1. 1. Complete Warm-Up for April 9th. Work
with your shoulder partner first. Then
swap and compare answers with the rest
of your team.
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2. The team with the most correct answers
are “King/Queen for the day” and the
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rolling chairs.
3. Get your journal ready. Add one page of
guided notes to the next available page.
4. Time Limit: 8 minutes

2. S8P5:
Students will explore the
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wave nature of sound and
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electromagnetic radiation.

3. a. Identify the characteristics of electromagnetic and
mechanical waves.
b. Describe how the behavior of light waves is
manipulated causing reflection, refraction diffraction,
and absorption).
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c. Explain how the human eye sees objects and colors
in terms of wavelengths.
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d. Describe how the behavior of waves is affected by
medium (such as air, water, solids).
e. Relate the properties of sound to everyday
experiences.
f. Diagram the parts of the wave and explain how the
parts are affected by changes in amplitude and pitch.

4. How can light and
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sound be used as
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tools?

5. What happens when a waves
encounters a boundary (a new
medium)?
1. Absorption
2. Reflection
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3. Transmission – to pass through
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7. Energy in wave is
transformed into a
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different form of
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energy, usually
thermal energy.

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9. 1.Reflection
2.Refraction
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3.Diffraction
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4.Interference
5.Polarization

10.  occurs when a wave strikes an
object and bounces off
 occurs with all types of waves
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 obeys the Law of Reflection – the
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angle of incidence is equal to the
angle of reflection

11.  When a wave enters a new medium at an
angle, one side of the wave changes speed
before the other side, causing the wave to
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bend.
• amount of bending depends on the speed of
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light in both materials
• the greater the difference between the speeds
of light in the two media, the more the light is
bent

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13. REFRACTION IN NATURE
Wave speed depends
on the medium
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Click on picture for internet animation

14.  bending of light around a
barrier
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 occurs with all types of waves
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15. Diffraction
• A wave spreading
• A wave passes a barrier or moves through a hole in a barrier…
• it bends and spreads out
• ex: a harbor
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17. DIFFRACTION
when a wave bends around an edge or
spreads through an opening
• familiar examples: sound
waves (speakers in a room)
and water waves (breaker
opening in harbors)
• the amount of diffraction
increases with increasing λ
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18. White light can be separated into the
visible spectrum colors by bending
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the light with refraction or
diffraction
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 red light is bent the least
 violet light is bent the most

19. • caused when light waves overlap
each other
a) constructive – interact to build
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up wave
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b) destructive – interact to reduce
wave

20. INTERFERENCE
when 2 or more waves meet while traveling
in the same medium (overlapping waves)
 the NET displacement (amplitude) is the sum
of the amplitude of the waves
 Constructive or destructive interference
 Creates standing waves & beats
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21. Interference
• the result of two or more sound
• waves overlapping
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22. Interference
• Waves combining
• Constructive interference
• Waves add together to make a larger amplitude
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+
+ =
=

23. CONSTRUCTIVE INTERFERENCE
larger displacement (larger amplitude)
crest overlaps crest 
or
tough overlaps trough
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24. CONSTRUCTIVE INTERFERENCE
 Resonance
 When an object vibration at a particular frequency
 Seen in musical instruments, especially strings
 Sympathetic resonance
When one vibrating object induces a vibration in
another object
 Soldiers do not walk in
formation across bridges
 Tacoma Narrows Bridge
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25. Interference (cont.)
• Destructive interference
• Waves add together to make a smaller amplitude
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+
+ =
=

26. DESTRUCTIVE INTERFERENCE
smaller displacement (smaller amplitude)
crest overlaps trough 
displacement/
amplitude is reduced
crest cancels trough 
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27. 4/9/12
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Different sounds that you hear include
(A) noise, (B) pure tones, and (C) musical
notes.

28. BEATS: INTERFERENCE
Overlapping waves of different f (frequencies)
 In music interference creates “beats”
(changes in loudness & softness)
Wave 1 (red) and
Wave 2 (blue)
combine to form beat pattern (in green)
High amplitude = LOUD
Low amplitude = soft
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29.  A polarizing filter acts as though
it has tiny slits in one direction.
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Only some of the light (vibrating in
the same way as the slit) can pass
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through a polarized filter

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