ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Cover sheet
ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
To be accepted for grading it must be in order and signed
Please go through the paper work with your student.
Test and packet due on 11/16 odd 11/15 even
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Assignment list
1. Cover
2. WCW
3. Standards
Make three questions with answers for each standard
4. Vocabulary
Bold, italic, underlined in standards- definition
(12)
5. Notes Electro-Magnetic Spectrum
Some items must be written on it from class only
IDRDP-Interference Diffraction Refraction Doppler effect
Polarization
6. Problems Electro-Magnetic Spectrum
7. Notes Properties of IDRDP
8. Problems Properties of IDRDP
9. Study Guide
PH 4. e. Students know radio waves, light, and X-rays are different wavelength bands in the spectrum of electromagnetic waves whose speed in a vacuum is approximately 3 × 10 8 m/s (186,000 miles/second).
PH 4. f. Students know how to identify the characteristic properties of waves: interference
(beats), diffraction, refraction, Doppler effect, and polarization.
Objective Understand the differences between wavelengths of Electro-Magnetic Spectrum.
Identify the processes of waves interacting; Such as
Interference, Polarization, Refraction, Diffraction and the Doppler Effect
10. CST prep
Language objective To use the distinct regions of the spectrum correctly, radio, microwave, infrared, visible, ultraviolet, X-ray, and gamma ray waves. Students can use the wavelength and frequency to describe a particular wave type. Understand the main difference between constructive and destructive interference. Explain how waves interact with other waves and materials using the terms, polarized, Doppler shifted, red-shift, blue-shift, normal and surface plain.
Standard Physics 4- Waves have characteristic properties that do not depend on the type of wave. As a basis for understanding this concept:
PH 4. e. Students know radio waves, light, and X-rays are different wavelength bands in the spectrum of electromagnetic waves whose speed in a vacuum is approximately 3 × 10
8 m/s (186,000 miles/second).
Electromagnetic waves consist of changing electric and magnetic fields. Because these fields are always perpendicular to the direction in which a wave moves, an electromagnetic wave is a transverse wave. The electric and magnetic fields are also always perpendicular to each other. Concepts of electric and magnetic fields are introduced in Standard Set 5, “Electric and Magnetic Phenomena,” in this section. The range of wavelengths for electromagnetic waves is very large, from less than nanometers (nm) for X-rays to more than kilometers for radio waves. The human eye senses only the narrow range of the electromagnetic spectrum from
400 nm to 700 nm. This range generates the sensation of the rainbow of colors from violet through the respective colors to red. In a vacuum all electromagnetic waves travel at the same speed of 3 × 10
8 m/s (or
186,000 miles per second). In a medium the speed of an electromagnetic wave depends on the medium’s properties and on the frequency of the wave. The ratio of the speed of a wave of a given frequency in a vacuum to its speed in a medium is called that medium’s index of refraction . For visible light in water, this number is approximately 1.33.

