What Is a Magnetic Field, and Why Can’t We See It?
A magnetic field is the invisible space around a magnet where its push and pull can reach. You cannot see it, because it is not made of light or of anything you can touch. But we can see what it does!
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Why Do Magnets Have Two Ends Called Poles?
Every magnet has two poles, called north and south. They are the places where its pulling power is strongest. Every magnet has exactly two poles.
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Why Do Opposite Poles Attract but Matching Poles Push Apart?
Opposite poles pull together, but matching poles push apart. The secret is in the direction of a magnet's field. Electric charges follow a similar rule: opposite charges attract.
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What Happens If You Cut a Magnet in Half?
If you cut a magnet in half, you do not get a north piece and a south piece. You get two smaller magnets, and each one has its own north and south pole!
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Why Is a Magnet’s Pull Strongest at Its Ends?
A bar magnet pulls hardest at its two ends and weakest in its middle. That happens because of what the tiny groups inside are doing.
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How Far Away Can a Magnet Reach?
A magnet's field never stops all at once, but it fades very quickly with distance. A small fridge magnet might only reach a paper clip a few inches away.
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Why Can a Magnet Work Through Paper, Water, and Even Your Hand?
A magnetic field passes right through most things that are not magnetic. That includes paper, plastic, wood, glass, water, and even your skin.
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What Are Magnetic Field Lines?
Magnetic field lines are imaginary curved lines that scientists draw. They show the shape and direction of a magnetic field. Think of them as a map of the invisible.
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How Can Iron Filings Show the Shape of a Magnet’s Field?
Iron filings are tiny slivers of iron, like very fine metal dust. Around a magnet, they line up to draw the shape of its field. Photographs of iron-filing patterns have helped people understand magnets since the 1800s.
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How Can a Magnet Turn a Paper Clip Into a Tiny Magnet?
Paper clips are steel, and steel has iron in it. Next to a magnet, it can become a tiny magnet itself! A paper clip is made of steel, which contains iron.
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What Tiny Neighborhoods Inside Iron Decide If It Is a Magnet?
Inside a piece of iron are tiny neighborhoods called domains. Each domain holds millions of atoms that all point their magnetic directions the same way. Whether the iron is a magnet depends on how these neighborhoods point!
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Why Do Some Magnets Lose Their Power Over Time?
Magnets do not last forever. A magnet gets weaker when the domains inside it get scrambled. Many fridge magnets last for years. But a dropped or heated one can weaken fast.
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What Is the Difference Between a Permanent Magnet and a Temporary Magnet?
A permanent magnet keeps its magnetism for a long time. A temporary magnet acts like a magnet only while another magnet is nearby. Let's meet them both!
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How Do Scientists Measure How Strong a Magnet Is?
Scientists have special tools that measure how strong a magnetic field is. They read the strength in units called gauss or tesla. You can compare magnets at home too, using nothing fancier than paper clips!
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Why Do Two Magnets Seem to Jump Together at the Last Moment?
Have you ever felt two magnets jump together at the last moment? A magnet's pull grows stronger very quickly as the magnets get closer.
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Why Does One Magnet Seem to Float Above Another?
When you stack ring magnets with matching poles facing, the top one seems to float! The magnets push each other apart, and that push holds the top one up.
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Can a Magnet Have Only One Pole?
So far, no one has ever found a magnet with just one pole. Every magnet ever made or found has both a north and a south pole. A single magnetic pole is called a monopole.
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How Did the Poles of a Magnet Get the Names North and South?
The names north pole and south pole come from how a magnet points on Earth. Long ago, people noticed something about a magnet that could swing freely. Their clue turned into the names we still use today.
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How Is Magnetic Force Different From Gravity?
Magnetic force and gravity are both invisible forces, but they act in different ways. Gravity only pulls, while magnetism can pull or push. Gravity keeps your feet on the ground, and a fridge magnet holds up your drawings.
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Why Does the Pull of a Magnet Get Stronger When It Is Closer?
A magnet pulls harder when it is closer for the same reason a flashlight looks brighter up close. Magnetic fields spread out in all directions as they leave the poles.
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Is Magnetism the Same as Electricity?
