Module Code: PASAY-S11/12-PS-S2-Q2-W5-D1
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
DEPARTMENT OF EDUCATION- NATIONAL CAPITAL REGION
SCHOOLS DIVISION OF PASAY CITY
MODULE IN PHYSICAL SCIENCE 12
SECOND SEMESTER / QUARTER 2/ WEEK 5/ DAY 1
VAROIUS LIGHT PHENOMENA
PURPOSE OF THIS MODULE
At the end of this module, you will be able to explain why your reflection on the
concave and convex sides of a spoon looks different.
INTRODUCTION
In the previous lesson, you knew that light reflects or bounce back as it hits an opaque object
such as mirror and transmitted through transparent objects such as glass and lenses. Light refracts or
bend as it enters from one medium to another with different optical density. You also knew that the
colors we see on the object is the color of light that is reflected by the object to our eyes. The green color
of the leaves is the due to the green light that is reflected by the leaves to our eyes, and all the other
color of light is absorbed and only the green is reflected.
These behaviors of light produce spectacular light phenomena that we often see in our daily life
and sometimes we may not notice it.
.
ACTIVITY 1. Spoon In and Spoon Out1
In this experiment, you will be able to see how you look when you look at the concave and
convex sides of a spoon. Write your observations on a separate sheet of paper.
1. Stand in a well-lit room or outside. Hold the spoon by the handle just like you would
when you are eating but flip it over so that the back of the spoon is facing you. Look at yourself
in the curved end, what do you look like?
2. Now turn the spoon so that the back of the spoon is still facing you but the curved part
is pointing at the ceiling or sky. Have another look at yourself.
3. Next, turn the spoon over and look at yourself in the front of the curved part where the
food normally goes. What do you see?
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D1
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
Activity 1. 1 . Spoon in and Spoon Out
Concave
Convex
The shiny spoon is like a mini mirror, but with a curve in it. The front of the spoon is a
CONCAVE surface, and the back is a CONVEX surface.
1 Monster Sciences, “Activity 1: Changing Colour.”
Ray Diagram of Concave Mirrors in a Spoon 3
In the center of the sphere from which the mirror was sliced is known as the center of
curvature and is denoted by the letter C in the diagram below. The point on the mirror's
surface where the principal axis meets the mirror is known as the vertex and is denoted by
the letter A in the diagram below. The vertex is the geometric center of the mirror. Midway
between the vertex and the center of curvature is a point known as the focal point; the focal
point is denoted by the letter F in the diagram below.
The distance from the vertex to the center of curvature is known as the radius of curvature
(represented by R). The radius of curvature is the radius of the sphere from which the mirror
was cut. Finally, the distance from the mirror to the focal point is known as the focal length
(represented by f).
Since the focal point is the midpoint of the line segment adjoining the vertex and the center of
curvature, the focal length would be one-half the radius of curvature
3
The Physics Classroom. “The Anatomy of a Curved Mirror.”
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D1
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
Ray Diagram of Convex Mirrors in a Spoon 4
The diagram at the right depicts a convex mirror. In Lesson 3, a convex mirror was described as
a portion of a sphere that had been sliced away. If the outside of the sphere is silvered such that
it can reflect light, then the mirror is said to be convex. The center of that original sphere is
known as the center of curvature (C) and the line that passes from the mirror's surface through
the sphere's center is known as the principal axis. The mirror has a focal point (F) that is located
along the principal axis, midway between the mirror's surface and the center of curvature. Note
that the center of curvature and the focal point are located on the side of the mirror opposite the
object - behind the mirror. Since the focal point is located behind the convex mirror, such a
mirror is said to have a negative focal length value.
A convex mirror is sometimes referred to as a diverging mirror due to the fact that incident light
originating from the same point and will reflect off the mirror surface and diverge. The diagram
at the right shows four incident rays originating from a point and incident towards a convex
mirror. These four rays will each reflect according to the law of reflection. After reflection, the
light rays diverge; subsequently they will never intersect on the object side of the mirror. For this
reason, convex mirrors produce virtual images that are located somewhere behind the mirror.
The image in the diagram above is a virtual image. Light does not actually pass through the
image location. It only appears to observers as though all the reflected light from each part of
the object is diverging from this virtual image location. The fact that all the reflected light from
the object appears to diverge from this location in space means that any observer would view a
replica or reproduction when sighting along a line at this location.