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
PH 4. f. Students know how to identify the characteristic properties of waves: interference (beats), diffraction, refraction, Doppler effect, and polarization.
A characteristic and unique property of waves is that two or more can occupy the same region of space at the same time. At a particular instant, the crest of one wave can overlap the crest of another, giving a larger displacement of the medium from its condition of equilibrium; constructive interference. Also the crest of one wave can overlap the trough of another, giving a smaller displacement; destructive interference.
The effect of two or more waves on a test particle is that the net force on the particle is the algebraic sum of the forces exerted by the various waves acting at that point. If two overlapping waves traveling in opposite directions have the same frequency, the result is a standing wave. There is a persistent pattern of having no displacement in some places, called nulls or nodes, and large, oscillating displacements in others, called
maxima or antinodes . If two overlapping waves have nearly the same frequency, a node will slowly change to a maximum and back to a node, and a maximum will slowly change to a node and back to a maximum. For sound waves this periodic change leads to audible, periodic changes from loud to soft, known as beats.
Diffraction describes the constructive and destructive patterns of waves created at the edges of objects.
Diffraction can cause waves to bend around an obstacle or to spread as they pass through an aperture. The nature of the diffraction patterns of a wave interacting with an object depends on the ratio of the size of the obstacle to the wavelength. If this ratio is large, the shadows are nearly sharp; if it is small, the shadows may be fuzzy or not appear at all. Therefore, a hand can block a ray of light, whose average wavelength is about 500 nm, but cannot block an audible sound, whose average wavelength is about 100 cm. The bending of water waves around a post and the diffraction of light waves when passing through a slit in a screen are examples of diffraction patterns. Refraction describes a change in the direction of a wave that occurs when the wave encounters a boundary between one medium and another provided that the media have either different wave velocities or indexes of refraction and provided that the wave arrives at some angle to the boundary other than perpendicular. At a sharp boundary, the change in direction is abrupt; however, if the transition from one medium to another is gradual, so that the velocity of the wave changes slowly, then the change in the wave’s direction is also gradual. Therefore, a ray of light that passes obliquely from air to water changes its direction at the water’s surface, but a ray that travels through air that has a temperature gradient will follow a bent path. A ray of light passing through a saturated solution of sugar (sucrose) and water, which has an index of refraction of 1.49, will not change direction appreciably on entering a colorless, transparent piece of quartz submersed in the solution because the quartz has an almost identical index of 1.51. The match in indexes makes the quartz nearly invisible in the sugar-water solution. Another interesting phenomenon, the Doppler Effect, accounts for the shift in the frequency of a wave when a wave source and an observer are in motion relative to each other compared with when they are at relative rest. This effect is most easily understood when the source is at rest in some medium and the observer is approaching the source at constant speed. The interval in time between each successive wave crest is shorter than it would be if the observer were at rest, and so the frequency observed is larger. The general rule, for observers moving at velocities much less than the velocity of the wave in its medium, is that the change in frequency depends only on the velocity of the observer relative to the source.
Therefore, the shriek of an ambulance siren has a higher pitch when the source approaches and a lower pitch when the source recedes. For an observer following the ambulance at the same speed, the siren would sound normal. Similar shifts are observed for visible light. Polarization is a property of light and of other transverse waves. Transverse waves are those in which the displacement of a test particle is always perpendicular to the direction in which the wave travels. When that displacement is always parallel to a particular direction, the wave is said to be ( linearly) polarized.
A ray of light emitted from a hot object, like a lamp filament or the sun, is un-polarized; such a ray consists of many component waves overlapped so that there is no special direction perpendicular to the ray in which a test particle is favored to move. The components of an unpolarized ray can be sorted to select such a special direction and so make one or more polarized rays. An unpolarized ray that is partly reflected and partly transmitted by an angled sheet of glass is split into rays that are polarized; an un-polarized ray can become polarized by going through a material that allows only waves corresponding to one special direction to pass through.

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.2 WCW
Topic: The characteristic properties of Electromagnetic Waves
Standard:
PH 4. e. Students know radio waves, light, and X-rays are different wavelength bands in the spectrum of electromagnetic waves whose speed in a vacuum is approximately 3 × 10
8 m/s
(186,000 miles/second)
Objective: Understand the interactions of Electromagnetic waves
With each other and matter
Warm-up
Describe the wave equation variables v = s_____ or v______ f = f______
λ = w______ wavelength, frequency, speed, velocity
Critical thinking v=(f) (λ) changed to this v = (2f) ( λ / ?)
Can you see the difference? ex. v= 20 = 2(10) v= 20 = 4(5)
If the Frequency doubles then the wavelength must be divided by ____?____ in-order for the speed of light to remain the same
When light and a material are involved, such as Light through air then water, the speed of light and the direction of light changes
Give the ratio for the Index of Refraction, see standard #4.E
Speed of a wave of a given frequency in a vacuum = Index of n
Speed in a medium is called that medium’s Refraction
Wrap-up
Sketch and describe- What type of EM wave? What Wavelength? Use item #5
A.
B.
D.
C.

