My Way Science Health and Physical Education 5

c. List the things that are in the solid form but we C
make them liquid while preparing our food. K
A
d. What is condensation ?
e. What are the processes of change of state of substances ?
f. Differentiate between:
i. Melting and freezing
ii. Evaporation and condensation

My way of doing science Ap

Take a kettle of water and a metal plate. Boil the water on
the stove. You will see the water vapor coming out from
the kettle. Now put the metal plate above the mouth. You
will see some drops of water. This is due to condensation.

Note : You should do this experiment under the guidance of your teacher.

Fun Science

Study the given pictures and write the name
of substances at different states in the space below.

Substances States
………………………........…………… ………………………........……………

………………………........…………… ………………………........……………

………………………........…………… ………………………........……………

100 MY WAY Science, Health and Physical Education - 5

10Chapter

ENERGY

What ? Why?

You’ll learn to We use different forms of energy every
 differentiate between renewable and day. We need heat energy in cooking, and
keeping us warm. Light energy helps to see
non-renewable sources of energy with things around us. We need energy to do our
works. You can keep yourself warm by heat
examples. energy.
 list the effects and uses of different

forms of energy such as heat, light,

sound, electricity, magnetic energy, etc.

Fire (energy) in history
The production and control of fire was
a turning point in the cultural aspect
of human evolution. It allows human
to cook food and obtain warmth
and protection from predators and
insect. Evidence of the controlled
use of fire by Homo erectus have
been found by scientists.
In our country, people used to light fire using special stone known as
“Darshan Dhunga”. We also worship fire as Agnidev in our culture.

Name any three things that can be used to make fire.
_____________________________________________________
How do your parents get fire at your kitchen ?
_____________________________________________________
Write a name given to fire in your culture.
_____________________________________________________

MY WAY Science, Health and Physical Education - 5 101

We need energy
Energy is defined as the capacity of doing work. We require
energy to perform all our activities. For example, we need heat
energy to cook food, light energy to see things, electrical energy
to run electric appliances such as TV, radio, etc.

Renewable energy sources
The sources from which we get energy are called the source
of energy. For example, the sun, coal, wood, water, etc. Some
of the energy sources can be used again and again. These are
called renewable energy sources. Sun energy, river water, wind
are the renewable energy sources.

solar energy wind Energy hydro electric energy

Non-renewable energy sources
Some sources of energy can be used only once. For example,
after we burn wood, we cannot use ashes again to get energy.
These types of sources are called non-renewable energy sources.
Coal, petrol, fuel are other examples of non-renewable energy
sources.

coal firewood petrol

102 MY WAY Science, Health and Physical Education - 5

Quick Test 1: From your home
Write an example of non-renewable energy source at your home.
___________________________________________________
Write an example of renewable energy source at your home.
___________________________________________________

Form of energy
We use different forms of energy to do our work. Some forms
of energy are heat energy, light energy, sound energy, electrical
energy and magnetic energy. They are explained as follows:

Heat energy
The sun is the main source of heat energy. We can also get heat
energy from burning wood, fuel, electricity, etc. Heat energy
changes the volume of substance and the state of matter. For
example, when we heat ice, it changes into water. By heating
water, we can raise its temperature.
We use heat energy to keep our body warm, to cook our food, to
run vehicles, to dry our clothes etc.

Keeping our body warm Drying clothes

sources of heat energy uses of heat energy

MY WAY Science, Health and Physical Education - 5 103

sun candle bulb torchlight

Light energy

Light energy helps us to see things. The sun is the main source
of light energy. Besides the sun, we can get light energy from
burning wood, candles, electric bulbs,
etc. Burning objects like wood and THINK Critically

candles give both heat and light energy. Find out the odd
energy source in the
Sound energy following group -
Sound energy is produced by movement i. Sun ii. Heater

iii. Candle iv. Bulb

or vibration of an object. These vibrations travel through air and
reach our ear. We can hear only the sound. Musical instruments
like guitars, tabalas, madals, etc. can produce sound energy.
When we hit the bell, we can hear sound. Hearing sound helps
us to communicate.

Quick Test 2: From your home
a. Name a bird that produces pleasing sound. ___________
b. Name an insect that produces its own light. ___________
b. Name a bird that keeps itself warm by its fur. _________

104 MY WAY Science, Health and Physical Education - 5

Electrical energy
Electrical energy can be obtained from batteries, cells, hydropower,
etc. Electrical energy can be converted into heat and light energy.
For example, electric heater, tube light, etc. Nowadays, electrical
energy is used everywhere. People use electrical energy to run
machines in factories, vehicles, TV, radio, computer etc. Electrical
energy is produced by running water (hydropower) and also from
moving wind (wind mill).

Electrical instruments Source of electrical energy

Magnetic energy Did YOU know ?
Energy present in a magnet is called
magnetic energy. The magnet attracts Lodestone is natural magnet.

pins, nails towards itself due to magnetic energy. In industries
magnetic energy is used to carry heavy iron, and other magnetic
substances. Magnetic substance is also used in phone, TV,
radio, etc. Magnets are also used to find direction in compass.
Freely suspended magnets always turn towards north and south
direction which helps us to identify direction easily.

MY WAY Science, Health and Physical Education - 5 105

Quick Test 3: From your home
Name any two uses of electricity at your home.
a. ______________________ b. _____________________
Name a device that contains magnet.
___________________________________________________

The sun is the ultimate source of energy
The sun is the main source of energy for all living things. It
provides heat and light energy. Plants use this light energy to
prepare their food during photosynthesis. We as well as all
animals depend on plants directly or indirectly for food.
Sun energy is used as solar energy to do different activities.
Solar energy can be used to light bulbs, cook food, run cars, etc.
As solar energy is pollution-free and renewable, we should use
it more.

