NCERT Solutions Class 6 Science Chapter 1 the Wonderful World of Science

F R E E S T U D Y M AT E R I A L F O R E V E R Y S T U D E N T

CLASS 6 · SCIENCE

NCERT Solutions

Chapter 1: The Wonderful World
of Science

NCERT Textbook — Curiosity

BOOK PAGES SECTIONS QUESTIONS MEDIUM

1–8 9 23 English

Solutions, notes, sample papers & more at 22 pages

Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

CLASS 6 · SCIENCE · CURIOSITY

NCERT Solutions — Chapter 1: The Wonderful World of
Science
Complete NCERT Solutions for Class 6 Science Chapter 1 The Wonderful World of Science from the NCERT
textbook Curiosity. Every question of the chapter — the three Activity 1.1, 1.2 and 1.3 “Let us think and
write” tasks and all the in-text questions from pages 1 to 8 — is answered with the observation, the reason
behind it and an everyday Indian example.

TEXTBOOK BOOK PAGES

Curiosity (Class 6) 1–8

SECTIONS QUESTIONS

9 23

MEDIUM

English

In-text Questions — Page 1
Chapter opening — What is Science?

Q1 Did you enjoy discovering and exploring the world around you in the Preparatory
Stage of school?

Yes. In the Preparatory Stage (Classes 3, 4 and 5) we learnt through Our Wonderful World and
The World Around Us — and almost all of it was discovery rather than memorising.

We observed — the shapes of leaves, the ants marching in a line, the Moon changing shape
night after night.
We collected and sorted — seeds, pebbles, feathers, pictures of animals and birds.
We did things with our hands — grew gram seeds on wet cotton, made a paper windmill,
floated and sank things in a bucket of water.
We talked to people — asked grandparents about the games and food of their childhood,
visited the market and the post office.

Why the book asks this: the chapter wants you to notice that you have already been
doing science. In the Middle Stage the same curiosity continues, but now it gets a
name — Science — and a proper step-by-step method.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Try This: Write down three things you discovered by yourself in Class 5 that
surprised you. Keep the list — by the end of Class 6 you will be able to explain most
of them.

Q2 What is Science?

In the words of the textbook:

Science is a way of thinking, observing and doing things to understand the world we live

in and to uncover the secrets of the universe.

So science is not a fat book of facts to be learnt by heart. It is a way of working. Break the
definition into its three parts:

Thinking — asking questions, making guesses, reasoning about what the answer could be.
Observing — looking carefully at things around you and noticing what actually happens.
Doing — trying things out, experimenting, testing whether your guess is right.

The book compares science to two things:

A big adventure — we ask questions, explore and try to understand how things work.
A giant, unending jigsaw puzzle — every discovery adds one more piece. Sometimes we
find a piece was put in the wrong place and has to be moved. That is why new discoveries
keep changing our understanding of the world.

Why the puzzle never ends: every new piece of knowledge raises fresh questions.
Knowing that water boils does not stop us — we then ask at what temperature, and
why it boils sooner on a hill. So there is no limit to what can be discovered.

Did you know? The most important tool a scientist has is not a microscope or a
telescope — it is ‘Curiosity’. That is why this textbook is named Curiosity.

Q3 Have you ever looked up at the night sky and wondered why the stars shine?

Yes — and this is a perfect example of a question that begins with simple observation.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

What you observe: on a clear, dark night, away from street lights, thousands of tiny points of
light are seen. They twinkle, and some look brighter than others. The Moon, by contrast, does
not twinkle.
Why it happens:

A star gives out its own light. Deep inside a star, matter is packed so tightly and is so hot
that it releases enormous amounts of heat and light. Our Sun is also a star — the nearest
one — which is why it looks like a huge ball of fire and the others look like pinpricks.
Stars look tiny only because they are unimaginably far away.
They seem to twinkle because their light passes through the moving layers of air around the
Earth, which bend the light a little this way and a little that way. The Moon and planets are
much closer and look like small discs rather than points, so their twinkling is not noticed.

Where this helps in daily life: Indian sailors and travellers used the Dhruva tara
(Pole Star) to find north long before compasses and GPS existed. Farmers still fix the
times for sowing and for festivals such as Makar Sankranti using the positions of
stars and the Sun.