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.2 WCW
Topic: Electromagnetic Wave: Uses, Hazards, Interactions
Standard:
PH 4. e. Radio waves, light, and X-rays are
Different wavelength bands in the spectrum of electromagnetic
Waves whose speed in a vacuum is approximately
3 × 10
8 m/s
(186,000 miles/second)
Objective: Understand the wave equation
Warm-up Sketch and describe- give possible types of wavelength
A.
Electrocution
X-ray
B.
Sun burn UV
C. Radioactive
Gamma
D. No cell phones
Radio
\
Critical Thinking Wave Equation: v = λ ƒ
Horizontal line = Divide Vertical line = Multiply
Speed
Wav e leng th
Frequenc y
Wrap-up just practice the equation, the difference will be the values, like v = c from item #5
Units
Ex
λ= v / ƒ m
Find λ when v = 10m/s
ƒ = 5 Hz v = (10m/s) / (5Hz) or = (10m/s) / 5 (1/s)
= 2 m
ƒ = v / λ
Hz or 1/s
Find ƒ when v = 10m/s
λ = 5 m v = (10m/s) / (5m)
= 2 (1/s)
Or 2 Hz v = ƒ λ m/s
Find v when
ƒ = 10 1/s
λ = 5 m v = (10 1/s) (5m)
= 20 (m/s)

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.2 WCW
Topic: Electromagnetic Waves are all around Us
Standard:
PH 4. f. Students know how to identify the characteristic properties of waves: Interference (beats), Diffraction, Refraction,
Doppler Effect and Polarization
Objective: Understand the interactions of
Electromagnetic waves with each other and matter
Warm-up Sketch and describe- Why so Blue?
A. Blue bends the most
B. Blue bends the most
C. Blue bends the most
D. Blue reflects
Critical thinking
What is the main difference between Diffraction and refraction? Use item 7.7
Wrap-up Sketch and describe
A.
Waves have diff.
Energy
B.
Wavelengths, diff color
C.
Transverse wave
D.
Longitudinal wave

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.2 WCW
Topic: Electromagnetic Waves
Standard:
PH 4. f. Students know how to identify the characteristic properties of waves: Interference (beats), Diffraction,
Refraction,
Doppler Effect and Polarization
Objective: Understand the facts about the Electromagnetic spectrum
Warm-up
Give the wave type and describe the characteristics of that type for sound and light
Word bank-
Transverse Vacuum Medium (twice)
Longitudinal Parallel Perpendicular
Sound is _____1_____wave which is a wave that only travels through a________2________ because the displacement of the medium is_____3_____ to the propagation of the wave. Light is a _____4______wave which is a wave that can travel in both a
_____5______ and a _____6______this is because the displacement of the medium is ______7______to the propagation of the wave.
Critical thinking
Why is the wave said to be in a red shift or blue shift when describing
Doppler Effect?
Word bank- Away Red Toward Blue Frequency
The Doppler Effect is the change in pitch or ___1_____due to wave or object motion. If the object making the noise (or light) moves __2___ a stationary person then the sound (light) is heard (seen) as a __3___shift.
If the object making the noise (or light) moves ___4___ from a stationary person then the sound heard and light seen is said to be
___5__shifted.
Wrap-up one special direction Linearly- polarized un-polarized (3) Transverse always parallel Polarization perpendicular
_____________ is a property of light and of other transverse waves. _________________ waves are those in which the displacement of a test particle is always perpendicular to the direction in which the wave travels.
When that displacement is ___________________ to a particular direction, the wave is said to be
_____________________.
A ray of light emitted from a hot object, like a lamp filament or the sun, is unpolarized; such a ray consists of many component waves overlapped so that there is no special direction
_________________ to the ray in which a test particle is favored to move. The components of an
___________________ ray can be sorted to select such a special direction and so make one or more polarized rays. An _________________ ray that is partly reflected and partly transmitted by an angled sheet of glass is split into rays that are polarized; an ___________________ ray can become polarized by going through a material that allows only waves corresponding to ___________________________ to pass through.