Magnetism and electricity are two sides of one force, called electromagnetism. They are closely connected, but they are not the same thing. A fridge magnet, for example, needs no wires or batteries at all.
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What Are the Strongest Magnets in the World?
Some magnets are small enough to fit in your hand, and some are as big as a room. The strongest everyday magnets are made of neodymium, iron, and boron. Let's climb a ladder of magnet strength, from gentle to giant!
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Why Do Two Magnets Pushing Apart Feel Like Pressing on a Springy Cushion?
Push two magnets together with matching poles facing, and something strange happens. It feels like you are pressing on a springy cushion, even though nothing is touching!
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How Do Factories Make Magnets?
Magnets are made in factories, and the recipe starts with metal. Workers pour, press, and shape the metal into the form they want. Then comes the most important step.
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What Happens When You Bring a Magnet Near a Compass?
A compass needle is a small magnet that can spin freely. It points along the strongest magnetic field nearby. A compass needle is a tiny magnet.
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Is All Stainless Steel Magnetic?
Is stainless steel always magnetic? No! Stainless steel is iron mixed with chromium and sometimes nickel. Recyclers use magnets to help sort different types of steel.
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Why Do Magnets Stick to Some Coins but Not Others?
Take a magnet and test a handful of coins, and you may get a surprise. Some coins stick, some do not, and some stick just a little. The secret is in what the coin is made of.
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What Is Lodestone, the Natural Magnet?
Long ago, people found strange rocks in the ground that could attract iron. We call them lodestones, and they are natural magnets.
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Why Won’t Magnets Stick to Wood, Glass, or Plastic?
Magnets are picky. They stick to only a few kinds of materials. Wood, glass, and plastic are not on the list. Only iron, nickel, and cobalt respond strongly.
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Why Do Magnets Cling to Steel Doors but Not to Walls?
Magnets love to cling to a steel fridge door, but they will not cling to a wall. A fridge door usually has a thin steel layer hiding under its paint or plastic.
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How Can a Magnet Tell a Steel Can From an Aluminum Can?
A magnet can sort cans without even looking at them. Food cans are usually steel, and many soda cans are aluminum. A magnet can lift tons of steel at a recycling plant.
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Why Can a Magnet Pull Black Grains Out of Beach Sand?
Walk along some beaches and you might spot dark streaks in the sand. Those streaks hide tiny black grains that a magnet can pull right out.
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Is There Really Iron in Breakfast Cereal?
Many breakfast cereals are fortified, which means iron was added to them. The iron helps people stay healthy, and it is mixed in as a fine metal powder.
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Is Rust Magnetic?
Is rust magnetic? Ordinary rust is a reddish iron oxide, and it is only very weakly magnetic. A magnet can still stick to a rusty nail, though.
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What Is Ferrofluid, the Liquid That Grows Spikes?
Ferrofluid is a strange liquid that grows spikes when a magnet comes near. It is full of magnetic particles so tiny that they float like dust in sunlight.
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Why Does a Magnet Stop Working When It Gets Very Hot?
Heat can make a strong magnet stop working. When atoms get hot, they jiggle faster and faster. This one is for learning about only, never for trying at home!
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Can Anything Block a Magnetic Field?
Is there any way to block a magnetic field? Nothing blocks it completely, but some materials can redirect it. Engineers use that trick to protect delicate equipment, like very sensitive science instruments.
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Why Do Flexible Fridge Magnets Have Stripes?
Flexible fridge magnets have a secret hidden inside them. They are made of rubber mixed with magnetic powder, and they are magnetized in thin stripes.
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Is Everything a Little Bit Magnetic?
Is everything a little bit magnetic? In a way, yes! Everything reacts to a very strong magnetic field, even a pencil, a banana, or you, just a tiny bit.
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How Do Click-Together Magnetic Building Tiles Work?
Click-together magnetic tiles snap into shapes and come apart with a flip. Hidden inside each tile are small magnets, set in a pattern.
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How Do Magnetic Drawing Boards Work?
A magnetic drawing board lets you draw a picture and erase it with one swipe. It looks like magic, but it is really a clever trick with magnets and tiny cells of powder.
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How Does Magnetic Putty Swallow a Magnet?