Check it yourself: On a moonless night, look at the sky first from your street and
then from a dark field or terrace with the lights off. Many more stars appear in the
dark place. Light from our own lamps is what hides them — this is called light
pollution.

Q4 Or watched a flower bloom and wondered how it knows when to open?

Yes — flowers really do open and close at fixed times, and it is not an accident.
What you observe: a lotus and a sunflower open in the morning sunlight and close by evening.
Raat ki rani and the brahma kamal do the opposite — they open after dark. Tamarind and rain-
tree leaflets fold up at night.
Why it happens: a plant has no eyes or brain, but it can still sense its surroundings.

The petals respond to light and darkness, and to the rise and fall of temperature between
day and night. One side of the petal grows or swells with water a little faster than the other,
so the petal bends outward and the flower opens.
Plants also have an inner “body clock” of roughly 24 hours, so they begin to open a little
before the sunlight actually arrives.
The timing is useful to the plant. Day-blooming flowers open when bees and butterflies are
active; night-blooming flowers open when moths and bats are about, and they are usually
white and strongly scented so that these visitors can find them in the dark.

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Class 6 Science Chapter 1 The Wonderful World of Science
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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

The most important idea on this page: as we discover more and more, we start
realising that all these ideas are connected. Rain is about water and heat; food is
about plants and materials. Science is one subject, not eight separate lists.

Q2 How do these plants and animals grow?

Every living thing grows by taking in food, using it to build new parts of its body, and
adding cells little by little. But plants and animals do it in different ways.

PLANTS ANIMALS

Where the food They make their own food in their green They cannot make food; they eat plants or
comes from leaves using sunlight, water from the soil and other animals.
air.

What else is Water, air, sunlight, minerals from the soil, Food, water, air, warmth, shelter
needed warmth

How growth Roots go deeper, stem gets taller and Body becomes longer, taller and heavier;
shows thicker, new leaves, flowers and fruits some animals change form completely
appear

When it stops Many plants keep growing all their life Most animals stop growing once they
become adults

What you can observe: the two pictures in your book show it beautifully.

A seed soaks up water, splits open, sends a root down and a shoot up, and becomes a young
plant.
A caterpillar eats leaves greedily, grows, then rests inside a case and finally comes out as a
butterfly. Such a complete change of form is called metamorphosis.

Why growth needs food: a body cannot make new parts out of nothing. Food
supplies both the raw material for the new parts and the energy needed to build
them — exactly as a mason needs both bricks and strength to raise a wall.

Try This: Soak five gram (chana) seeds overnight, keep them on wet cotton in a bowl
and place it near a window. Measure the shoot with a scale every morning for a
week and draw a small chart. You will have observed growth with your own eyes.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Q3 Across the country, we have different cuisines with their many tasty dishes. What
are they made of? How do we find out?

What they are made of: however different two Indian dishes look, they are built from the same
small set of food components.

COMPONENT WHAT IT DOES FOR US INDIAN FOODS RICH IN IT

Carbohydrates Give energy rice, chapati, potato, jaggery

Proteins Build the body and repair it dal, rajma, paneer, egg, fish

Fats Give a lot of energy and store it ghee, mustard oil, groundnut,
butter

Vitamins and Protect us from diseases; make bones amla, guava, spinach, milk, banana
minerals and blood

Dietary fibre and Keep digestion smooth salad, whole grains, fruits, drinking
water water

How we find out — by testing, not by guessing. Simple tests you will do later in this book:

Starch test — put a drop of iodine solution on a bit of boiled rice or potato. It turns blue-
black if starch is present.
Fat test — rub the food on a piece of paper and let it dry. An oily patch that lets light
through means fat is present. Try it with a peanut and with a piece of apple, and compare.
Protein test — a few drops of copper sulphate solution and caustic soda solution on a food
paste give a violet colour if protein is present.

Why this matters in an Indian kitchen: a plate of only rice gives energy but not
enough body-building material. That is why a traditional thali pairs rice or roti with
dal (protein), a vegetable (vitamins and minerals), curd (protein and calcium) and a
little ghee (fat). Our grandmothers arrived at a balanced diet long before the tests
were invented — the tests only explain why it works.

In-text Questions — Page 4

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Water, heat and the materials around us

Q1 Do you ever wonder why and how it rains?

