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Energy

Fuel, power, and where the go comes from — 58 tiny stories across 8 shelves.

Physics

Invisible forces you can play with — 13 stories.

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Passing motion along

What Happens When Things Crash?

Motion is never destroyed in a crash, only handed over. What decides the damage is not the speed itself but how long the stop is allowed to take.

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Jostling passed along

Why Does a Metal Spoon Get Hot?

No atom ever travels along the spoon; each stays put and passes the jiggle on. Metal feels cold only because it pulls heat out of your hand fast.

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It never goes anywhere

Where Does Energy Go When Things Stop?

Energy is never used up when something stops. It has only changed form, and every change spills a little as heat that is hard to use again.

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Everything is shaking

What Is Heat?

Heat is not a substance you add. It is how fast the atoms are jiggling, which is why a thermometer is really a gauge of atomic speed.

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Nothing changes for free

Why Do Things Keep Moving?

An object keeps doing exactly what it was doing until something makes it stop. Every change of speed or direction has to be paid for with a force.

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It makes nothing — it slows

Does a Coat Make You Warm?

A coat makes no heat of its own. It traps still air, which slows the escape of the warmth your body is already producing every second.

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Light marching in step

What Makes a Laser Different From a Torch?

A torch throws every colour every way with the waves unrelated. A laser is one colour, one direction, and every wave stepping in time.

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Mass times speed

Why Are Heavy Things Hard to Stop?

Nothing is lost when things collide: what one object loses another gains. Airbags, crash mats and bent knees simply make the stop take longer.

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Newton's third law

Every Push Has a Push Back

You cannot push anything without it pushing back exactly as hard. That pair of forces is what makes walking, swimming and flying possible at all.

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Pushing in time

Why Does One Note Rattle the Window?

Every object has a rhythm it swings at naturally. A sound matching that rhythm adds a push on every swing, so tiny pushes build into a rattle.

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Air, pushed

How Does Sound Travel?

Sound is not a thing that flies. It is a squeeze handed from one air molecule to the next, passed all the way along to your eardrum.

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Storing a push

How Do Springs Work?

A spring stores the work you put into squashing or stretching it, then hands that energy straight back as it returns to its own shape.

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About a hundred watts of it

You Are Glowing Right Now

Warm objects radiate light whose colour depends on their temperature — yours is infrared, invisible to us and perfectly obvious to the right camera.

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How things work

Everyday machines, taken apart — 13 stories.

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A sealed tank of chemicals

Why Does a Battery Run Out?

A battery stores reacting chemicals rather than electricity, and that reaction can only happen a fixed number of times before it is spent.

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A shove converted to a spin

How Does a Bang Turn a Wheel?

Burning fuel shoves a piston down a tube, and a crankshaft bends that straight shove into the round motion the wheels actually need.

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Someone else's computer, in a shed

Where Is the Cloud?

The cloud is not in the sky. It is racks of computers in big cooled buildings, holding copies of your files and a vast electricity bill.

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Rain, stored on a hillside

How Does a Dam Make Electricity?

A dam is a battery filled by the weather: it holds rain high up and lets it fall through a turbine, turning the height it loses into power.

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Oil that refuses to be squashed

How Does a Digger Lift So Much?

Oil cannot be squashed, so pressure from a small piston reaches a much larger one, which pushes proportionally harder. That is the whole arm.

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Only lifting the difference

Why Does a Lift Need a Counterweight?

A counterweight balances almost all of the car, so the motor only ever lifts the difference between the two — a small fraction of the whole load.

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A magnet, some wire, and movement

How Is Electricity Actually Made?

Every generator on Earth does one thing: it moves a magnet past coils of wire. Run the same machine backwards and it is a motor instead.

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Splitting atoms to boil a kettle

How Does Nuclear Power Work?

A nuclear station is an ordinary steam power station with a very strange fire: split atoms make the heat, control rods hold the rate steady.

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Three pins, three different jobs

What Is Happening Inside a Plug?

A plug has several pins because electricity needs a way in, a way back, and an escape to the ground, plus a fuse designed to fail on purpose.

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Pushed hard so less is lost

Why Are Power Lines So High Up?

Power lines carry electricity at enormous voltage because that wastes far less on the journey, then transformers step it back down.

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Almost all of them boil water

How Does a Power Station Work?