4
The Physics Classroom. “Reflection and Image Formation for Convex Mirrors.”
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D1
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
EVALUATION:
For numbers 1 to 5, use the following choices:
A. concave side
B. convex side
C. TRUE
D. FALSE
______1. A spoon is a double mirror.
______2. The reflection in a spoon changes as you go near to it.
______3. Both sides of a spoon can give different image orientations.
______4. This side of the spoon gives you an upright reflected image.
______5. This side of the spoon gives you an inverted reflected image.
___ _ _6. Convex mirrors produce_______
A. only virtual images
C. virtual or real images
B. only real images
D. inverted images
______7. Concave mirrors can create virtual and real images.
A. True
B. False
______8. Plane mirrors create real images.
A. True
B. False
______9. What does the Law of Reflection state?
A. the angle of the incident ray makes with a line drawn perpendicular to the surface of
the mirror.
B. the angle of reflection is equal to the angle of incidence.
C. shows how rays change direction when they strike mirrors and pass-through lenses.
D. none of the above
_____10. If the angle of incidence is 60 degrees from the normal line, what is the angle of
reflection and the total angle between the incident and reflected ray?
A. Angle of reflection = 30 degrees
Total angle = 90 degrees
B. Angle of reflection = 30 degrees
Total angle = 120 degrees
C. Angle of reflection = 60 degrees
Total angle = 90 degrees
D. Angle of reflection = 60 degrees
Total angle = 120 degrees
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D1
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
_____11. What is the name of the perpendicular line that we use to measure angles in
reflection?
A. incident ray
B. normal
C. reflected ray
D. source ray
_____12. A shinny spoon can create_________
A. erect image
C. inverted image
B. both erect and inverted images D. neither inverted not erect image
_____13. The focal length is equal to the _______
A. radius of curvature
B. half radius of the curvature
C. diameter of curvature
D. half diameter of curvature
_____14. The inside of the spoon is same as_______
A. concave mirror
C. convex mirror
B. plane mirror
D. none of these
_____15. An erect and enlarged image can be formed by___
A. only a convex mirror.
B. only a concave mirror.
C. only a plane mirror
D. both convex and concave
____________________________________________________________________________
___________________
References for further enhancement:
General Physics 2 by Helen E. Caintic
https://quizizz.com/admin/quiz/585a9152c851deeb33b5ca25/mirror-quiz _
https://ncert.nic.in/pdf/publication/exemplarproblem/classVII/Science/geep115.pdf _ Project
EASE Physics Module 3: The Nature and Properties of Light
https://lrmds.deped.gov.ph/detail/6710
____________________________________________________________________________
__________
Danilo S. Lagman
Pasay City South High School
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D2
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
DEPARTMENT OF EDUCATION- NATIONAL CAPITAL REGION
SCHOOLS DIVISION OF PASAY CITY
MODULE IN PHYSICAL SCIENCE 12
SECOND SEMESTER / QUARTER 2/ WEEK 5/ DAY 1
THE FORMATION OF MIRAGE
PURPOSE OF THIS MODULE:
✓ EXPLAIN HOW MIRAGES ARE FORMED
MAIN IDEA: A mirage is an optical
phenomenon resulted from the refraction of light
rays through the layers of air of varying temperature
and density.
EQ: Where do mirages come from?
Sky
MIRAGE!!!
pool of water
Did you know that the words “mirage” and
“mirror” are derived from the same root
word, which means “to look at”. –
Kidzsearch, 2020
Imagine that a traveler is wandering in the dessert.
He’s been walking for hours and has run out of
water. At the far end of the desert he saw a pool of
water, so he quickly ran towards it and found out
nothing but sand. What do you think happened to
the pool of water? Was the traveler experienced
hallucination?
The ‘pool of water’ saw by the traveler is not
produced out of his hallucination, but it is a product
of an optical illusion known as mirage.
Desert
Figure 1. An example of mirage in the desert.
I. How do mirages form?
Mirage is a deceptive appearance of a distant image or
object that is formed due to the refraction of light
(Kidzsearch, 2020; The Physics Classroom, 2021). It may look
weird, but it really exists in reality. To better understand
the formation of mirage, we need to learn first why light is
refracted in the air.
