4. More wave interactions…
Refraction is the bending of a wave as it passes at an angle from one medium to another. Speed of refraction depends on the medium.

5. Refraction Sound from liquid to gas Light from gas to solid
Light from gas to liquid

6. (1) Reflection or (2) refractionB E C D

7. Wave interactions…
Diffraction: the bending of waves around or through an opening; diffraction depends on wavelength and the size of barrier/opening

8. Diffraction
Can be more than one opening or can bend around a corner.

9. 1) Reflection 2) refraction 3) diffraction
Which one bends waves as it moves from one medium to another?
Which one is when waves move through the opening of a barrier?
Which one is when waves bounce off a barrier?
Which one is when waves bend around a barrier?

10. 1) Reflection 2) refraction 3) diffractionB

11. Interference Interference: the result of 2 or more waves overlapping.
a. constructive interference: increases the amplitude of a wave

12. Constructive Interference

13. Constructive interference – where the waves cross!

14. Amplitudes/height add together (build/construct)

15. Destructive Interference
b. destructive interference: decreases the amplitude of a wave

16. Destructive Interference

17. Areas between waves – destructive interference

18. Amplitude decreases (destructs)

19. 1) Diffraction 2) Constructive Interference 3) Destructive InterferenceB A C

20. More on interference waves
Can create standing waves
Standing wave is a wave that forms a stationary pattern in which portions of the wave are at the rest position.

21. Interference Waves can be deadly!
July 1, Tacoma Bridge Accident

22. Resonance Frequency
A natural frequency of vibration which can result in a responding vibration – a resonance.
Ex. Tuning a piano