Conserving energy
Without energy it is difficult to work. So we must conserve our
energy sources. We should use less petrol, wood and fuel. They
are non-renewable energy sources. We should turn off our
electrical appliances when they are not in use. We should plant
more trees because they provide us wood.

Quick Test 4: From your home
Write a way to conserve energy at your surrounding.
___________________________________________________
Write a way to reduce the use of petrol in your surrounding.
___________________________________________________

106 MY WAY Science, Health and Physical Education - 5

Quick Test 5: All in one

True or False ? If false, correct it.
1. The sun, water and air are the examples of non-renewable

energy sources.
2. We can get sound energy from burning wood.
3. Heat energy helps us to see things.
4. The sun is the main source of light energy.
5. Hearing sound helps us to communicate.
6. The energy present in a magnet is called electrical energy.

Work Further

Do the following activities : K

1. Fill in the blanks with the words given below.
candle/sun/energy/electrical energy/vibration/

temperature/fuel/source
a. We require .................. to perform all our activities.
b. The sun, coal, wood and water are  .........................

of energy.
c. ........................... is an example of non-renewable

energy source.
d. The ..................... is the main source of heat energy.
e. By heating water, we can raise .................................

of substance.
f. .............................. gives both heat and light energy.
g. Sound energy is produced by ..................................

of objects.
h. ............................. is produced by hydropower and

also from moving wind mills.

MY WAY Science, Health and Physical Education - 5 107

2. Answer the following questions.

a. What are the uses of heat energy ? K
b. What are the sources of light energy ? C
C
c. When and how can we hear sound ? K
d. What are the uses of magnets ? C

3. Answer the following questions in detail.

a. Describe the use and sources of electrical energy.
b. How can we conserve energy ?
c. What are renewable and non-renewable energy
sources ?

4. Write short notes on

a. Change of state b. Types of energy
c. Evaporation d. Conserving energy

My way of doing science Ap

Take a magnet and point it to the collection of metals. Find
which metal is magnetic and which are non-magnetic.

Note: Magnetic substances are attracted towards the magnet. Non-magnetic
substances are not attracted towards the magnet.

Fun Science

Classify the following as renewable or
non-renewable energy sources: Candle, matchstick, petrol,
torchlight, hydropower, solar, headlight of a car, bicycle dynamo.

Renewable source Non-renewable source

108 MY WAY Science, Health and Physical Education - 5

8UNIT

WEATHER AND CLIMATE

Unit Highlights

You are going to learn about
Weather and Climate
• Weather and climate are different
• Solar radiation
• Monsoon
• Water cycle
• Humidity
• Weather forecasting
Clouds
• Clouds in the sky
• Cirrus
• Cumulus
• Stratus
• Nimbus

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MY WAY Science, Health and Physical Education - 5

11Chapter

WEATHER AND CLIMATE

What ? Why?

You’ll learn to Climate affects the lifestyle of living
 differentiate between weather and things at a place.Weather affects our daily
activities. You can choose to carry things
climate. you need to be safe from hot, cold and rain.
 mention the factors that affect the

weather and climate.
 describe the change occurring on the

surface of the earth.

Satellite monitoring weather each day
Developed countries like USA, Russia
an UK have launched the weather
satellites. The satellites go round the
earth and gather information about
humidity, cloud, temperature, wind
and other atmospheric condition. The
information is then sent to ground
stations where many people work
together to forecast the weather at different parts of the world.
Knowledge of weather is very much important for pilots.

How do you get information about weather each day ?
_____________________________________________________
Can you predict weather by observing the sky ?
_____________________________________________________
Who needs to be regularly updated with the weather conditions ?
_____________________________________________________

110 MY WAY Science, Health and Physical Education - 5

Weather and climate are different
Weather defines the condition of a place at a given time. Weather
may change within an hour, a day or a week. Even in a day the
morning can be cloudy, while in the daytime it can be sunny or
rainy. So weather changes continuously.
Climate describes the weather of a particular place for a longer
period of time. So average weather of a place at a given time is
called climate. Height of a place from the sea level, amount of
rainfall, solar radiation, water cycle and humidity are some of
the factors that affect climate.

Quick Test 1: From your surrounding
Write the features of weather today.
___________________________________________________

Solar radiation
Earth revolves around the sun, tilting at an angle of 66.5o. During
this revolution, when northern hemisphere gets direct sunlight,
the climate is hotter there at the same time than in southern
hemisphere which experiences relatively cold weather.
Because of the revolution of the earth around the sun, we
experience different seasons in a year. So, the amount of sunlight
reaching the earth surface determines the change in climate.

Quick Test 2: From your surrounding
Write the name of the season today.
___________________________________________________

MY WAY Science, Health and Physical Education - 5 111

Monsoon
Monsoon is characterized by
frequent and heavy rainfall. In our
country we usually have monsoon
during Jestha and Ashad months.
Clouds formed at the bay of Bangal
cause monsoon in Nepal. When
these clouds moved along the wind
reaches Nepal, it causes heavy rainfall. Farmers of our country
are heavily dependent on the monsoon for planting rice. Nepal is
a agricultural country. So the delay of monsoon or fewer monsoon
affects our economy. Heavy monsoon sometimes causes flood.
This causes damage to our crops, animals and property. It can
even cause loss of human life.

Quick Test 3: From your surrounding
Name the months the monsoon starts and ends.
a. ______________________ b. _____________________

Water cycle THINK Critically

Water cycle causes rainfall. Due to What is the source of
the heat of sunlight, water from lakes, winter rain in Nepal ?

ponds, rivers and seas evaporates and goes up. This water
vapour forms clouds. This water vapour condenses forming
water droplets. When these droplets become heavier they fall
as rain, hailstones and snow. In this way, water cycle causes
rainfall. Climate is usually cool at the place receiving more
rainfall. Weather is colder at the places having snowfall.