A
B
C
When a light ray from the sun passes through
atmosphere (layers of air) with even density and
temperature, it travels in a straight path which is then
Figure 2. The path of light rays across the varying density
reflected from the object (Camel in Figure 2) and goes into
of air.
our eyes. Consequently, we see the object where it is (see
Figure 2A). However, if the light passes across layers of air that are different in temperature and density, the
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D2
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
light will travel at different speeds causing it to refract or bend (see Figure 2B). As a result, we no longer see the
object clearly or where it really is, or in other words we see its mirage (see Figure 2C) (Windy.app, 2021; Encyclopedia
Britannica, 2021; Scientific American, 2021; Planet Science, 2010).
Mirage usually happens during hot,
sunny days where intense sunshine (sun’s
energy) is absorbed by the ground. During these
conditions, the layer of air closest to the ground
is hottest and least dense, while the air above it
rapidly cools and is denser. You learned that
light consists of photons (sun’s energy) and
these photons move faster through warm air as
it is less dense than cold air, following a curved
path from the sky to the viewer’s eye. Figure 3
shows that when light travels through the cold air
and into the layer of hot air, it is refracted (or
bent) (Windy.app, 2021; Encyclopedia Britannica, 2021).
Another property of light that we need to
understand
in the formation of mirage is
Figure 3. The mirage of sky as a ‘lake’ or ‘pool of water’.
reflection. The camel (Figure 2A) is seen as is
because the reflected ray enters the viewer’s eye in a straight line without being refracted through the cool air,
but it curves upward after it enters the layer of hot air causing it to be refracted to the viewer’s eyes as though
it originated below the heated ground (Figure 2B and C). Do you remember the ‘pool of water’ seen by the
traveler in our first example? It was actually the sky. The light from the sky is being refracted by the layer of
very warm air near the ground. Unfortunately, our brain thinks the light must have come from something on the
ground. Therefore we mistakenly view the land as a lake or a pool of water (Figure 3) (Scientific American, 2021;
Planet Science, 2010).
PRACTICE EXERCISES 1
Directions: Cite an instance where you observed a mirage. Draw it inside the box and briefly explain
how the mirage occurred in that place.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D2
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
II. Kinds of Mirage
There are three kinds of mirage formation: Inferior, Superior, and Fata Morgana.
A. Inferior Mirage
Inferior mirage is the very common kind of mirage,
which commonly occurs in very hot areas such as
desert. The mirage of objects are seen below (inferior)
their actual location due to refraction of light as it
passes through the cold air and hot layer of air at the
surface of the ground. Figures 2, 3 and 4 are examples
of inferior mirages. The reflection of sky is also an
example of inferior mirage, which gives us the illusion
of ‘pool of water’ or lake (Windy.app, 2021).
Figure 4. The formation of an inferior image (inferior mirage).
B. Superior Mirage
a
b
Figure 5. A. The formation of a superior image (superior mirage); B. Superior mirage of an ordinary barge on the sea.
Superior mirage, also known as looming phenomenon, is the opposite of inferior mirage and are less common.
This kind of mirage usually happens in cold regions. The mirage of objects are seen above (superior) their actual location
due to the ground or surface that is much colder than the air above it. Superior mirage changes more slowly and does
not disappear quickly, which makes it more stable than inferior mirages. It also enable us to see objects or images that
are far beyond the horizon. Take for example the images in Figure 5. Figure 5a shows that the boat is seemingly observed
lifted into the sky, while Figure 5b shows a superior mirage of an ordinary barge that is apparently looks like a very huge
ship hovering the sea (Windy.app, 2021; Encyclopedia Britannica, 2021).
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D2
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
C. Fata Morgana
a
b
c
Figure 6. Fata Morgana (mirages): a and b distorted images seen at the sea; c distorted image of rocks.
Fata morgana is the third type of mirage. This is an unusual and has a seldom appearance among the three kinds.
The mirage forms when light rays pass across many layers of air with alternate sharply in temperature, or there
is a steep thermal inversion in the layers of air. Fata morgan often produced very distorted objects which are
completely unrecognizable, thereby creating the most bizarre images. It can be seen anywhere such as on land or at sea,
in polar regions or in deserts. Compared to inferior and superior mirages, fata morgana changes constantly and can
disappear instantly. Figure 6 shows images of fata morgana seen over the sea ( refer to white arrows) (Windy.app, 2021).