Magnetic putty seems to gobble up a magnet, like a very slow monster. It is a stretchy putty that is mixed with fine iron powder. Magnetic putty flows like a very thick liquid.
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How Can You Find the Poles of a Magnet That Has No Label?
Imagine you find a magnet with no label at all, and you need to know which end is north. A compass can solve the mystery. A compass is a handy pole detector.
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Why Does a Magnet Stick Harder to Thick Steel than to Thin Steel?
A magnet sticks harder to a thick piece of steel than to a thin one. It all comes down to how much magnetic field the steel can carry.
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How Can a Magnet Make a Paper Clip Hover in the Air?
Can a paper clip hover in the air, held up by an invisible pull? Yes, with a thread, a magnet, and a little patience. The magnet's field passes through the air and the card.
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Can Magnets Help Find Rocks That Fell From Space?
Some rocks fall from space, and they are called meteorites. Many of them contain iron and nickel, which means a magnet may help find them. Let's go on a meteorite hunt, and find out how a magnet can help.
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How Does a Magnet Sweeper Pick Up Scattered Nails?
Imagine a workshop floor covered in sharp nails, tacks, and screws. A magnet sweeper can clean it up, with no pricked fingers at all.
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Why Do Some Fridge Magnets Slide Down the Door?
Have you ever seen a fridge magnet slowly slide down the door? A fridge magnet pulls straight into the door, but gravity pulls it straight down.
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Why Do Magnets Ignore Real Gold and Silver?
Gold and silver are beautiful, but magnets just ignore them. These shiny metals are not magnetic at all. Pure iron is much more magnetic than any common jewelry metal.
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How Can You Sort a Mystery Pile of Objects with Only a Magnet?
You have a mystery pile of small objects, and only a magnet to sort them. A magnet is a great tool for splitting any pile into two groups.
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Why Is Earth Like a Giant Bar Magnet?
Earth has a magnetic field that looks a lot like the field around a giant bar magnet. It has a north end and a south end, and it reaches every place on the planet. But there is no giant magnet hiding inside!
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How Does Swirling Liquid Metal Deep Inside Earth Make a Magnet?
Deep under your feet, a layer of melted metal swirls around and around. That swirling is what makes Earth's magnetic field. The outer core is about 1,400 miles thick.
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Why Does Earth’s Inner Core Stay Solid Even Though It Is So Hot?
At the very center of Earth sits a ball of iron and nickel as hot as the surface of the Sun. Even so, it is solid! The inner core is a little smaller than the Moon.
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What Does the Magnetic Shield Around Our Planet Do?
Our planet has an invisible shield wrapped all around it. It is Earth's magnetic field, and it protects us from a stream of particles flying out from the Sun.
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What Happens When the Solar Wind Hits Earth’s Magnetic Shield?
The Sun is always blowing a wind of tiny charged particles out into space. It is called the solar wind, and it blasts past Earth all the time.
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What Is the Magnetosphere?
Earth's magnetic field does more than point your compass north. It builds a huge bubble in space, and our planet sits right in the middle.
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Why Is Earth’s Magnetic Bubble Shaped Like a Comet?
Earth's magnetic bubble is not round like a ball. It is squeezed on one side and stretched on the other, a bit like a comet. The night-side tail can reach hundreds of thousands of miles.
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Why Do Magnetic North and True North Point Different Ways?
A compass needle does not point exactly to the North Pole. It points toward a different spot, called magnetic north. Maps for hikers often show the local declination.
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Is the Magnetic North Pole Really Moving?
Earth's magnetic north pole is not staying still. It wanders across the Arctic year after year. The pole moved fastest in the early 2000s.
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Which Scientists Track the Pole as It Travels?
Because the magnetic poles keep moving, someone has to keep track of them. Teams of scientists around the world do exactly that. Let's meet these pole trackers, who work on the ground, in the sky, and even in space!
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Did the North and South Magnetic Poles Ever Swap Places?
Here is a surprising fact: Earth's north and south magnetic poles have swapped places before! Rocks tell us it has happened hundreds of times in the past, though at irregular times.
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How Do Cooled Lava Rocks Keep a Record of the Old Field?