112 MY WAY Science, Health and Physical Education - 5

Humidity
Humidity is the amount of water vapour
in the air. High water- content in the air
is necessary to form cloud and rain. So
humidity determines the likelihood of
rain, fog and dew. We feel hotter during the days having higher
humidity. If humidity is high, sweat does not come from our body.

Weather forecasting
Have you heard of weather
forecasting on radio or television?
They usually give information
about the wather we are going to
have the next day or next week.
Meteorologists are scientists who monitor weather condition.
They use information of humidity, solar radiation, amount of
rainfall and many other factors to forecast the weather. This
information can be used for forecasting weather up to five days.

Quick Test 4: From your surrounding
a. Name the most humid month in Nepal ________________
b. Name the least humid month in Nepal _______________

We cannot control weather but it highly Did YOU know ?
influences our life, what we wear, what we
eat and what we do. So basic knowledge There occurs strong wind in
of weather forecasting helps to plan our Jomsom at noon each day.

day. If we have a sunny day, we can expect the similar weather the
following day. If we see lots of dark clouds covering the morning sky,

MY WAY Science, Health and Physical Education - 5 113

we can expect to have rainfall during the daytime. We can expect
short duration of shower if it happens while sunshine. If we see
clouds covering on winter nights we can expect to have warm night,
as clouds prevent escape of heat radiation from the earth surface.

Weather monitor Different types of Theromameter

Quick Test 5: From your experience

The excess cloud at evening makes night
___________________________________________________
The excess of dark cloud at morning makes the
___________________________________________________

Quick Test 6: All in one

Fill in the blanks with the correct words given below.
flood / water cycle /short /monsoon/water vapour/ rainfall
1. In our country we usually have …………………….. during

Jestha and Asadh months.
2. Weather changes continuously with ............. span of time.
3. Clouds formed at the Bay of Bangal cause .......... in Nepal.
4. Heavy monsoon sometimes causes ………………………....... .
5. Water cycle causes ............................................................ .
6. Humidity is the amount of .................................. in the air.

114 MY WAY Science, Health and Physical Education - 5

Work Further

Do the following activities : A
K
Answer the following questions.
1. How does monsoon affect our economy ? C
2. What are the factors that affect climate ?
3. What determines the likelihood of rain, fog and dew ?
4. Why do we experience different seasons in a year ?
5. Describe water cycle.
6. What is the importance of the basic knowledge of

weather forecasting ?

My way of doing science Ap

Listen to the radio or TV and make reports on
weather throughout a week. Present your data in
the table given below.

Days Temperatures Rainfall Weather condition
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday

Fun Science

Find out diagram and news related to the
importance of monsoon in Nepal. Paste them in your classroom wall.

MY WAY Science, Health and Physical Education - 5 115

12Chapter

CLOUDS

What ? Why?

You’ll learn to Clouds are formed in different heights from
 explain clouds. the earth surface. Rainfall, hailstorm and
 identify the different types of clouds. thunderstorm are caused by them. You
can decide whether to carry raincoat or
umbrella by observing the clouds.

Hurricane and cyclone
Hurricanes are violent storms. They are
also known as typhoons or cyclones
depending on where they occur.
Only the tropical cyclones that form
over the Atlantic Ocean or Eastern
Pacific Ocean are called hurricanes.
Tropical Cyclones are like giant engine
that use warm and moist air as fuel. Hence, they are always formed
over warm ocean water.

Have you heard the news about cyclones ?
_____________________________________________________
Have you watched them in TV ?
_____________________________________________________
Write the year you have faced strong wind.
_____________________________________________________
Write the month you have faced strong rainfall.
_____________________________________________________

116 MY WAY Science, Health and Physical Education - 5

Cloud in the sky
Most of the time sky is covered with
cloud. When there is less cloud, the
earth surface gets more sunlight and
days become brighter. But when the sky
is covered with dark and thick clouds,
days become gloomy because clouds
block sunlight and we receive less sunlight. Clouds are generally
white, grey or dark brown in colour. They differ from each other
in shape and size too.
Clouds are made up of water droplets which are formed during
water cycle. Due to the heat from sunlight, water from seas,
rivers, ponds, etc. evaporates and goes up. When water vapor
cools down, it changes into water droplets. These water droplets
join together and form clouds. Depending upon the colour and
nature of clouds, they are classified into four different types.
1. Cirrus 2. Cumulus 3. Stratus 4. Nimbus

Quick Test 1: From our understanding

Name a factor that forms cloud.
___________________________________________________

Cirrus 117
Cirrus clouds are considered high
clouds as they are formed above
6000m. So they remain at the top in
the sky. It generally appears white or
light grey in colour. It is thin and curly

MY WAY Science, Health and Physical Education - 5

in appearance. It looks as if somebody has torn up cotton into
smaller thin pieces and scattered in the sky. As it lies very high, it
does not contain water droplets, instead, it contains ice crystals.
We expect heavy rainfall with hail if the sky is mostly covered
with cirrus.

Cumulus

Cumulus clouds are low level clouds
as they are formed generally less than
2000m. above from the ground. They
are white thick clouds which look like
cauliflowers. In presence of sunlight
the upper part looks bright and white while lower part looks dark
and grey. Weather becomes gloomy if the sky is mostly covered
by cumulus cloud as it blocks sunlight from reaching the earth
surface.
Did YOU know ?
When cumulus clouds are white and puffy,
it usually indicates nice weather but if Clouds develop
they grow into big grey clouds, we expect both vertically and

horizontally.

to have rainfall.