PRACTICE EXERCISES 2
Directions: Using the Venn diagram, compare the three kinds of mirage.
Superior Mirage
Inferior Mirage
Fata Morgana
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D2
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
GENERALIZATION
Mirage is an optical phenomenon resulted from the refraction of light rays
through the layers of air of varying temperature and density, which often produced
distorted objects or images. There are three kinds of mirages: inferior, superior and
fata morgana.
EVALUATION
MULTIPLE CHOICE
DIRECTIONS: Encircle the letter of your answer.
1. What properties of light often cause the formation of a mirage?
A. reflection and refraction
B. reflection and interference
C. interference and refraction
D. reflection, refraction and interference
2. What happens to the ray of light when travelling across the layers of air of varying temperature
and density?
A. It reflects.
B. It refracts.
C. It bounces.
D. It disappears.
3. Which condition(s) often result(s) to the formation of an inferior mirage?
A. The ground or surface is very hot which cools the air above it.
B. The ground or surface is very cold which cools the air above it.
C. The ground or surface is very hot which warms the air above it.
D. The ground or surface is very cold which warms the air above it.
4. Which kind of mirage produced due to steep thermal inversion of the layers of air?
A. Inferior
B. Looming
C. Superior
D. Fata Morgana
5. Which kind of mirage is the most stable and do not disappear quickly?
A. Inferior
B. Looming
C. Superior
D. Fata Morgana
Writer:
MR. JOEMAR D, MARTINEZ
Pres. Corazon C. Aquino National High School-SHS
References:
*Encyclopedia Britannica. (2021). Mirage. Retrieved from https://www.britannica.com/topic/mirage-optical-illusion
on May 9, 2021.
*KidzSearch. (2020). Mirage. Retrieved from https://wiki.kidzsearch.com/wiki/Mirage on May 5, 2021.
*Planet Science. (2010). What is a mirage?. Retrieved from http://www.planet-science.com/categories/under-11s/ourworld/2012/01/what-is-a-mirage.aspx on May 9, 2021.
*Scientific
American.
(2021).
What
causes
a
mirage?.
Retrieved
from
https://www.scientificamerican.com/article/what-causes-a-mirage/ on May 9, 2021.
*The Physics Classroom. Mirages. Retrieved from https://www.physicsclassroom.com/class/refrn/Lesson-4/Mirages
on May 9, 2021.
*Windy.app. Where Do Mirages Come From?. Retrieved from https://windy.app/textbook/where-do-mirages-comefrom.html on May 9, 2021.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D3
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
DEPARTMENT OF EDUCATION- NATIONAL CAPITAL REGION
SCHOOLS DIVISION OF PASAY CITY
MODULE IN PHYSICAL SCIENCE 12
SECOND SEMESTER / QUARTER 2/ WEEK 5/ DAY 3
MONOCHROMATIC LIGHT’S BEHAVIOR
The purpose of this module is to explain monochromatic light’s
behavior when projected on different colors of cellophane; and why
colored clothes appear differently when exposed to sunlight and
artificial light.
What is Monochromatic Light?
Monochromatic light is light (optical radiation) where the optical spectrum contains only
a single optical frequency. Light exhibits certain behaviors that are characteristic of any wave.
Such a pattern is only noticeable in a narrow beam of monochromatic light.
Sunlight is a combination of seven colors, which means that there are seven
different light waves with different wavelengths all mixed to give perception of single
color. Monochromatic means "same color". This light which has same wavelength will show
only a single color and this light will be monochromatic.
The color of the sun is white. The sun emits all colors of the rainbow more or less evenly
and in physics, we call this combination "white". That is why we can see so many different colors
in the natural world under the illumination of sunlight. White light consists of different colors
of light with different wavelength. Thus, it is a polychromatic light, not a monochromatic light.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D3
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
How is Monochromatic Light produce?
Monochromatic light, or one-color light, is essentially electromagnetic radiation
derived from photon emissions from atoms. Photons propagate, or travel, as energy wave fronts
of different lengths and levels of energy. Energy levels determine the frequency of light, and the
length of a wave determines its color.
How Monochromatic Light Behave?