Yes. Rain is the visible part of the water cycle, which runs all the time between the sea, the sky
and the land.
How it happens — step by step:

1. Evaporation. The Sun heats the water of oceans, rivers, lakes and even wet clothes. Water
slowly changes into an invisible gas called water vapour and rises with the warm air.
2. Cooling as it rises. Higher up, the air is colder.
3. Condensation. The vapour cools and turns back into tiny droplets of water around specks
of dust. Millions of such droplets floating together are what we see as a cloud.
4. Precipitation. The droplets keep joining one another until they become too heavy for the air
to hold — and they fall as rain. If it is very cold high up, they fall as hail or snow.
5. The rain flows into rivers and back to the sea, and the whole cycle begins again.

Why the rain comes at a fixed season in India: in summer the land heats up much
faster than the Arabian Sea and the Bay of Bengal. Hot air over the land rises, and
moist air rushes in from the sea to take its place. These are the monsoon winds.
When they strike the Western Ghats and the Himalayas they are forced upward, cool
down, and pour rain — which is why Kerala gets the first showers around June and
Cherrapunji (Meghalaya) is one of the wettest places on Earth.

Check it yourself: Hold a cold steel glass of water in a room on a humid day. Water
drops appear on the outside of the glass. Nothing leaked out — the vapour already
present in the air condensed on the cold surface. That is exactly how a cloud is born.

Q2 Have you noticed that water freezes and becomes ice when we cool it and boils and
becomes steam when we heat it?

Yes. Water is the same substance in all three forms; only its state changes.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

STATE WHAT WE CALL IT WHAT MAKES IT CHANGE EVERYDAY SIGHT

Solid Ice Cooling to 0 °C — freezing ice cubes in the freezer, hailstones

Liquid Water Warming ice above 0 °C — melting a glass of drinking water

Gas Steam / water vapour Heating to 100 °C — boiling the whistle of a pressure cooker

Why it happens: water is made of extremely tiny particles that are always moving.

When water is cooled, the particles slow down, come close, lock into fixed places
and can only shake where they are. The water becomes hard — ice.
When water is heated, the particles move faster and faster until they break free
of one another and fly apart into the air — steam.

So heating and cooling do not create a new substance; they only change how freely
the particles can move. That is why melting ice gives back exactly the same water.

Did you know? The white cloud you see coming out of a cooker or a kettle is not
steam. Real steam is invisible. What you see is steam that has already cooled a little
and turned back into tiny water droplets — condensation happening right in front of
you.

Everyday use in India: a matka (earthen pot) keeps water cool in summer because
water seeps through its tiny pores and evaporates, taking heat away from the pot.
Sprinkling water on a terrace before a summer evening cools it for the same reason.

Q3 How do we understand hot and cold?

By touch we can only compare — to know exactly how hot something is, we must measure
it.
What you observe: our sense of touch is unreliable. Try this simple test:

Left hand → bowl of cold water | Right hand → bowl of warm water

After a minute, put both hands into the same bowl of ordinary water.

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Class 6 Science Chapter 1 The Wonderful World of Science
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The same water feels warm to the left hand and cool to the right hand at the same moment.
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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

OBJECT MATERIAL PROPERTY THAT MAKES IT SUITABLE

Paper wood pulp light, soft, holds ink

Key metal (brass, steel) hard, strong, does not bend or break

Ruler plastic light, stiff, cheap, does not rust

Eraser rubber soft and springy, rubs off pencil marks

Magnet on the magnetic material attracts iron, so the lid snaps shut
box

Clothes cotton, wool, silk, synthetic cotton lets air through in summer; wool traps air and
fibre keeps us warm

Cup glass, ceramic, steel or clay holds liquid, does not dissolve in milk

How we separate materials: we look for one property that only one of the materials has, and
then use it.

Handpicking — for large, few, clearly different pieces, such as stones from rice.
Winnowing — a farmer drops the threshed grain in the breeze; the light husk is blown away
and the heavy grain falls straight down.
Sieving — flour passes through the holes of a chalni, bran stays back.
Magnetic separation — a magnet pulls out iron pins from a heap of sand or pencil
shavings.
Filtration — tea leaves stay in the strainer while the tea passes through.
Sedimentation and decantation — muddy water is left standing, the mud settles and the
clear water is poured off.
Evaporation — sea water is spread in shallow pans; the water evaporates in the Sun and
common salt is left behind. This is how salt is made along the coasts of Gujarat and Tamil
Nadu.

