Types of waves Types of wave interactions

1. Integrated Science
Unit 4, Chapter 12

2. 12.1 Two Types of Waves:
A transverse wave has its oscillations
perpendicular to the direction the wave moves.
A longitudinal wave has its oscillations in the
same direction as the wave moves.

4. Longitudinal Wave
The wave we see here is a longitudinal wave.
The medium particles vibrate parallel to the
motion of the pulse.
This is the same type of wave that we use to
transfer sound.
 show tuning fork demo
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5. Transverse Waves
The difference between the two types:
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6. 12.1 Frequency, Amplitude and
Wavelength

7. 12.2 Graphs of Harmonic Motion
Key Question:
How do waves move and interact with things?

8. *Wave Shapes
 *PlaneWaves- a wave that has crests all in a
straight line.

9. *Wave Shapes
 *CircularWaves- a wave that has circular wave
fronts that move outward from the center.

10. Plane Waves

11. Circular Waves

12. *What happens when a wave hits an
obstacle?
 *Reflection
 *Refraction
 *Diffraction
 *Absorption

14. REFLECTION

16. REFRACTION

18. DIFFRACTION

20. ABSORPTION

21. Wave Interaction
All we have left to discover is how waves
interact with each other.
*When two waves meet while
traveling along the same medium
it is called INTERFERENCE.
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22. Constructive Interference
Let’s consider two waves moving towards
each other, both having a positive
upward amplitude.
What will happen when they meet?
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23. *Constructive Interference
*They will ADD together to produce a
greater amplitude.
This is known as CONSTRUCTIVE
INTERFERENCE.
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24. Destructive Interference
Now let’s consider the opposite, two
waves moving towards each other, one
having a positive (upward) and one a
negative (downward) amplitude.
What will happen when they meet?
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25. *Destructive Interference
*This time when they add together they
will produce a smaller amplitude.
This is know as DESTRUCTIVE
INTERFERENCE.
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26. Wave Interference
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27. Check Your Understanding
 Which points will produce constructive interference and
which will produce destructive interference?
 Constructive
G, J, M, N
 Destructive
H, I, K, L, O
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28. Your Turn:
 Create a graphic organizer using the following terms:
1. Reflection
2. Refraction
3. Diffraction
4. Absorption
 Explain what the term means. (use your own words)
 Draw a picture to represent what happens.
 List Examples