1. Physical Science: Chapter 15: Section 3
Wave Interactions

2. Physical Science: Chapter 15 Wave Interactions
Reflection
Bouncing back of a wave as it meets a surface or boundary.

3. Physical Science: Chapter 15 Wave Interactions
Reflection: Law of Reflection
The angle of incidence is equal to the angle of
reflection
Works for
light, sound,
water waves

4. Physical Science: Chapter 15 Wave Interactions
Reflection

5. Physical Science: Chapter 15 Wave Interactions
Reflection

6. Physical Science: Chapter 15 Wave Interactions
Diffraction:
The bending of a wave as it
passes through an
opening.

7. Physical Science: Chapter 15 Wave Interactions
Diffraction:
It can also happen with light.

8. Physical Science: Chapter 15 Wave Interactions
Refraction:
The bending of waves as they pass from one
medium
into another.

9. Physical Science: Chapter 15 Wave Interactions
Refraction:

10. 1). What does the Law of Reflection state?
Mini-Quiz # 5
1). What does the Law of Reflection state?
2). What are the TWO kinds of
reflection?
3). What is the difference between reflection and refraction?
4). What is the difference between
refraction and diffraction?

11. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 5
1). What does the Law of Reflection state?
The angle of incidence equals
the angle of reflection.
2). What are the TWO kinds of reflection?
Specular and diffuse

12. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 5
3). What is the difference between reflection and
refraction?
Light “bounces off” a surface in reflection and bends as it goes into another medium.

13. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 5
4). What is the difference between refraction and diffraction?
In refraction the light bends because it goes into a different medium; in diffraction the light bends because it passes through an opening.

14. Physical Science: Chapter 15 Wave Interactions
Wave Interference
The combination of two or more
waves existing
at the same
time and place.

15. Physical Science: Chapter 15 Wave Interactions
Constructive interference
Two or more waves combine so that the resulting wave (crests and troughs) is bigger than the original waves.

16. Physical Science: Chapter 15 Wave Interactions
Wave Interference
Constructive interference

17. Physical Science: Chapter 15 Wave Interactions
Wave Interference
Constructive
interference

18. Physical Science: Chapter 15 Wave Interactions
Destructive interference
Two or more waves combine so that the resulting wave (crests and troughs) is smaller than the original waves.

19. Physical Science: Chapter 15 Wave Interactions
Wave Interference
Destructive interference

20. Physical Science: Chapter 15 Wave Interactions
Wave Interference:
Destructive
interference

21. Physical Science: Chapter 15 Wave Interactions
Sound Wave Interference: Beats
A pattern of louder and softer
sounds
created by
interference.

22. Physical Science: Chapter 15 Wave Interactions
Wave Interference: Standing Waves
A formed wave caused by
interference that APPEARS not to
move along
the medium.

23. Physical Science: Chapter 15 Wave Interactions
Wave Interference: Standing Waves
Nodes (destructive interference) are regions of no displacement
Anti-nodes
(constructive
interference)
show maximum
displacement.

24. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 6
1). Describe the difference
between constructive and
destructive interference.
2). What are the two parts of a
standing wave?

25. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 6
3). What causes “beats?”
4). How many nodes in this
standing wave?
5). How many
anti-nodes?

26. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 6
1). Describe the difference between
constructive and destructive interference.
In constructive interference the (crests and troughs of) waves add together, making bigger waves; in destructive interference they cancel out, making smaller waves.

27. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 6
2). What are the two parts of a standing wave?
Nodes (from destructive interference) and anti-nodes (from constructive interference)

28. Physical Science: Chapter 15 Wave Interactions
Mini-Quiz # 6
3). What causes “beats?”
A pattern of constructive and destructive interference in sound waves.
4). How many nodes in this wave? THREE
5). How many anti-nodes? FOUR