The rule behind all of them: separation always uses a difference in a property —
size for sieving, weight for winnowing, attraction to a magnet for magnetic
separation, solubility and boiling behaviour for evaporation. If two materials share
every property, they cannot be separated.

In-text Questions — Page 5

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Finding answers on our own — the pen that stopped writing

Q1 How can we try to find answers to our questions on our own?

By following the scientific method — a short, honest routine you can use on any puzzle, big or
small.

Observe → Question → Guess → Test → Analyse

1. Observe carefully. Note exactly what is happening, without deciding the cause yet.
2. Frame a clear question. “Why does…?” or “How does…?” A vague question gives a vague
answer.
3. Make a guess that could explain it — and make sure it is a guess you can actually check.
4. Test the guess by an experiment, a measurement, or more observation.
5. Analyse the result. If the guess is proved right, you have your answer. If it is proved wrong,
that is not a failure — make a new guess and test again.

Why this works better than simply believing: anyone can claim anything. A guess
that has passed a test is evidence-based, and someone else can repeat the same
test and get the same result. That is what makes a scientific answer trustworthy.

Tip: When you cannot test something at home, use the other tools of a scientist —
read a reliable book, look it up carefully, ask your teacher, and above all discuss it
with friends. The chapter reminds us that science is rarely done alone.

Q2 Suppose your pen stops writing. What would you do?

I would not just throw the pen away — I would find out why it stopped, exactly as the book
describes.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

STEP WHAT I DO WITH THE PEN

Observe The pen moves on the paper but no line appears.

Question “Why did my pen stop writing?”

Guess “Perhaps the ink is finished.”

Test Open the pen and look at the ink refill.

Analyse If the refill is empty, the guess was correct — the ink had finished.

Why this counts as science: notice that at no point did I simply assume the ink was
over. I made it a guess and then checked it. Guess + check is the heart of the
scientific method, and you have been doing it for years without calling it that.

Q3 But suppose you found that the ink was not finished. Now what would you do?

Then the first guess is wrong — and that is perfectly normal in science. I would make a new
guess and test that one too.

New guess 1 — the ink has dried up at the tip. Test: dip the nib in a little warm water or
scribble hard on rough paper. If it starts writing, the guess was right.
New guess 2 — the ball at the tip is stuck or dirty. Test: clean the tip and roll it on paper. If
it works now, this was the reason.
New guess 3 — there is an air bubble in the refill. Test: flick or shake the refill downwards
so the ink moves past the bubble.
New guess 4 — the refill is cracked or the nib is bent. Test: put the same refill in another
pen body. If it still fails, the refill is at fault; if it writes, the body was the problem.

Why a wrong guess is useful: every test that fails removes one possible cause and
brings you closer to the real one. Scientists do exactly this. In fact the chapter says a
piece of the jigsaw puzzle sometimes has to be moved — being proved wrong is how
science moves forward, not a reason to stop.

Tip: Change only one thing at a time while testing. If you clean the tip and change
the refill together and the pen writes, you will never know which of the two was the
cause.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Activity 1.1: Let us think and write — Page 5
A problem you solved yourself

ACTIVITY

Q1 Write about a similar problem that you tried to solve.

This is your own experience, so write about a real problem from your life. A good answer must
contain three things: what went wrong, what you thought the reason was, and how you
checked.
Choose a problem from home or school, for example:

The cycle became hard to pedal.
The TV remote stopped working.
The tubelight flickered but did not glow.
The plant on the window sill dried up even though it was watered.
The tap in the kitchen gave only a thin trickle of water.

Sample answer: One morning my bicycle became very hard to pedal, though
nothing looked broken. I first guessed that the chain had become dry, so I looked
at it — it was oiled and moved freely, so that guess was wrong. Next I guessed that
the rear tyre had less air. I pressed both tyres with my thumb: the front one was
firm but the rear one sank in easily. I filled air at the shop near my school and the
cycle ran smoothly again. My second guess was correct.

What makes this a good answer: it names one clear problem, states the guesses
before the checking, admits that the first guess failed, and ends with the evidence
that settled the matter — not just “I fixed it”.

Q2 What steps did you take?