Rocks can remember! When lava cools, tiny magnetic grains in it line up with Earth's field at that moment. These rocks are nicknamed fossil compasses.
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What Tools Measure the Pull of Earth’s Magnet?
How do scientists measure the pull of Earth's magnet? They use special sensors called magnetometers. You even have one in your pocket, if you own a phone!
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Why Is There a Weak Spot Over the South Atlantic Ocean?
Earth's magnetic field is strong in some places and weak in others. Over South America and the South Atlantic Ocean, it is weaker than almost anywhere else.
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What Would Life Be Like If Earth’s Shield Vanished?
Imagine waking up one morning, and Earth's magnetic shield was gone. What would happen to life on Earth? Let's think it through, step by step, like real scientists do.
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Why Did Mars Lose Its Magnetic Field?
Mars once had a magnetic field, a bit like Earth's. Today it is gone. Old magnetism is still locked in some Mars rocks. Mars is small, so it cooled faster than Earth.
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Do Other Planets Have Magnetic Fields?
Does Earth have the only magnetic field in space? Not at all! Many planets have magnetic fields, and some are very strange. Ganymede, a moon of Jupiter, has its own magnetic field.
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Why Does Jupiter Have Such a Huge Magnetic Field?
Jupiter has the most powerful magnetic field of any planet. Its magnetic bubble is so huge that, if we could see it from Earth, it would look bigger than the full Moon!
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Why Do Scientists Call the Sun a Giant Magnet?
We usually think of the Sun as a ball of fire and light. Scientists also call it a giant magnet! And remember, never look at the Sun directly, because it can hurt your eyes.
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What Are Sunspots, and What Do Magnets Have to Do with Them?
Some days, the Sun has dark patches on its surface called sunspots. They look like tiny freckles, but some are bigger than Earth! Some sunspots are larger than Earth.
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Why Do Compass Needles Wiggle During a Magnetic Storm?
Sometimes the Sun throws out a giant burst of charged particles. When they hit Earth's magnetic field, they shake it, and that can make a compass needle wiggle.
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Is Earth’s Magnet Stronger than a Fridge Magnet?
Which is stronger, the magnet in your hand or the magnet under your feet? The answer is a surprise. Earth's field is much weaker than a fridge magnet's, but it is also much, much bigger!
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Could Astronauts Use a Compass on the Moon?
Imagine walking on the Moon with a compass in your hand. Which way would the needle point? The answer might surprise you! Spacecraft found weak patches of magnetism on the Moon's surface.
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Why Does a Hanging Magnet Tilt Downward Near the Poles?
Earth's magnetic field lines do not just run across the ground. Near the poles, they dive straight down into the planet! Compass makers build different compasses for different parts of the world.
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Is Earth’s Magnetism the Same Strength Everywhere?
Earth's magnetic field is not the same strength everywhere you go. It is stronger in some places and weaker in others. Northern Canada's field is much stronger than the equator's.
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How Did People First Discover the Compass?
The compass is one of the greatest tools ever invented. But nobody knows the exact day it was discovered. Here is the story of how people probably found it.
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What Do the Letters and Numbers on a Compass Mean?
A compass is covered with letters and numbers. They are not decorations, they are a secret code for finding your way. Let's crack the code and learn to read the dial like a real explorer!
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Why Is the Needle in Many Compasses Floating in Liquid?
Look closely at many compasses, and you will see something strange. The needle floats in a clear liquid! The liquid inside a compass is usually a clear oil or alcohol.
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How Can You Walk in a Straight Line Using a Compass?
Have you ever tried to walk in a straight line without a path? It is much harder than you think! A compass can help you stay on track.
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What Can Fool a Compass?
A compass seems simple, but lots of things can fool it. Anything magnetic, or any electric current nearby, can pull on a compass needle.
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How Can You Build a Simple Compass at Home?
You can build your very own compass at home with just a few simple things. All you need is a steel pin or paper clip, a magnet, and a bowl of water. Let's build one together, with a grown-up to help!
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Do Compasses Work the Same in the Southern Hemisphere?
Does a compass work the same way in the Southern Hemisphere? Yes, it still points toward magnetic north! But there is a tricky detail that compass makers have to think about.