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.4 vocabulary
1.
Index of Refraction . The ratio of the speed of a wave of a given frequency in a vacuum to its speed in a medium is called that medium’s. For visible light in water, this number is approximately 1.33.
2.
Constructive Interference the crest of one wave can overlap the crest of another, giving a larger displacement of the medium from its condition of equilibrium
3.
Destructive Interference the crest of one wave can overlap the trough of another, giving a smaller displacement;
4.
5.
6.
7.
8.
Nulls or Nodes a persistent pattern of having no displacement in some places
Maxima or Antinodes large, oscillating displacements in some places
Beats For sound waves this periodic change leads to audible, periodic changes from loud to soft,
Diffraction describes the constructive and destructive patterns of waves created at the edges of objects.
Refraction describes a change in the direction of a wave that occurs when the wave encounters a boundary between one medium and another provided that the media have either different wave velocities or indexes of refraction and provided that the wave arrives at some angle to the boundary other than perpendicular.
9.
Doppler Effect accounts for the shift in the frequency of a wave when a wave source and an observer are in motion relative to each other compared with when they are at relative rest.
10.
Polarization is a property of light and of other transverse waves.
11.
Transverse waves are those in which the displacement of a test particle is always perpendicular to the direction in which the wave travels.
12.
Linearly Polarized When displacement of a wave is always parallel to a particular direction. A ray of light emitted from a hot object, like a lamp filament or the sun, is un-polarized

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.5 Notes Electro-Magnetic Spectrum
Radio waves, light, and X-rays are different wavelength bands in the spectrum of electromagnetic waves whose speed in a vacuum is approximately 3 × 10
8 m/s (186,000 miles/second).
1.
Electromagnetic waves
 consist of changing electric and magnetic fields
 always perpendicular to the direction in which a wave moves, transverse wave
 perpendicular to each other
2.
Wavelength Range
Electromagnetic
Spectrum is very large: From Radio to
Gamma rays
3.
Visible Light
The human eye senses only a narrow range of the electromagnetic spectrum from 400 nm to 700 nm. This range generates colors

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Continue item #5
4.
Speed
In a vacuum all electromagnetic waves travel at the same speed
“Speed of light” c = 3 × 10
8 m/s 186,000 miles /s
UV light Can kill Tuberculosis bacteria. It must be at the same frequency as light with a wavelength of
254nanometers. Calculate the Frequency
C=f
λ
5.
In a medium the speed of an electromagnetic wave depends on the medium’s properties and on the frequency of the wave. Light frequency and wavelength changes in a material
6.
The ratio of the speed of a wave of a given frequency in a vacuum to its speed in a medium is called that medium’s index of refraction
Visible light in water,
Index of Refraction
Water = 1.33
Oil =1.47
Air = 1.0

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Properties of a wave:
– Wavelength- Lambda, λ units- m, meters
Peak to the next peak
Energy wavelength
Radio = 1000m = 10 3 m
Visible Light = between 400nm and 750nm
0.0000004 m = 400 x 10 -9 m = 400 nm
X-rays = 0.000000000001m = 10 -12 m
–
Amplitude - Amp or A units – m, meters
“Height” of the wave
– Frequency – ƒ units- Hertz, Hz or 1/s
Amount of wave passing a spot every second
1 Hertz = 1 Hz = 1 wave/second = 10 0 Hz
1 kilohertz = 1 kHz = 1000 Hz = 1 x10 3 Hz
1 megahertz = 1 million Hz = 1 x 10 6 Hz
Using the ‘wave equation’:
–
v= ƒ λ or c = ƒ λ c = 3 x 10 8 m/s
Vacuum -outer space
Speed of all EM waves = 300 million m/s
General
Speed (m/s) = frequency (Hz) x wavelength (m)
The EM spectrum:
–
Different regions which depend on the properties of the EM spectra
–
R-M-I-V-U-X-G
– Electrical and magnetic disturbances that transfer energy
All travel at speed of light
–
Energy transferred by wavelength
–
Put into groups according to wavelength
– Different waves lengths = different effects