Light, just like any electromagnetic wave, carries energy proportional to its frequency.
Upon encountering an object, light may transfer all or some of its energy. Object that absorbs
incident lights or any electromagnetic wave are considered opaque to that particular wave.
Objects that allow an electromagnetic wave to pass through them are transparent to that
particular wave.
Some opaque objects absorb only specific wavelengths of light and reflect others.
For example, a red apple appears red when illuminated with white light. It reflects only the red
component of white light and absorbs the other colors.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D3
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
A transparent material selectively absorbs one or more frequencies of light and
transmits what is not absorbed. The color of a transparent material is the color of the light it
transmits. This explains why light from a red laser passes more easily through red cellophane
than green cellophane.
Light passes through green cellophane
Light passes through red cellophane
The
value
and
intensity
of
a color affected
by
the
amount
of light,
too.
In
lower light, colors appear darker and less intense. As you increase the amount of light, the value
lightens, and the intensity increases until you reach its true color.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D3
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
PRACTICE EXERCISE NO.1
DIRECTIONS: Supply the spaces with appropriate terminologies.
The _____ colors of light are red, ____and ________. If equal intensities of these colors
shone on a spot, the spot would be _______. All other colors produced by mixing suitable
portions called ________ colors.
PRACTICE EXERCISE NO.2
DIRECTIONS: Identify the result of two colors combined.
Red +
Blue =
Red +
Green =
Blue +
Green =
Blue +
Yellow =
Red +
Yellow =
PRACTICE EXERCISE NO.3
DIRECTIONS: Explain the following situations.
1. What will happen if red umbrella illuminated with blue light?
_______________________________________________
2. What will happen if red carpet illuminated with yellow light?
_______________________________________________
GENERALIZATION:
Different
colors of light have different frequencies,
which
causes
them
to
travel
at different speeds when they move through matter. A color that travels more slowly in glass will
bend more sharply when it passes from air to glass, because the speed difference is more
severe.
Objects appear in different colors because some colors (wavelengths) are absorb and reflected
or transmit other colors. The colors seen are the wavelengths reflected or transmitted. White
objects appear white because they reflect all colors. Black objects absorb all colors no light is
reflected.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D3
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
EVALUATION:
DIRECTIONS: Read the questions carefully and answer it correctly.,
A. What would be the color of a yellow object when illuminated with
1.
2.
3.
4.
5.
White light?
Green light?
Red light?
Blue light?
Is white light be produced by mixing all the primary colors of pigments in equal proportions?
B. Classify if the statement is Fact or Bluff.
6. Colors of light have the same frequencies and travel at different speed.
7. White objects appears black because all colors are absorb.
8. Monochromatic light has same wavelength and show only a single color.
9. Objects that allow an electromagnetic wave to pass through them are opaque.
10. As the amount of light increase, the value lightens and the intensity increases until
you reach its true color.
REFERENCES:
Exploring Life through Science Series Physical Science
KAREN S. SANTIAGO/ANGELINA A. SILVERIO
PREPARED BY:
ROSEMINDA K. TAPONG
KALAYAAN NATIONAL HIGH SCHOOL
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D4
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
DEPARTMENT OF EDUCATION- NATIONAL CAPITAL REGION
SCHOOLS DIVISION OF PASAY CITY
MODULE IN PHYSICAL SCIENCE 12
SECOND SEMESTER / QUARTER 2/ WEEK 5/ DAY 4
Optical Phenomena
What i need to know?
What to
know
Explain the formation of haloes, sundogs, primary rainbows, secondary
rainbows, and supernumerary bows, blue sky, red sunsets, white and dark
clouds, and other OPTICAL PHENOMENA.
An Aurora, sometimes referred to as polar lights,
northern lights, or southern lights, is a natural light
display in the Earth's sky, predominantly seen in highlatitude regions. Auroras are the result of disturbances
in the magnetosphere caused by solar wind.
BASIC CHARACTERISTICS OF LIGHT
Before we start studying the different phenomena of light, we need to enumerate some of the basic
principles we know regarding the nature of light: 1. Light travels in a straight line and called ray. 2. Light Travels
at high speed, 3x10^8 m/s in vacuum. 3. A collection of rays of light is called a BEAM, and can be parallel,
diverging, and converging. 4. Visible light consists of SIX colors, from red having the lowest frequency to violet
with the highest frequency. 5. Light has no mass but carries energy and momentum, and 6. Light is in the form
of QUANTA (photons) but propagated in the form of waves.