Write your steps in order, and then match them with the five steps of the scientific method. For
the cycle example above:

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Class 6 Science Chapter 1 The Wonderful World of Science
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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

1. Observe Notice something interesting or puzzling.

2. Question Wonder about it and frame a clear “why?” or “how?”

3. Guess Think of a possible answer to that question.

4. Test Check the guess by experiments or more observations.

5. Analyse See whether the result really answers your question.

The five steps of the scientific method, as printed on page 6 of Curiosity. If step 5 shows the guess
was wrong, you go back to step 3 and guess again.

In the book's own words:

1. First, we observe something that we find interesting or we do not understand.
2. This makes us wonder and perhaps think of a question about it.
3. Then, we guess a possible answer to that question.
4. We test this guess through experiments or more observations.
5. We then try to analyse the results to see if it actually answers our question.

Why the order matters: the guess must come before the test, and the test must be
able to prove the guess wrong. If you decide the answer first and then look only for
things that agree with you, you are not doing science. The loop from step 5 back to
step 3 is what keeps the method honest.

Did you know? Science is not only memorising facts and figures, and it is not only
doing experiments. The book says clearly that it is about following a step-by-step
process to find answers.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Q2 Do you now realise that there are several daily-life situations where we knowingly
or unknowingly apply the scientific method?

Yes. Once you know the five steps, you start spotting them everywhere. The chapter itself gives
three examples, and there are dozens more at home.

PERSON OBSERVATION QUESTION GUESS TEST

Cook Dal has spilled out of Why did it spill? Too much Cook the same dal with
the cooker water was put less water and watch
in

Cycle The tyre is flat From where did the There is a Fill the tube with air,
repairer air leak out? hole in the dip it in water and look
tube for bubbles

Electrician The bulb does not Is the fault in the bulb The bulb is Fit the same bulb in
glow or the switch? fused another working holder

You The mobile is not Is it the charger, the The cable is Use a different cable in
charging cable or the socket? broken inside the same socket

The chapter's big message: “Scientists are people who follow the scientific
method… but anyone who follows the scientific method is working like a
scientist.” A scientist is not defined by a laboratory coat but by the way of thinking.
When we ask questions and find out answers, we are all, in a way, scientists.

Why we should still learn science: we all use the method a little, on small
problems. Learning science trains us to use it well — on bigger problems such as
cleaning a polluted river, growing more food, or curing a disease.

Activity 1.2: Let us think and write — Page 6

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

The scientific method in daily life

ACTIVITY

Q1 Describe a daily life situation where you think someone was following a scientific
method.

Pick any real incident you have seen, and describe it in the five steps. What your answer must
show is that the person guessed first and then checked.

Sample answer: Last month our ceiling fan started making a loud noise. My
father first guessed that a blade had become loose. He switched the fan off,
climbed a stool and tried to move each blade — all three were tight, so that guess
was wrong. He then guessed that dust and grease had collected in the fan and
were unbalancing it. He wiped the blades clean with a wet cloth and put a few drops
of oil where the blades meet the body. When the fan was switched on, the noise had
gone. His second guess was proved correct.

Other situations you could write about:

The milk boiled over — was the flame too high, or the vessel too small?
The curd did not set in winter — was the milk too cold when the culture was added?
The mobile phone kept discharging fast — was it the battery, or an app running in the
background?
A plant kept in a corner turned yellow — was it too little sunlight, or too much water?
The water pump did not start — was the fault in the switch, the wire or the motor?

What to look for in each case: the person did not accept the first thought as final.
They stated a possible cause, arranged a way to check it, and were ready to change
their mind. That readiness to be proved wrong is the real mark of the scientific
method.

Activity 1.3: Let us think and write — Page 7

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Asking “Why?”

ACTIVITY

Q1 If you have to ask “Why?” about something, what would you ask about?

Choose something you have actually seen with your own eyes — a “why” about your own
surroundings is always better than one copied from a book.
Good questions you could ask:

Why does the sky look blue in the day and red at sunset?
Why does a slice of apple turn brown after some time, but a slice of lemon does not?
Why do sunflowers turn to face the Sun?
Why does an earthen matka keep water cool without any electricity?
Why do ants always walk in a single line?
Why does a wet floor dry faster when a fan is on?
Why does the Moon appear to change its shape through the month?
Why does a puri swell up in hot oil?

Sample answer: I would ask, “Why does a cut apple turn brown when it is left on
the plate?” I have seen this every time my mother cuts an apple, and the brown
colour appears only on the cut surface, not on the skin.