Quick Test 2: From your understanding

1. Cirrus is …………........................................…………. in colour.
2. Cumulus is ………………....................................…… in colour.

Stratus THINK Critically
Stratus are also low level clouds being
closer to the earth surface. The colour Why do clouds in the sky
form different shape ?

118 MY WAY Science, Health and Physical Education - 5

of these clouds varies from dark grey to
the nearly ash colour. They often cover
the entire sky. When they are close to
the ground they look like fogs. Weather
is usually calm; but sometimes when
they become thicker and grayish, it
may rain.

Nimbus
Nimbus clouds are also formed
generally below 2000m. They also are
thick and very dark in colour. The shape
of Nimbus clouds is not fixed. Nimbus
clouds are darker than other clouds
and contain more water. When the sky is covered with Nimbus,
it is expected to have heavy rainfall.

Quick Test 3: From our understanding
Name a type of cloud you have seen today.
___________________________________________________

Quick Test 4: All in one

Write a feature for each of the following types of cloud.

1. Cirrus __________________________________

2. Cumulus __________________________________

1. Stratus __________________________________

1. Nimbus __________________________________

MY WAY Science, Health and Physical Education - 5 119

Work Further

Do the following activities :

Answer the following questions.

1. When do days become gloomy ? Why ? C
2. Why do cirrus clouds not contain water droplets ? K

3. When do we have heavy rainfall with hail ? Ap
4. What are the characteristics of nimbus ?
5. Write the types of cloud.

6. Identify the types of the cloud.

Pictures name of clouds
......................................................

......................................................

......................................................

My way of doing science Ap

Go outside the classroom to observe the cloud in the sky
and write a report on it.

Fun Science

Colour the following diagram.

120 MY WAY Science, Health and Physical Education - 5

9UNIT

ASTRONOMY AND GEOLOGY

Unit Highlights

You are going to learn about
Planets, Stars and Solar System
• Stars and planets
• The member of solar system
• Asteroid
• The moon: natural satellite
• Phases of moon
• Constellation
Shadow and Eclipse
• Shadow
• The eclipse
• Lunar eclipse
• Solar eclipse
The Earth
• The earth supports life
• Layers of the earth
• Causes of change in earth surface

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MY WAY Science, Health and Physical Education - 5

13Chapter

PLANETS, STAR AND SOLAR SYSTEM

What ? Why?

You’ll learn to The sun, the moon and stars are space
 introduce our solar system. objects. The sun is the source of light and
 differentiate between the sun and the heat. Rotation of the earth around the sun is
the main cause of seasonal change. You can
stars. develop your career in astronomy in future.
 explain the different phases of the

moon.

International Space Station (ISS)
ISS is an artificial satellite
of the earth. It is habitable.
Hence, scientists live and do
many scientific experiments
there. The ISS is about 400
km above the earth surface.
The station moves round the
earth and it covers 7.6 km
in one second. Sometimes, the space station can also be seen by
naked eye from the earth as small and moving tiny dot.

Have you watched any TV program about ISS ?
_____________________________________________________
Have you watched any movie related to space ?
_____________________________________________________
Do you like to be astronomer in future ?
_____________________________________________________

122 MY WAY Science, Health and Physical Education - 5

Stars and planets
The space above us is very huge. This
huge empty space is also known as
universe. There are many objects in it.
Our earth, sun, moon are some objects
which are also known as space objects
or celestial objects. Stars are the objects with their own light.
They have very high surface temperature. There are billions of
stars in the space. Only few of them appear as shining dots to us.
Our sun is the nearest star to us. It is big ball of fire. Everything
is in the molten state or gaseous state in the star.
Planets are the objects in the space
without their own light. They have low
surface temperature. There are eight
planets which revolve round the sun.
They are Mercury, Venus, Earth, Mars,
Jupiter, Saturn, Uranus and Neptune.
The outer planets Jupiter, Saturn, Uranus and Neptune are also
known as Jovian planets because they are huge in size and
have gaseous surface. These eight planets and the sun form
the solar system. All the planets move round the sun. The path
of the planet around the sun is known as orbit. The motion of
the planets around the sun is known as revolution.

Quick Test 1: From your understanding

1. The path of planet around the sun is called ……………………..
2. The motion of planet around the sun is called …………………
3. There are ……………….......……. planets in the solar system.

MY WAY Science, Health and Physical Education - 5 123

The members of solar system
The sun
The sun is a star, a hot ball of fire at the centre of the solar
system. Its surface temperature is very high. Without its heat
and light, life on the earth would be impossible.

Mercury
Mercury is the nearest planet to the sun. It
takes around 88 earth days to complete one
revolution around the sun along its orbit. At
day time, it is superheated by the sun but it is
pretty cold at the night time. There is no atmosphere in this planet
and hence no life as well. It is the sphere of 4878 km in diameter.

Venus
Venus is only a little smaller than our earth.
It has thick layer of toxic gas which cannot
support life. It is second closest planet to the
sun. It goes round the sun and takes 225 earth
days to make one complete rotation. It appears brighter than any
other space object in the sky. Its diameter is about 12104 km.

Earth
The earth is our planet. We live here. It
has thick layer of atmosphere and water to
support life. It is third closest planet to the
sun. The earth takes 365 days to complete
one revolution around the sun. It is also called one earth year.
The diameter of the earth is around 12760 km.