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Notes:
1.
Electromagnetic waves-Radio, TV, Microwave, Infrared,
Visible light, Ultra-Violet, X-ray, Gamma ray
2.
Interference- the superposition of two or more waves resulting in a new wave pattern
3.
Constructive interference- two waves that are in phase, sharing the same frequency and with amplitudes A
1
and A
2
.
Their troughs and peaks line up and the resultant wave will have amplitude A = A
1
+ A
2
.
4.
Destructive interference- two waves are π radians, or 180°, out of phase, then one wave's crests will coincide with another waves' troughs and so will tend to cancel itself out. The resultant amplitude is A = |A
1
− A
2
|. If A
1
= A
2
, the resultant amplitude will be zero.
5.
Node- minimum in the electromagnetic wave
6.
Antinode- maximum in the electromagnetic wave
7.
Diffraction- the apparent bending of waves around small obstacles and the spreading out of waves past small openings.
8.
Refraction- change in direction of a wave due to a change in its speed
9.
Doppler Effect- the change in frequency of a wave for an observer moving relative to the source of the wave
10.
Polarization- the orientation of oscillations in the plane perpendicular to a transverse wave's direction of travel

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.6 Problems EM waves
3
-10

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7. 7 Notes IDRDP
Interference
• Constructive- adding waves makes bigger wave
• Destructive- adding waves makes smaller wave
Diffraction- bending pattern of light around material
Refraction-bending of light through material
Reflection- Mirror image of an object
Doppler Effect- red, lower frequency, away
-blue, higher frequency, toward
Polarization- the orientation of the oscillation in a wave is perpendicular to motion (rollercoaster)

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.8 Problems Properties of IDRDP
1.
Reflection occurs when a wave __________
A) causes ripples in a pool of water
B) compresses air particles as it travels
C) strikes an object and bounces off of it
D) bends and changes speeds as it travels
2.
The __________ is an imaginary line perpendicular to the surface of a medium where a wave strikes it.
A) incidence
B) diffraction grating
C) interference
D) normal
3.
__________ occurs when waves bend around a barrier.
A) Reflection
B) Refraction
C) Interference
D) Diffraction
4.
Why can't you see your reflection in a brick wall?
A) Light rays are reflected in only one direction from the rough surface.
B) Reflection of light from a rough surface is regular reflection.
C) No light is reflected from a brick wall.
D) Light rays are reflected in many directions from the uneven surface.
5.
The bending of a light wave as it moves from one medium into another is called __________
6.
Which of the following is true?
A) You can hear sounds from a room you haven't entered because of the refraction of sound waves.
B) You can see into a room that is around a corner because of the extensive diffraction of light waves.
C) You can hear sounds from a room you haven't entered because of the diffraction of sound waves.
D) You can see into a room that is around a corner because of the refraction of light waves.
7.
The process in which two waves overlap and form a new wave is called __________
A) wave joining
B) refraction
C) interference
D) diffraction
8.
__________ occurs when the crest of one wave overlaps the trough of another wave.
A) Constructive interference
B) Wave cancellation
C) Amplitude shift interference
D) Destructive interference
9.
__________ occurs when the crest of one wave overlaps the crest of another wave.
A) reflection
B) diffraction grating
C) interference
D) refraction
D) Diffraction
A) Destructive interference
B) Constructive interference
C) Rarefaction

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
10.
Polarization of light is described by the …
A.
Parallel motion to the wave's direction of travel
B.
Perpendicular motion to the wave's direction of travel
11.
The shift to larger wavelengths by motion away from the observer is called a ____shift
A Red B Blue
12.
The shift to shorter wavelengths caused by motion toward the observer is called a ____ shift .
A Red B Blue
Circle correct response
13.
Reflection occurs when a wave strikes an object and _______ (transmits or bounces) off of it
14.
The normal is an imaginary line ______(parallel or perpendicular) to the surface of a medium where a wave strikes it.
15.
Diffraction occurs when waves bend _________
(through or around) a barrier.
16.
Why can't you see your reflection in a brick wall?
Light rays are reflected in ______ (many or few) directions from the uneven surface.
17.
18.
The Doppler effect occurs for ____ wavelengths of light, not just the visible spectrum
A.
A All B A certain
The direction of light propagation can be changed at the boundary of two media having different densities. This property is called ____________
B.
A Diffraction B Refraction
19.
Because light is a wave, it has the capability to "bend around corners", ____________
C.
A Diffraction B Refraction
Circle correct response
20.
The bending of a light wave as it moves from one medium _____ (off or into) another is called refraction
21.
You can hear sounds from a room you haven't entered because of the __________ (refraction or diffraction) of sound waves.
22.
The process in which two waves _______
(overlap or miss) and form a new wave is called interference
23.
Destructive interference occurs when the crest of one wave overlaps the_____ ( crest or trough) of another wave.
24.
Constructive interference occurs when the crest of one wave overlaps the _____ ( crest or trough) of another wave.