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How Did Sailors Steer Before GPS?
Long ago, sailors crossed whole oceans without GPS. They did it by combining many simple tools, and a lot of careful thinking. There were no satellites, no screens, and no maps on a phone.
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Why Do Iron Ships Need Compass Corrections?
Big iron and steel ships have a problem with compasses. The ship itself becomes a little magnetic, and that fools the needle! A compass can get confused by the very ship it is sitting on.
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How Does a Gyrocompass Find North Without a Magnet?
Is there a compass that works without any magnet at all? Yes! It is called a gyrocompass. A spinning bicycle wheel is also hard to tilt, for the same reason.
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Why Do We Still Need Compasses When We Have GPS?
GPS is amazing, but it does not always work. So smart hikers still carry a compass. A compass can still work when a phone battery is dead.
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What Is Orienteering?
Imagine a race where your map and compass matter as much as your legs. That is orienteering! Orienteering courses come in many levels, from easy beginner paths to expert ones.
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Why Does a Phone Ask You to Draw a Figure Eight to Fix Its Compass?
Sometimes a phone asks you to wave it in a figure eight to fix its compass. It might seem like a silly dance. But it is really clever science, and here is why.
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Can a Compass Work Underwater?
Can a compass really work underwater? It sounds tricky, because water changes so many things. But magnets and water get along just fine!
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What Is a Compass Rose on a Map?
Look at a map, and you may see a pretty little star or flower in one corner. That is a compass rose! The points look like petals, which gives the rose its name.
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How Do Pilots Use Compass Headings, and Why Do Runways Have Numbers?
When pilots fly, they need to know exactly which way to go. They use compass headings, and airports even put those numbers on the runways!
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How Do People Find Their Way in the Arctic When Compasses Wobble?
The Arctic is a land of ice and snow, and it is also close to the magnetic north pole. That makes a regular compass act strangely.
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Does Moss Really Grow Only on the North Side of Trees?
You might have heard that moss grows only on the north side of trees. Is it true? Let's put on our science hats and find out, and see what a real explorer should trust.
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How Did Pacific Wayfinders Cross Oceans Without a Compass?
Thousands of years ago, brave sailors crossed huge oceans in canoes. They had no compasses, and no maps, and yet they found tiny islands in the Pacific.
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Why Do Most Maps Put North at the Top?
Look at almost any map, and north is at the top. But there is no law of nature that says it has to be! The word orient comes from the old habit of putting east at the top.
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What Should You Do If You Get Lost on a Trail?
Getting lost on a trail can feel scary. But if you know the right steps, you can stay safe. Let's learn what to do, and then practice with a grown-up.
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How Can a Watch and the Sun Show You Which Way Is South?
Here is a cool trick for finding south with nothing but a watch and the Sun. It works in the Northern Hemisphere with an old-style watch that has hands. Let's learn how.
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What Is Dead Reckoning?
Imagine you are lost at sea, with no GPS and no landmarks anywhere. How could you figure out where you are? Navigators use a clever method called dead reckoning.
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How Do Geocachers Use Coordinates to Find Hidden Treasure?
Imagine a treasure hunt where the treasure is hidden somewhere in the real world. It is called geocaching, and people play it all over the globe.
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How Can Sunrise and Sunset Help You Find Directions?
The Sun can be a natural compass. It rises in one place and sets in another. In summer in Canada, the Sun rises well north of east.
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How Does a Fridge Door Stay Sealed Without a Latch?
Have you ever noticed that a fridge door closes tight without any latch or lock? The secret is a magnet hidden in the rubber seal around the edge.
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How Do Cabinet Doors Click Shut with Magnets?
Push a cabinet door almost closed, and it clicks shut all by itself. There is no spring, no hook, and no latch. Just a small magnet and a bit of steel working together!
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How Does an Electromagnet Switch on and Off?
Imagine a magnet you can switch on and off, like a light. It is called an electromagnet! An electromagnet is often strong enough to lift a car when it is built large enough.
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How Does a Giant Magnet Lift Cars and Scrap Steel?
At a scrap yard, a giant crane lifts a huge pile of steel with no hooks or ropes around it. It uses a giant electromagnet instead. Nothing is tied on, and nothing is hooked.