124 MY WAY Science, Health and Physical Education - 5

Quick Test 2: From your understanding

Write a reason why Mercury cannot have life.
___________________________________________________
Write a reason why Venus cannot have life.
___________________________________________________

Mars
The Mars is the cold planet and appears red
due to presence of the dust of iron oxide. It
has thin layer of atmosphere. There is no
evidence of life there. It has two moons. It
takes around 687 earth days to complete one revolution around
the sun. Its diameter is about 6787km.

Jupiter
It is the massive and huge planet in our
solar system. It has few dozens of moons.
It makes a complete orbit around the sun in
about 12 earth years which is approximately
4333 earth days. This planet has strong magnetic field. It has
the average diameter of 428400km.

Saturn
The Saturn is the unique planet which bears
many beautiful ringlets and numerous
moons. It takes around 29 earth years to
complete one revolution around the sun. It does not have solid
surface. Its diameter is 120500 km.

MY WAY Science, Health and Physical Education - 5 125

Quick Test 3: From your understanding
1. Diameter of Jupiter is ……………………………….......................
2. Diameter of Saturn is ……………………………….......................

Uranus
It is the seventh planet from the sun. It is
very cold there and most part of it is covered
with icy material. It has diameter of 51120
km. This planet also has numerous moons
along with faint ringlets.
It takes around 84 earth years to complete its orbit around the sun.
Neptune
Neptune is the eighth planet in our solar
system. It is mostly covered with icy materials.
It takes around 164 earth years to make one
revolution around the sun. It is 17 times as
massive as the earth. The diameter of this planet is 49530 km.
These days Pluto is not considered as planet due to its peculiar
property. It is dwarf planet.

Quick Test 4: From your understanding
1. Diameter of Uranus is …………...............…………………….......
2. Diameter of Neptune is ……………………...............……………..

Asteroid
Asteroids are also small planets in our solar system. They are

126 MY WAY Science, Health and Physical Education - 5

rocky and airless with irregular shape.
The region between the Mars and the
Jupiter is also known as asteroid belt.
There are large number of asteroids
in the asteroid belt. The asteroids also
revolve round the sun.

The moon: Natural satellite
Satellite is anything that goes round the planet. The moon is the
natural satellite of the earth. It takes approximately 29.5 days
to complete one revolution around the earth. When the moon is
big and round in the sky at night, we call it full moon day.

Phases of moon Did YOU know ?

No space objects are in rest. They are all The sun also resolves
moving. The earth goes round the sun and round galactic centre.
the moon goes round the earth. Due to
the rotation, moon appears in different shapes from the earth.
The phases of the moon are the different ways the moon looks
from the earth during a month. We only see that much part of
the moon which is lit up by direct sunlight.

After the crescent moon, the size gets bigger and bigger every
night until full moon. This phase of waxing of the moon is known
as bright half (shukla pakchha).

MY WAY Science, Health and Physical Education - 5 127

After the full moon, the size decreases day by day until new
moon. This phase of wanning of the moon is known as dark half
(krishna pakchha). The new moon is when the moon is all dark.
The C-shaped moon seen after the new moon day is known as
crescent moon.
The first quarter of the moon is when its half part is visible during
its waxing period. The whole process of waxing and wanning of
moon is due to rotation of the moon around the earth.

THINK Critically

Find the odd one in
the following group.
i. Sun ii. Galaxy
iii. Constillation

Quick Test 5: From your experience
1. The bright half lasts for ………………...................……….. days.
2. The dark half lasts for ……………...................……………. days.

Constellation
The patterns formed by a group of few stars are known as
constellations. People have identified constellation since ancient
time. Some constellations are also used as zodiacs in astrology.
There are 48 ancient constellations. Only 12 of them are zodiacs.
Some of them are Leo, Libra, Scorpio and Sagittarius etc.

128 MY WAY Science, Health and Physical Education - 5

International Astronomical union has defined 88 constellations
officially.

Quick Test 6: From your culture

1. Write the name of your zodiac ……….........………………………
2. Write the number of zodiacs ………………............………………

Quick Test 7: All in one

True or False ? If false, correct it.

1. Our sun is the farthest star to us.
2. All the planets move around the sun.
3. The earth lies at the centre of the solar system.
4. Venus takes 365 earth days to make one complete rotation.
5. Jupiter has strong magnetic field.

Work Further

Do the following activities : K

1. Fill in the blanks with the words given below.
orbit/earth days/planet/light/celestial object
a. Like our earth, there are some objects known as ...

...............................................
b. Stars are the objects with their own .........................

MY WAY Science, Health and Physical Education - 5 129

c. The path of the planet around the sun is known as K
.................................
C
d. Mercury takes around 88 ............... to complete K
one revolution. A
A
e. Satellite is anything that goes round the ..................

2. Answer the following questions.
a. What are Jovian planets ? Why are they called so ?
b. In what state do the things in the star exist ?
c. What is revolution ?
d. What made life on the earth possible ?
e. What are asteroids ?

f. Write difference between planets and stars.

3. Write short note on
a. Planet b. Constellation c. Satellite d. Asteroid belt

My way of doing science Ap

Draw a diagram of the moon at full moon night. Now
see the moon in the next 7 days in the sky and draw the
diagram of each day in the space given below.

1 day 2 day 3 day 4 day 5 day 6 day 7 day

Now decide whether it is waxing or waning of the moon.

Fun Science

Find news related to astronomy in newspaper
and paste it on wall of your classroom.

130 MY WAY Science, Health and Physical Education - 5

14Chapter

SHADOW AND ECLIPSE

What ? Why?

You’ll learn to Eclipse is astronomical event that people
 list the causes of eclipse or eclipses. have experienced for many years now. You
 categorize different types of eclipses. can explain the reason behind eclipse.