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.9 Studyguide

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Item 7.10 ICS 1 Block 7 CST PREP Wave Properties
Order the Electromagnetic wave types by wavelength, largest to smallest :
Gamma, Radio, Visible, Radio, Ultra-Violet, Microwave, X-ray, Infrared
_________,___________,__________,__________,__________,__________,_________
1.
2.
3.
4.
5.
6.
7.
8.
9.
______Interference
______Constructive interference
______Destructive interference
______Node
______Antinode
______Diffraction
______Refraction
______Doppler Effect
______Polarization a) Maximum in the electromagnetic wave b) The orientation of oscillations in the plane perpendicular to a transverse wave's direction of travel c) Change in direction of a wave due to a change in its speed d) Two waves that are in phase, sharing the same frequency and with amplitudes A
1
and A
2
. Their troughs and peaks line up and the resultant wave will have amplitude A = A
1
+ A
2
. e) The superposition of two or more waves resulting in a new wave pattern f) The apparent bending of waves around small obstacles and the spreading out of waves past small openings g) Minimum in the electromagnetic wave h)
Two waves are π radians, or 180°, out of phase, then one wave's crests will coincide with another waves' troughs and so will tend to cancel itself out. The resultant amplitude is A = | A
1
− A
2
|. If A
1
=
A
2
, the resultant amplitude will be zero. i) The change in frequency of a wave for an observer moving relative to the source of the wave
Phy 4.a
59. A sound wave is produced in a metal cylinder by striking one end. Which of the following occurs as the wave travels along the cylinder?
A Its amplitude increases B Its frequency increases C It transfers matter D It transfers energy
60. The graph below depicts the relationship between wave energy and wave amplitude.
Energy - kilojoules
60
How is the energy of the wave affected if the amplitude of the wave increases
50
40 from 2 meters to 4 meters?
A It is halved
30
20
Energy kilojoules
B It is doubled
C It is quadrupled
D It remains the same.
10
0
0 2 4 6

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f
Phy 4.b
61. A radio station transmits to a receiving antenna. The radio wave sent is a
A sound wave
B torsional wave
C longitudinal wave
D transverse wave
62. A stretched spring attached to two fixed points is compressed on one end and released, as shown below. The resulting wave travels back and forth between the two fixed ends of the spring until it comes to a stop. This mechanical wave is an example of a
A transverse wave
B longitudinal wave
C superposition wave
D refracted wave
63 One end of a horizontal string is caused to oscillate vertically while the other end is attached to a fixed object. The wave that travels along the string is an example of
A an electromagnetic wave B a transverse wave
C a microwave D a longitudinal wave
Phy 4.d
69. Sound waves cannot carry energy through
A water B air
C a mirror D a vacuum
Ph 4.e
70 Where does visible light fall on the electromagnetic spectrum?
A between x-rays and gamma rays
B between short-wave radio and television
C between infrared and ultraviolet
D between microwaves and infrared
71. In a vacuum, radio waves, visible light, and x-rays all have the same
A wavelength
B speed
C frequency
D energy
Ph 4.f
72 Objects appear different in size and shape in a container of water due to
A refraction of the light waves
B interference of the water and light waves
C polarization of the light waves
D diffraction of the light waves
73 An engineer in a moving train blows the train’s horn. The train is moving away from a person standing on the ground. Compared to the frequency of the sound that the engineer hears, the person standing on the ground hears a sound with
A the same wavelength
B more variation in tone
C greater amplitude
D a lower frequency

ICS 1 Sem1 Block 7 Light Standards Physics 4 e, f