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How Do Magnets Help an Electric Motor Spin?
Inside a fan, a toy car, or even your phone, a small motor is spinning. And magnets are the secret to how it works. A tiny motor in a phone makes it buzz.
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How Can Spinning a Magnet Make Electricity?
A spinning magnet can make electricity! That is how most of the power that lights your home gets made. A bicycle light often uses a small generator called a dynamo.
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Why Must Metal Stay Out of the Room with an Mri Machine?
In a hospital, there is a room with a very special rule: no metal allowed! It holds an MRI machine, with one of the strongest magnets people have ever used in a hospital.
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How Do the Stripes on Some Cards Store Information?
Turn over a gift card or a hotel key card, and you might see a dark stripe. It looks like plain brown tape, but it hides a secret code made from tiny magnets.
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How Do Tapes and Hard Drives Store Information with Magnets?
Old cassette tapes and computer hard drives look very different. But they share a secret: both store information using tiny magnetic patterns. One saves music, and the other saves almost everything on a computer.
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How Does a Magnet Help a Window Alarm Know When It Opens?
A window alarm can tell the moment a window opens, even though it has no eyes. The secret is a magnet and a tiny glass switch. Doors use the same trick. A reed switch has no moving parts you can see.
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How Does a Bike Computer Count Wheel Turns?
A bike computer can tell you how fast you are going and how far you have ridden. But it never touches the wheel! The trick is a tiny magnet and a sensor that notice each turn.
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How Can a Train Float on Magnets?
Imagine a train that floats just above its track, with no wheels touching at all. It is called a maglev train, and it really exists!
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How Can Magnets Slow Down a Roller Coaster Without Touching It?
At the end of some roller coasters, the cars slow to a smooth stop without anything touching them. The secret is magnets! The faster the coaster goes, the stronger this magnetic braking is.
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Why Does a Magnet Fall Slowly Through a Copper Pipe?
Drop a magnet through a plastic pipe, and it falls fast. Drop it through a copper pipe, and it falls slowly, as if something invisible is catching it!
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How Can a Cooktop Heat a Pot Without a Flame?
Some stoves can cook your dinner without a single flame. They use an invisible magnetic field to heat the pot. A grown-up should always do the cooking!
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How Can a Fire Door Stay Open and Still Close by Itself?
In some school hallways, heavy fire doors stay wide open all day. But when there is a fire alarm, they swing closed all by themselves!
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How Can a Lamp or Globe Float Above Its Base?
In some shops and homes, a lamp or a globe floats in the air above its base. It seems like magic, but it is really clever engineering.
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How Do Metal Detectors Find Hidden Metal?
Metal detectors can find coins, keys, and treasure hidden under sand or soil. They work with an invisible magnetic field. Some detectors can tell different metals apart by how they respond.
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How Does a Laptop Know When Its Lid Closes?
Close your laptop, and the screen turns off at once. Open it, and the laptop wakes up. There is no button to push, so how does it know?
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Why Is Some Money Printed with Magnetic Ink?
Some paper money and bank checks have a secret ingredient in their ink: tiny magnetic particles! You cannot see the magnetism, but machines can sense it.
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How Do Pinball Flippers Flick the Ball?
Press the button on a pinball machine, and the flipper snaps up in a flash. Inside, an electromagnet is hard at work, even though you cannot see it.
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How Does an Electric Guitar Turn Plucked Strings Into Sound?
An electric guitar does not have a big hollow body to make its sound louder. Instead, it has magnets and thin wire hiding under the strings.
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Why Can a Spinning Top Float Above a Magnetic Base?
Some toys have a spinning top that floats in the air above a magnetic base. It seems to defy gravity! It looks like a magic trick, but it is real science.
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How Do Food Factories Catch Stray Bits of Metal?
Food factories work hard to keep every bite safe. Sometimes a tiny bit of metal, like a screw end or a wire piece, breaks off a machine. Magnets help to catch those stray bits!
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How Do Toy Train Cars Link Up with Magnets?
Wooden toy trains can link together without any hooks or buckles. The secret is hidden magnets in the ends of each car. Hidden magnets in toys must be sealed in tightly so little ones cannot swallow them.
