Knowledge — learn English, learn the world
Why is the sky blue? What is VIBGYOR? Why do we yawn? 57 short reads in simple English, each with new words, a quick check and an “explain it” challenge. Two things at once: English and general knowledge.
Why is the sky blue?
Sunlight looks white, but it is really made of many colours mixed together — red, orange, …
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VIBGYOR — the colours of the rainbow
A rainbow has seven colours, always in the same order: Violet, Indigo, Blue, Green, Yellow…
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Why does ice float?
Most things get smaller and heavier for their size when they freeze. Water is strange: whe…
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Why do we see lightning before we hear thunder?
Lightning and thunder happen at exactly the same moment. Lightning is a giant electric spa…
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How do magnets work?
A magnet has two ends called poles: north and south. Opposite poles pull together, and the…
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Why does a heavy ship float but a small stone sinks?
A ship made of steel can weigh thousands of tonnes, yet it floats. A small stone weighs al…
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Why does the Moon change shape?
The Moon does not make its own light. It only reflects light from the Sun, like a mirror.…
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Why do stars twinkle?
Stars do not really twinkle. Out in space, they shine steadily. The twinkling happens in t…
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The eight planets
Our Sun has eight planets going around it. In order from the Sun: Mercury, Venus, Earth, M…
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What is a leap year?
The Earth takes about 365 and a quarter days to go around the Sun once. But our calendar y…
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Why are leaves green?
Leaves are green because they are full of a green substance called chlorophyll.…
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How does rain form? The water cycle
Rain begins in the sea, lakes and rivers. The Sun warms the water, and some of it turns in…
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Why is the sea salty?
Rivers taste fresh, yet they all flow into the sea — so where does the salt come from? Fro…
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How do birds fly?
Birds are built for flight from the inside out. Their bones are hollow and light, their ch…
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Why do coconut trees lean towards the sea?
Walk along any Kerala beach and you will see coconut palms leaning out over the water, as …
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Why do we yawn?
Everyone yawns — babies before they are born, dogs, cats, even fish. Yet scientists are st…
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Why do we dream?
Every night, for roughly two hours in total, your brain creates stories you did not ask fo…
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Why do onions make us cry?
Cutting an onion can make even a strong man cry. The onion is defending itself.…
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Why do we get goosebumps?
When you feel cold, or scared, or hear a song that moves you, tiny bumps rise on your skin…
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Why do we need sleep?
We spend about a third of our lives asleep. For most of history, people thought sleep was …
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Why is Kerala called ‘God’s Own Country’?
‘God’s Own Country’ is one of the most successful slogans in world tourism. It was created…
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How many languages does India speak?
Ask ‘how many languages are spoken in India?’ and you will get several correct answers, de…
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Why do we have time zones?
When it is noon in Kochi, it is early morning in London and the middle of the night in New…
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Which is the longest river in the world?
For many years, every textbook said the Nile. The Nile flows north through eleven African …
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Why does bread rise?
Flat dough goes into the oven and comes out as tall, soft bread. The helper is a tiny livi…
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How does your voice travel in a phone call?
You say ‘hello’ in Kochi and someone in Dubai hears it a fraction of a second later. In be…
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Why do we have day and night?
The Sun does not move around the Earth. The Earth spins, like a top, once every 24 hours.…
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Why do seasons change?
Many people think summer happens when the Earth is closer to the Sun. It is not. The Earth…
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What is a black hole?
A black hole is a place in space where gravity is so strong that nothing can escape — not …
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Why can’t we see stars in the daytime?
The stars are still there in the daytime. They never go away.…
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Why does a balloon stick to the wall after rubbing it on your hair?
Rub a balloon on your hair and press it to the wall. It stays there like magic. The magic …
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Why does popcorn pop?
A popcorn kernel is a tiny pressure cooker. Inside its hard shell is a little bit of water…
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What is an echo?
Shout in a big empty hall or near a hill and you hear your voice come back. That is an ech…
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Why does metal feel colder than wood?
Touch a steel spoon and a wooden spoon on the same table. The steel feels cold, the wood f…
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Why do bees make honey?
Bees make honey as food for winter and rainy days, when there are no flowers to visit.…
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How do fish breathe underwater?
Fish need oxygen just like us. But they do not breathe air — they take oxygen out of the w…
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Why do volcanoes erupt?
Deep under our feet, the Earth is so hot that rock melts. Melted rock underground is calle…
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Why do elephants have such big ears?
An elephant’s ears are not mainly for hearing. They are giant cooling fans.…
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Why do we get hiccups?
Under your lungs is a big flat muscle called the diaphragm. It moves down when you breathe…
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Why do fingers wrinkle in water?
Stay in the bath too long and your fingertips turn wrinkly. For years people thought the s…
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Why do we sneeze?
A sneeze is your nose’s way of cleaning itself.…
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Why is blood red?
Blood is red because of iron. Red blood cells are packed with a protein called haemoglobin…
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Why is Onam celebrated?
Onam falls in the Malayalam month of Chingam, in August or September, right after the mons…
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How did Kochi become a spice port?
For two thousand years, the pepper growing on Kerala’s hills was one of the most valuable …
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Where did the ₹ symbol come from?
Before 2010, the Indian rupee had no symbol. People wrote ‘Rs’. Dollars had $, pounds had …
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What do the colours of the Indian flag mean?
The Indian flag has three bands: saffron on top, white in the middle, green at the bottom.…
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Why does India drive on the left?
About a third of the world drives on the left, including India, the UK, Japan and Australi…
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Why can you float in the Dead Sea?
In the Dead Sea, between Jordan and Israel, you cannot sink. People float on their backs r…
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Why was the Great Wall of China built?
The Great Wall is not one wall but many, built over 2,000 years by different Chinese ruler…
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How does Wi-Fi work?
Wi-Fi is radio. Your router and your phone talk to each other using invisible radio waves,…
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How does a QR code work?
Every UPI payment in India starts with a square of black and white dots. That square is a …
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How does a touchscreen know where your finger is?
Your phone screen does not feel pressure. It feels electricity — yours.…
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How does GPS know where you are?
Above your head, about 30 GPS satellites circle the Earth, each carrying an atomic clock a…
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Who invented zero?
Counting is ancient, but the idea that ‘nothing’ deserves its own number is surprisingly n…
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Why are there seven days in a week?
Nothing in nature lasts seven days. A year is the Earth around the Sun; a month is roughly…
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Why are there 60 minutes in an hour?
We count in tens because we have ten fingers. So why is time counted in sixties?…
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What is a prime number, and why do banks love them?
A prime number can only be divided by 1 and itself: 2, 3, 5, 7, 11, 13 and so on. Every ot…
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