Coal, gas and nuclear stations look nothing alike and all do one thing — boil water, so the steam spins a magnet inside coils of wire.

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Light knocking electrons loose

How Does Sunlight Become Electricity?

Each packet of sunlight can knock one electron loose, and a solar cell is layered so that every freed electron flows the same way out.

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Three blades, and each one is a wing

How Does a Wind Turbine Work?

A turbine blade is not pushed by the wind, it is lifted sideways like a wing — and no turbine can take more than two-fifths of the wind's energy.

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Life & body

Seeds, hearts, senses, and growing things — 10 stories.

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Four things in a river

What Is Blood Made Of?

Blood is mostly salty water carrying three cargoes: red cells that ferry oxygen, white cells that stand guard, and fragments that plug the leaks.

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Fetching oxygen, dumping waste

Why Do We Breathe?

Breathing collects the oxygen that releases energy from food and dumps the carbon dioxide left over. The urge to breathe comes from the waste, not the air.

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The colour it refuses

Why Are Leaves Green?

Green is the one colour chlorophyll cannot use, so it is thrown back at you. The yellows sit underneath all summer, until autumn strips the green away.

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Demand outrunning supply

Why Does Exercise Make You Puff?

Working muscles burn oxygen far faster than resting ones, so breathing and heart rate climb to keep up. Puffing is the delivery system catching up.

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Energy passed along

Who Eats Whom?

Every step of a food chain spends about 90% of its energy simply living, so a tenth passes upward. After four or five links there is nothing left.

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The food is the small part

What Gets Wasted When Food Is Thrown Away?

Throwing away a sandwich wastes the field, the water, the fuel and the year behind it — and about a third of all food grown is never eaten.

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Only ever pulling

How Do Muscles Move You?

Muscles can only pull, never push, so they come in opposing pairs and use bones as levers to turn a short pull into a much larger movement.

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Building food from air

How Do Plants Eat Light?

Plants build sugar out of air, water and light. A tree is made mostly of air — its carbon comes from carbon dioxide, not from the soil it stands in.

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Muscles working for the heat, not the movement

Why Do You Shiver When You Are Cold?

Shivering makes your muscles do deliberately useless work, because a muscle is a poor engine and most of its effort comes out as heat anyway.

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Taken apart, then absorbed

What Happens to Food You Eat?

Nothing is absorbed until it is molecule-sized. Acid unravels proteins, but the real work happens in seven metres of small intestine folded very small.

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What things are made of

Atoms, metal, glass, plastic, and every kind of stuff — 8 stories.

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Light, cheap to reuse, and it protects itself

Why Are Drink Cans Made of Aluminium?

Aluminium is light, does not rust because it seals itself, and can be recycled with a fraction of the energy it took to make.

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Burning wood twice

Why Does Charcoal Burn Hotter Than Wood?

Charcoal is wood already half burned: baked without air until only carbon remains, so everything that would have made smoke has gone.

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Loose electrons, and a price that works

Why Are Wires Made of Copper?

Silver conducts slightly better, yet almost every wire is copper: its outer electrons drift free, and it wins on price and on bending.

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Sunlight from a very long time ago

What Is Crude Oil?

Crude oil is the squashed remains of tiny sea creatures, cooked under rock — so burning it releases sunlight caught a hundred million years ago.

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Millions of small links, joined into chains

What Is Plastic Actually Made Of?

Heating lets the chains slide without breaking, so plastic can be moulded again — but different chains refuse to mix, which is why sorting matters.

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Melting versus mashing

Why Does Glass Recycle Better Than Paper?

Melting rebuilds glass and metal exactly, but tearing paper apart shortens its fibres a little each time, so paper eventually runs out of lives.

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The wick drinks its own fuel

Why Does a Candle Burn for Hours?

The wick is not the fuel and solid wax will not catch: the flame melts the wax, the wick lifts it, and what actually burns is the vapour.

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Glowing gas, not glowing wood

What Actually Is a Flame?

A flame is not the wood burning. It is gas driven out of the wood by heat, glowing as it meets oxygen — which is why heat, air or fuel each put it out.

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Space

Crashy night-sky stories — 5 stories.

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Earth & sky

Weather, light, and the air around us — 4 stories.

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Everyday wonders

Kitchen, bubbles, echoes, and odd little magic — 3 stories.

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Animals

Creatures on land, in the sea, and in the air — 2 stories.

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