The document discusses two types of waves - transverse waves where the oscillations are perpendicular to the direction of motion and longitudinal waves where the oscillations are parallel. It covers wave characteristics like frequency, amplitude and wavelength and how waves interact with objects through reflection, refraction, diffraction and absorption as well as interference when two waves meet. Key concepts are explained and examples are provided to illustrate wave behavior and 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
4

5. Transverse Waves
The difference between the two types:
5

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.
21

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
26

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