Eclipse and ancient belief in China
In ancient China, the solar and lunar
eclipses were regarded as heavenly
sign that foretell the future of
Emperor. Hence, predicting eclipse
were of high importance of the state.
Over four millennium years ago, two
Chinese astrologers were murdered
as they failed to predict solar eclipse.
The ancient Chinese believed that the solar eclipse occurs when a
celestial dragon devours the sun. The dragon attacks the moon in
Lunar eclipse according to them. But these days, Scientists have
revealed the fact behind the eclipse.

Have you observed solar/ lunar eclipse ?
_____________________________________________________
Is there any myth associated to eclipse in your locality ?
_____________________________________________________
Name an astrologer in your locality.
_____________________________________________________

MY WAY Science, Health and Physical Education - 5 131

Shadow
Shadow of an object is formed
when the object blocks the beam
of light. The shadow always
appears on the other side of the
object opposite to the light source.
Do all objects form shadow?

Glass slab does not form shadow. Book forms its shadow.

Transparent objects do not form shadow since light can easily
pass through them. Glass and plastic are transparent. Opaque
objects form shadow because light cannot penetrate them.
Books, brick stone etc are opaque objects.

You can also make shadow of a ball using torch light. Place a ball
on table. Close door and window to make dark in the room. Light
the ball with torch light to make its shadow on the wall.

You will observe black disc on the wall. You can move the ball or
light source to change the position of the shadow.

The region of complete dark in shadow Did YOU know ?
is called umbra region. This is formed by
total blockage of light beam. The fainter An ancient time, people
shadow around the umbra is known as used eclipse as an event
penumbra region.
to intemediate other.

132 MY WAY Science, Health and Physical Education - 5

Quick Test 1: At your home

Name any two transparent objects at your home.
a. ______________________ b. _____________________
Name any two opaque objects at your home.
___________________________________________________

The eclipse
No space objects are at rest. The earth moves round the sun on
its orbit. Similarly, the moon moves round the earth. Both the
earth and the moon are lighted up by the sun. Hence, shadows
are formed on the other side opposite to the sun. The eclipse is
the celestial event when a space object or its shadow covers up
another space object fully or partially. From the earth we observe
lunar eclipse and solar eclipse.

Lunar eclipse
Earth revolves around sun. Similarly,
moon also revolves around earth.
During these revolations when
earth comes between sun and
moon, lunar eclipse occurs.
In this case, the shadow of the earth is seen on the moon surface
(hence moon cannot be seen) which we call the lunar eclipse.
This phenomenon occurs only in the full moon night.
When the moon moves through the umbra region during its
revolution, a total lunar eclipse is seen from the earth. A partial
lunar eclipse is appears while the moon is on its way in the
penumbra region.

MY WAY Science, Health and Physical Education - 5 133

We can observe the lunar eclipse even with our naked eye. There
is no harm in it. But we cannot see lunar eclipse in every full
moon night since the earth sun and moon do not lie exactly in
straight line in every full moon night.

Quick Test 2: From your experience

The time and date of lunar eclipse you have recently observed is
___________________________________________________

Solar eclipse

During the revolution of the earth
and the moon, a situation is reached
at which the sun, moon and the
earth are along a straight line with
the moon between the earth and the
sun. In this case, the moon blocks
the sunlight and its shadow is casted on the earth surface. This
phenomenon is known as solar eclipse. The people in the umbra
region will have full solar eclipse whereas there will be partial
solar eclipse for the people in the penumbra region. The solar
eclipse occurs on new moon day. We
should not see the solar eclipse with THINK Critically
our naked eye. You can use special
goggle to see the event. Can you say why there is
no solar eclipse on each
new moon day ?

Quick Test 3: From your experience

Name a thing that can be used to observe solar eclipse.
___________________________________________________

134 MY WAY Science, Health and Physical Education - 5

Quick Test 4: All in one

True or False ? If false, correct it.

1. Transparent objects form shadow.
2. The Sun moves round the earth on its orbit.
3. It is harmful to observe the lunar eclipse with naked eye.
4. During lunar eclipse, the moon lies between the earth

and the sun.
5. The solar eclipse occurs in full moon day.

Work Further

Do the following activities : K
A
1. Fill in the blanks with the correct words given below.
earth/umbra region/goggle/shadow/penumbra

region

a. The .................................. always appears on the
other side of the object opposite to the light source.

b. The region of complete dark in shadow is known
as ...........................................

c. The fainter shadow around the umbra is known as.
.......................................................

d. From the .............................. we observe both lunar
eclipse and solar eclipse.

e. We should use special ..............,,.......... to see the
solar eclipse.

2. Answer the following questions.
a. Why do transparent objects not form shadow?
b. Why can we not see lunar eclipse in every full moon night ?
c. Differentiate between solar eclipse and lunar eclipse.

MY WAY Science, Health and Physical Education - 5 135

d. How does solar eclipse occur ? C

My way of doing science Ap

Write a report including the diagram recently
occurred lunar/solar eclipse. (You can use internet/
newspaper)Include the following in your report.
(1) Date (2) Types of eclipse (3) Start time (4) End time

Fun Science

M2
M4 M5
M3
M1

Identify the above picture and answer the following questions.
1. Do you observe eclipse when you are at M1 position ?
__________________________________________________
2. What type of eclipse is formed when you are at M2 position ?
__________________________________________________
3. What type of eclipse is formed when you are at M3 position ?
__________________________________________________
4. What type of eclipse is formed when you are at M4 position ?
__________________________________________________
5. Do you observe if you are at M5 position ?
__________________________________________________

136 MY WAY Science, Health and Physical Education - 5

15Chapter

THE EARTH

What ? Why?