What makes a question a good scientific question: it should be about something
you can observe, it should be specific (not “why is the world like this?”), and it
should be possible to test at least partly by yourself. “Why does a cut apple turn
brown?” passes all three tests.

Q2 Try to write down how you would attempt to find an answer to your question.

Write your plan as the five steps of the scientific method. Continuing the apple question:

Page 18 of 22

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a g l Page 19 of 22

Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

A person who only memorises can repeat facts, but is stuck the moment a new situation
appears.
A person who asks “why” understands the reason behind the fact, and can therefore use it in
a situation nobody taught them about.

Why this is the right note to end on: the whole chapter has argued that science is
a way of working, not a body of information. Curiosity starts the process, the
question directs it, and the test settles it. Drop the “why” and the whole method
collapses.

Try This: Keep a “Why Notebook”. Every day write down one thing that puzzled you
— and leave space to fill in the answer when you find it. By the end of Class 6 you
will be surprised how many blanks you have filled in yourself.

Q2 Are you ready to embark upon the exciting journey of science?

Yes! And the chapter tells us exactly what to carry on the journey:

Curiosity — never stop wondering about the mysteries of the universe.
Keen observation — the chapter says the first and foremost thing is to be curious and to
observe your surroundings keenly.
The scientific method — observe, question, guess, test, analyse.
Friends — “science is rarely done alone.” Scientists across the world work together in large
teams, so if you cannot find an answer yourself, ask your friends to help you out.
Patience — you will not find answers to all your questions in Grade 6, and that is fine. This
journey runs for the next five years and even beyond.

The picture on this page explains the mood: children running happily in the rain.
Science, says the book, is joyful exploration — not a burden to be carried but
something to enjoy. The world is full of things we do not know, waiting to be
explored.

Did you know? Every chapter that follows is an answer to a question already asked
in this chapter — living things, food, water, heat, materials, motion, light, and the
Sun, the Moon and the stars. Chapter 1 is the map; the rest of the book is the
journey.

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Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Chapter at a glance
Science is a way of thinking, observing and doing things to understand the world we live in
and to uncover the secrets of the universe. It is not just a pile of facts to be memorised.
The engine of science is curiosity — the habit of asking “how?” and “why?” about ordinary
things. That is exactly why this Class 6 textbook is called Curiosity.
Science is everywhere — in a grain of sand and in a mountain, in the kitchen and on the
playground, at the bottom of the ocean and in a far-away galaxy.
The scientific method has five steps: observe → question → guess → test → analyse. If
the guess fails the test, you make a new guess and test again.
A scientist is anyone who follows this method — a cook wondering why the dal spilled out
of the cooker, a cycle repairer hunting for an air leak, an electrician checking a bulb and a
switch.
This book will explore planet Earth and its environment, living things, food, water, heat,
materials, motion, light and even the Sun, the Moon and the stars. Science is done
together, so ask your friends when you are stuck.

Page 21 of 22

Class 6 Science Chapter 1 The Wonderful World of Science AglaSem · NCERT Solutions

Quick revision

TERM WHAT IT MEANS WHERE IT COMES EVERYDAY EXAMPLE
IN THE CHAPTER

Science A way of thinking, observing and doing Page 1 Finding out why stars
things to understand the world and uncover shine
the secrets of the universe

Curiosity The urge to ask questions about whatever you Page 1 Wondering how a
see — and the title of this book flower knows when to
open

Observation Looking or noticing carefully, without Step 1, page 6 Seeing dal spilled
guessing yet around the cooker

Question Turning what you noticed into a clear “why?” Step 2, page 6 “Why did my pen stop
or “how?” writing?”

Guess A possible answer thought of before testing Step 3, page 6 “Maybe the ink is
(hypothesis) finished.”

Test / Doing something, or observing more, to Step 4, page 6 Opening the pen and
experiment check the guess checking the refill

Analysis Studying the result to see if it really answers Step 5, page 6 Refill empty → the
the question guess was right

Scientific The step-by-step process observe → question Page 5 A cycle repairer dipping
method → guess → test → analyse a tube in water

Scientist A person who follows the scientific method Page 6 Anyone who asks and
to solve problems or discover new things tests — even a cook

Spirit of The habit of never stopping asking questions Pages 5 and 8 “To be a wise person,
inquiry be a whys person!”

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