TOPIC FOR TODAY
Optical phenomena are any observable events that result from the interaction of light and matter. We
will explain the scientific principles behind haloes, sundogs, rainbows, secondary rainbows, mirages, light pillars,
twilight, sunrise, sunsets, dark and white clouds. We will also appreciate the eccentric nature of light and try to
spot out any optical phenomena when we see one of them.
Mental exercise. This CROSSWORD and
IDENTIFICATION ACTIVITY will help you
know the terms you need to better understand
the lesson. Find the answers on the next pages
while reading you modules
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D4
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
Explanations Behind Different Optical Phenomena
1. 1. HALOES:
Solar halo, which is also called gloriole, is a light phenomenon
that happens when light shines through clouds that are
composed of ice crystals. The refraction of light upon passing
through the ice crystals and also the reflection upon hitting the
crystal’s faces is the reason behind this. These events cause the
formation of the bright ring around the Sun or Moon. Halo is
usually bright white ring but may also have colors due to the
dispersion of light upon striking the ice crystals.
When does a Halo occur?
• When the climate is cold, and ice crystals are present in
the CIRRUS clouds.
• The same thin clouds can cause a ring, or halo, around the
moon at night.
2. SUNDOGS
Sundogs, or parhelion, happen due to the bending of light
upon striking the minute crystals that make up cirrus or
cirrostratus clouds. These crystals are hexagonal in shape
and with faces almost horizontal; these cause the formation
of spots of light (sundog) when light strikes them at a
minimum angle of 22 degrees. Since red light is the least
refracted compared to blue this makes the inner edge of a
sundog to be red hued.
•
•
When does a sundog occur?
At any time of the year and from any place, although they
are most visible when the sun is lower on the horizon in
January, April, August and October
when ice crystals in the atmosphere are more common, but
can be seen whenever and wherever there are cirrus clouds
3. RAINBOWS
A rainbow is a light phenomenon formed from the
combination of refraction, reflection, and dispersion.
Rainbows are usually seen after rainfall light strikes the
scattered water vapor in the atmosphere.
Light is refracted upon hitting a raindrop that serves as the
prism. The colors reflect upon hitting the other side of the
raindrop and then refracted again as they go out.
When does a Rainbow Happen?
Name: ________________________________ Grade & Section: ______________________
• The most familiar type rainbow is produced when sunlight
Name strikes
of Teacher:
_______________________
Strand: angle
_______________________________
raindrops
in front of a viewer at a precise
(42
•
degrees).
Rainbows can also be viewed around fog, sea spray, or
waterfalls.
4. SECONDARY RAINBOW
During such good visibility conditions, the larger but fainter
secondary rainbow is often visible. It appears about 10°
outside of the primary rainbow, with inverse order of colors.
Secondary rainbows are caused by DOUBLE
REFLECTION of light inside water droplets
When does a Secondary Rainbow Happen?
• When light entering a raindrop undergoes two internal
reflections instead of just one
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D4
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
5. MIRAGE
It is an optical phenomenon that creates the illusion of water/
other images and results from the refraction of light through
a non-uniform medium. Mirages are most commonly
observed on hot days when driving down a roadway.
Because of the hot and cold air mixing on the surface, it
becomes uniform and thus refracts light, making it appear to
have an inverted image.
•
When does a mirage happen?
Mirages happen when the ground is very hot and the air is
cool. The hot ground warms a layer of air just above the
ground. When the light moves through the cold air and into
the layer of hot air it is refracted (bent)
6. LIGHT PILLAR
A visual phenomenon created by the reflection of light from
ice crystals with near horizontal parallel planar surfaces. The
light can come from the Sun (usually at or low to the horizon)
in which case the phenomenon is called a sun pillar or solar
pillar. It can also come from the Moon or from terrestrial
sources such as streetlights.
•
When does a LIGHT PILLAR occur?
When sunlight (or any light source) strikes suspended ice
crystals and reflects off their surfaces. Ice crystals are
associated with thin, high-level clouds.