You’ll learn to The change in the earth surface is
 describe the internal structure of the continuous process. Different layers of the
earth have different features and change in
earth. different ways. You can develop your career
 describe the causes of changes on the as geologist in the future.

surface of the earth.

Mine in the earth crust
Our earth is store house of different types of
raw materials which are useful to mankind.
People have dug many mines to get the raw
materials. The world’s deepest mine is in
South Africa. It is Tau-Tonga gold mine which
is 4 km in depth. Scientists use A.C . to cool
the environment inside the deep mine.

Is there any mine near your locality ?
_____________________________________________________
Name deepest part of land in your locality.
_____________________________________________________
Name the highest part of the land in your locality.
_____________________________________________________
Write the minimum and maximum temperature in your locality
throughout a year.
Minimum ______________ Maximum ______________

MY WAY Science, Health and Physical Education - 5 137

The earth supports life
The earth is the planet where
we live in. The earth has surplus
of water, favorable temperature
and oxygen in its atmosphere to
support the life of living things.
It moves round the sun and
makes one complete round in
365 days (one year) which we call the revolution. This motion
causes the change in seasons and makes favorable condition
to grow different crops through out the year.
Well, the earth also spins round its
north- south axis which we call the
rotation. It takes 24 hours (one day)
to complete one complete rotation
around its north south axis. Due to
this motion, only half part of the
earth is exposed to sun light for 12 hours which we call day.
There will be night for 12 hours in the other half of the earth.
The earth is approximately a sphere with average diameter of
12735 km. As we move to the centre from the surface, we find
different structures and layers of different properties just like a
boiled egg.

Quick Test 1: From your understanding
Write two main reasons on why earth supports life.
a. ______________________ b. _____________________

138 MY WAY Science, Health and Physical Education - 5

Layers of the earth
The earth has also different layers. They are Crust, Mantle and
Core.

Crust

The crust is the outer most layer of the earth. It is mainly
made of different types of rocks. Mountain, hills, plain,
plateau and valley are different landscapes on the crust. The
thickness of this layer varies from 5 km to 50 km. The crust
below the ocean is known as oceanic crust which is about 5
km in thickness. The continental crust is about 50 km thick
in maximum. The crust is less than one percent of the total
weight of the earth. There is increase in temperature as we
go deep down the crust.
World’s deepest mine is Tau Tonga gold mine which is about
4 km in depth. The temperature inside the mine is 55 degree
Celsius. Workers cannot work at
this temperature hence A.C.is used THINK Critically
to cool the environment inside the
deep mine. Why do volcanoes eject
out hot material ?

MY WAY Science, Health and Physical Education - 5 139

Quick Test 2: From your understanding
1. The thickness of Crust is …………………………........................
2. The deepest mine in the world is ……………………........………

Mantle
The layer just below the crust is known as mantle. The thickness
of this layer is approximately 3000 km. The temperature of this
layer is different depending on the depth. Near the boundary
between the crust and mantle, the temperature is about 800
degree Celsius. But it is around 4000 degree in the innermost
part of the mantle. Major component of the mantle is silica,
magnesium and iron. They are in molten state due to high
temperature. The molten substance in the mantle is also known
as magma which evolves out during volcanic eruption.
Core
The core is the innermost part of the earth. There is high
pressure and high temperature. The core is further divided into
two layers. They are outer core and inner core. The outer core is
about 2100 km in thickness. The substances found here are iron,
nickel, magnesium and cobalt in molten form. Its temperature
is around 4000 degree Celsius. The inner core is about 1300
km in thickness which contains heated material of temperature
of around 5400 degree Celsius. But due to high pressure, the
materials are confined to solid form.

Quick Test 3: From your understanding
1. The thickness of mantle is ……………………………..............…..
2. The temperature of inner core is ……………………………………

140 MY WAY Science, Health and Physical Education - 5

Causes of change in earth surface

The earth surface is under continuous change. There are many
causes behind this. Some are man-made
whereas others are natural causes. Did YOU know ?

The approximate mass of
the earth is 6.0 x 1024 kg.
Man-made causes

We human beings carry out different activities. Some of them
deteriorate the quality of the earth surface. They are deforestation,
construction and waste etc. People cut down trees haphazardly
for agriculture, habitat and grazing. This activity degrades the
quality of soil and hence it cannot hold water which later induces
landslide and soil erosion. Hence we must plant trees in our
bare land to make the earth surface a better place to live in.

Natural causes
The natural causes responsible to
change the earth surface are rainfall,
volcano, earthquake, drought and
storm etc. Drought of sufficiently long
interval of time can dry up the soil. It
expands the rock at day time and the
rock gets cooled and contracted at night. Continuous expansion
and contraction breaks up the rock and can cause soil erosion.
The volcano ejects out large amount of hot magma to the earth
surface which can burn all the vegetation. When they cool, they
solidify into rock. Similarly, strong rain can induce landslide
and soil erosion. The earthquake is another major cause to
change the earth crust. Due to severe earthquake, there can be
fragmentation and rupturing of the rock on the surface.

MY WAY Science, Health and Physical Education - 5 141

Quick Test 4: From your surrounding

Two main reasons of changing earth surface at your locality are:
a. ______________________ b. _____________________

Quick Test 5: All in one

True or False ? If false, correct it.
1. The earth takes 12 hours to complete one rotation around

its north south axis.
2. The earth has four different layers.
3. The crust is mainly made of different types of rocks.
4. The thickness of mantle layer is approximately 300 km.

Work Further

Do the following activities : K
C
1. Fill in the blanks.
mantle/core/outer most layer/sphere
a. The shape of earth is approximately a …………...….
b. The crust is the .................................. of the earth.
c. The temperature of …………….…………… is different

depending on the depth.
d. There is high pressure and high temperature in …....
2. Answer the following questions.
a. What causes the change in seasons ?
b. Why do we have day and night ?
c. Describe the natural causes and man-made causes

that change the earth surfaces.

