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Electricity & magnets

Charge, current, and the pull of a magnet — 32 tiny stories across 6 shelves.

How things work

Everyday machines, taken apart — 20 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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Electricity needs a full loop

Why Does a Switch Turn Things On?

Electricity only flows around an unbroken loop, so a few millimetres of air anywhere in that loop stops every last bit of it at once.

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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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A circuit that completes itself

What Happens When You Press a Doorbell?

The button is not the bell. It is a gap in a circuit your finger closes, letting current turn a coil into a magnet that swings a hammer.

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Something has to break first

Why Do Fuses Blow?

A fuse is the weakest part of a circuit on purpose: a thin wire that melts before the cable behind it can ever get hot enough to burn.

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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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Steam that flips a switch

Why Does a Kettle Switch Itself Off?

Steam runs down a hidden tube to a strip of two bonded metals, which bends as it warms until it snaps the power off behind your back.

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Rows and columns, checked constantly

How Does a Keyboard Know Which Key You Pressed?

No wire runs from every key. They are wired as a grid and scanned hundreds of times a second, so twenty wires find one key among a hundred.

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A wire too hot to stay dark

How Does Electricity Become Light?

Only the filament is thin, so the current squeezes there and pours out white light near 2,500°C. An LED skips the heat entirely.

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A speaker running backwards

How Does Your Voice Get Recorded?

A membrane thinner than paper flexes when your voice hits it, and that movement is measured thousands of times a second into a list of numbers.

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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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A magnet shoving paper

How Does a Speaker Make Sound?

A coil carrying the recorded current becomes a magnet, dragging a paper cone in and out so it shoves the air at exactly that rhythm.

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Sound turned into electricity and back

How Does a Voice Travel Down a Wire?

A telephone turns the air's vibration into a matching electrical wobble, sends that down a wire, and turns it back into sound.

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It notices charge, not pressure

How Does Glass Feel Your Finger?

A touchscreen never notices pressure. It measures charge draining into the salty water you are made of, at every crossing of a wire grid.

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A wire loop under the tarmac

How Does the Road Know You Are Waiting?

The saw cuts in the road just before the stop line hold a loop of wire whose field changes when metal parks over it. A bicycle barely disturbs it.

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Not through the sky

The Internet Runs Along the Sea Floor

About 99 per cent of international internet traffic crosses the ocean floor by fibre-optic cable rather than satellite — and ships have laid it since 1858.

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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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Physics

Invisible forces you can play with — 4 stories.

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What things are made of

Atoms, metal, glass, plastic, and every kind of stuff — 3 stories.

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Earth & sky

Weather, light, and the air around us — 2 stories.

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Everyday wonders

Kitchen, bubbles, echoes, and odd little magic — 2 stories.

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Space

Crashy night-sky stories — 1 story.

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