7. TWILIGHT, SUNRISE, SUNSET,
TWILIGHT happens when the sun is below the horizon, but
its light is scattered (refracting red and orange) enough to
give light even when the sun sets. Twilight is produced by
sunlight scattering in the upper atmosphere, illuminating the
lower atmosphere so that Earth's surface is neither
completely lit nor completely dark. This also explains why
SUNSETS are yellowish and reddish in color, and SUNRISE
is usually blue because the scattering of light when the sun is
rising is usually high in frequency (blue-violet)
TWILIGHT, SUNRISE, SUNSET, CLOUD COLORS
•
•
•
When do they occur?
TWILIGHT – period between sunset and dusk (evening), and
sunrise and day
SUNRISE – when sun is approaching the horizon
SUNSET – when sun is leaving the horizon
8. CLOUD COLORS
The color of clouds depends on the color/s of light they
receive. The Earth's natural source of light is the sun which
provides 'white' light. The colors change as the wavelength
increases from violet to indigo to blue (sunrise), green (rare),
yellow, orange, red and deep red (sunset).
Dark clouds are because of the substances like smoke, water
vapor, and other gases absorbing the light, making it reflect
less color and look “dark”. The dark color is generally
because of its absorption of light.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D4
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
EXERCISE 1 : Identify the optical phenomena being illustrated in the following pictures
`
EXERCISE 2 : Modified True or False. Write the word TRUE if the statement is correct and if NOT,
change the underlined word or that makes the sentence false.
1. Haloes occur when the climate is COLD. __________
2. NIMBUS clouds are the types of clouds that can produce sundogs or haloes. _______
3. Light pillars occur when light strikes suspended ice crystals and REFRACTS their surfaces
________
4. TWILIGHT is the period between SUNRISE and dusk. _________
5. The dark color of clouds is generally because of its REFLECTION of light. ________
EVALUATION: Encircle the letter of the best answer for each item.
1. What light phenomenon is seen usually after a rain shower when the atmosphere is filled with tiny
droplets of water?
A. sundog
B. halo
C. mirage
D. rainbow
2. Which of the following correctly describes how a halo looks like?
A. Bright ring formed around the sun or moon.
B. Bright spots of light formed in either side of the sun or moon.
C. An arc of colors that forms opposite the sun.
D. An arc of light composed of green, pink and purple colors.
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Module Code: PASAY-S11/12-PS-S2-Q2-W5-D4
Name: ____________________________________________________ Track/Strand: _______________
Teacher: ___________________________________________________ Grade Level: _______________
3. In the formation of sundogs, how should the ice crystals (which light strikes at an angle 22
degrees) be oriented as they drift?
A. The ice crystals are oriented vertically.
B. The ice crystals are oriented horizontally.
C. The ice crystals are oriented diagonally to the right.
D. The ice crystals are oriented diagonally to the left.
4. What optical phenomena creates the illusion of water/ other images and results from the refraction
of light through a non-uniform medium?
A. sundog
B. halo
C. mirage
D. rainbow
5. What optical phenomena happens due to the bending of light upon striking the minute crystals that
make up cirrus or cirrostratus clouds
A. sundog
B. halo
C. mirage
D. rainbow
SUMMARY:
❖ Optical phenomena are any observable events that result from the interaction of light and matter.
These are sundogs, haloes, rainbows, mirages, light pillars, and twilight
❖ These optical phenomena happen because of the nature of light, having different frequencies and
wavelength, being able to reflect, disperse, become absorbed, and refracted.
❖ Different optical phenomena happen because of the formation of ice crystals, water vapor, hot and cold
weather, and the position of the sun relative to the atmosphere and horizon.
❖ Colors of the clouds, twilight, sunset and sunrise are because of the absorption, reflection, and refraction
of light in the atmosphere.
Writer: GIAN DEL N. ATALIA
School: Pasay City North High School – Tramo Campus
References:
1.https://studylib.net/notes/physical-science/810-light-phenomena-ii/3390814950934706/
2. http://astronomy.nmsu.edu/kurt/Astronomy110G/Lectures/12.Light&Matter.pdf
3. https://www.physicsclassroom.com/class/refrn/Lesson-4/Mirages
4.https://www.slideshare.net/MeganLeigh12/optical-phenomena-final 5.
5. https://www.spc.noaa.gov/publications/corfidi/sunset/
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