142 MY WAY Science, Health and Physical Education - 5

d. What is revolution ? K
e. What is magma ? A
f. Differentiate between rotation and revolution of the C

earth.

3. Write short note on
a. Mantle b. Natural disaster c. Core

My way of doing science Ap

Make a trip to near by river along with your science teacher.
Writer a report in how human activaties have caused
degradation in the quality of land there.

Fun Science

Identify the above picture and answer the following questions.
Compare the structure of earth with that of mango.
Which part of mango is like earth ?
…………………………………………………………………...............................
Which part of mango is like mantle ?
…………………………………………………………….....................................
Which part of mango is like core ?
……………………………..........................................................……………

MY WAY Science, Health and Physical Education - 5 143

UNIT 10

INFORMATION AND TECHNOLOGY

Unit Highlights

You are going to learn
about
Information and
Communication
• Information
• Computer
• Internet and Email
Local technology
• Our technology
• Dhiki
• Janto
• Improvised cooking store

Manually operated mill (col)

Visit : www.symphonypub.com for further learning
144 MY WAY Science, Health and Physical Education - 5

16Chapter

INFORMATION AND COMMUNICATION

What ? Why?

You’ll learn to We have mobile, emails, internet, radios
 introduce science and technology. and TV which are faster means to share
 identify the different sources of information. With the help of imformation,
you can plan your visit at holidays.
information.
 explain the importance of computer as

source of information.

The inventor of Telephone
The development of
Telephone and mobile
are very much important
part of our life these days.
There is contribution of
many people in making
telephone. However, the
credit of inventing the first
practical Telephone goes
to Alexander Graham Bell. He was an engineer born in Scotland.

Name a thing that you have made yourself.
_____________________________________________________
How does the thing help you ?
_____________________________________________________
Suggest a way to improve it in future.
_____________________________________________________

MY WAY Science, Health and Physical Education - 5 145

Information
The gathered knowledge or data is
called information. Information can
take many different forms such as
words, numbers, pictures, sounds or
video.
The source from where we get information is called the source
of information. The different sources of information are books,
library, newspaper, radio, television, computer and internet.
The communication in which information is transferred in only
one way (one party) direction is called one way communication.
The communication in which information is transferred in two
way (both party) direction is called two way communication.
Can you write some examples of one way and two way
communication ?
One way communication ………………………………………....................
Two way communication ..…………………….......................................

Computer
You must be familiar with this word. Where do you see this word?
A computer is an electronic toolbox for working with information.
A computer is used to create documents, letters, drawings, etc.
A computer consists of two main elements: hardware (pieces of
equipment that make up a computer system) and software (the
instructions that a computer follows).
Computers enable us to process information and perform specific
tasks much more quickly that we can often do ourselves.

146 MY WAY Science, Health and Physical Education - 5

Quick Test 1: From your surrounding

Name two places where computers are used.
a. ______________________ b. _____________________
Write any two purposes of using computer.
___________________________________________________
___________________________________________________

Internet and email
The Internet consists of many
hundreds of computers and networks
all connected together by telephone
lines and cables. You can use the
internet to share information with
other users around the world.
Email refers to the way in which messages can be sent over
the internet. Email is much quicker than the traditional postal
system.
The information on the internet is stored in web pages and
websites.
A web page is like a normal page of text and pictures, but in a
special file format that any computer can read. There are millions
of web pages on the internet. To browse for information, you can
use a search engine to find quickly what you are looking for. One
very common example of search engine is www.google.com
Computers are in common use today as they can be used to process
large amount of data in a short amount of time. Many areas of
modern society take advantage of the power of computing.

MY WAY Science, Health and Physical Education - 5 147

Some of the common uses of the computer for home are:

 Playing computer/video games
 Word processing (writing letters),

doing homework (school, college,
university) etc.
 Emailing colleagues, friends and
relatives
 Searching for information or shopping on the internet

It is very important to have some computer skills in today’s
working world. Nowadays computer is used for storing student
details, names, addresses, academic records and so on, in most
schools.

Using a computer is generally safe; Did YOU know ?
however, there are a number of hazards
to avoid. Most of them arise if you use Gorkhapatra was made
the computer for long periods without a daily news paper in 1961.

break. Your eyes can get strained if you have been working on a
computer for a long time without taking a break. Look away from
the screen whenever you can and focus on objects further away
and remember to blink.

Quick Test 2: From yourself

1. Write your email address. ……………...…………………………….
2. How often do you email in a week ? ...…………………………..
3. Write the name of topic in Science you have recently

searched in the internet. …………………................................

148 MY WAY Science, Health and Physical Education - 5

Quick Test 3: All in one

True or False ? If false, correct it.

1. Email is much slower than the traditional postal system.
2. A computer consists of two main elements: hardware and

software.
3. It is not very important to have some computer skills in

today’s working world.
4. Email and Internet harm us.
5. Computers are common in use these days.

Work Further

Do the following activities : K

1. Fill in the blanks with the words given below. A
message/information/search engine/web page/ K

internet
a. Computer enables us to process ................... and

perform specific tasks much more quickly.
b. Email refers to the way in which ...................... can

be sent over the Internet.
c. The ........................ consists of many hundreds of

computers.
d. A ......... is like a normal page that anybody can read.
e. You can use a ............... to find information quickly.

2. Answer the following questions.
a. Computer is a useful device. Justify.
b. Is using a computer always safe ? Explain.
c. What are two important parts of a computer ?

MY WAY Science, Health and Physical Education - 5 149