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How Do Sea Turtles Use Earth’s Magnet to Find Their Way?
A baby sea turtle hatches on a beach, swims out to sea, and years later returns to lay its eggs on the very same beach. How does it find its way across a huge ocean? It may use Earth's magnetic field as a map!
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Do Birds Really Have a Built-In Compass?
Every year, many birds fly thousands of miles to warmer places and then back again. They do not use maps or GPS. Do birds really have a built-in compass?
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Can Sharks Use a Magnetic Map to Swim Home?
Sharks swim across huge oceans and somehow find their way home. Scientists wondered if they might use a magnetic map. Here is how they tested some small sharks to find out!
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How Might Salmon Use Earth’s Magnet to Return to Their Home River?
Salmon begin their lives in a small river. They swim out to the ocean for years, and then return to the very same river where they were born. How do they find it?
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Do Cows and Deer Really Face North and South?
In 2008, some scientists made a surprising claim. They said cows and deer might line up north and south when they graze or rest. Scientists use the word replicate for repeating an experiment.
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Which Tiny Living Things Carry Their Own Compass Needles?
Some of the tiniest living things on Earth carry their own compass needles. They are so small that you need a powerful microscope to see them. Let's meet these magnetic bacteria!
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How Do Spiny Lobsters Use a Magnetic Map?
Spiny lobsters can crawl a long way across the ocean floor and still find their way home. They do not have eyes that work in the dark depths. Scientists wondered if they use a magnetic map.
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How Do Monarch Butterflies Use a Magnetic Compass?
Every fall, monarch butterflies fly thousands of miles to Mexico. Even though they are tiny, they find their way to the very same forests.
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Why Don’t Our Bodies Sense Magnets the Way They Sense Heat?
Birds, turtles, and sharks seem to sense magnets. But can you feel a magnet from far away? Humans cannot, and scientists are curious about why.
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How Do Mole-Rats Use Magnetism Underground?
Deep underground, there are animals that live in total darkness. Ansell's mole-rats in Africa live in dark tunnels and have very poor eyesight. How do they know which way to go?
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How Do Scientists Test Whether an Animal Can Sense Magnetism?
How can a scientist find out whether an animal can sense magnetism? The animal cannot tell us, so scientists must be clever. Scientists must keep the experiment free of metal that could change the field.
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Could Bees or Ants Use Magnetism to Find Their Way?
Honeybees and ants are tiny, but they are great at finding their way home. Could magnetism be part of their secret? Bees can also sense the polarized pattern of light in the sky.
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What Is a Magnetar?
Far out in space, there is a star with the strongest magnetic field anyone has ever found. It is called a magnetar. Magnetars sometimes release huge bursts of energy that astronomers can detect from thousands of light-years away.
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Why Do Mars Rovers Carry Magnets?
Robots on Mars have carried small magnets, and it was not to stick things on a fridge. They used the magnets to catch dust from the air.
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Do Magnets Work on the Space Station?
Do magnets still work when you float far above the ground in space? Yes, they do! There is even a giant magnet on the International Space Station.
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How Do Satellites Use Magnets to Turn Without Fuel?
How do you turn a satellite in space, where there is nothing to push against? One answer is magnets! It sounds like a trick, but engineers really use it.
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Do Auroras Glow on Jupiter and Saturn Too?
You may have heard of the auroras on Earth, the colorful northern and southern lights. But they are not only on Earth! Let's visit other planets to see their glowing skies, and find out what makes them shine.
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Why Are Small Magnets Dangerous If Swallowed?
Small magnets are fun to play with, but they have a dangerous side. If you swallow them, they can hurt you. This is one of the most important safety lessons of all, so let's listen carefully.
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Why Should You Keep Strong Magnets Away From Phones and Bank Cards?
Strong magnets are amazing, but they do not belong next to your favorite gadgets. A magnet can scramble a bank card or confuse a phone.
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Why Can Strong Magnets Pinch Fingers and Shatter?
Super-strong neodymium magnets are not toys. They can pinch a finger badly, and they can even shatter like glass. Let's learn why, and how to stay safe.
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Why Must Some People Stay Away From Strong Magnets?
Some people have special medical devices inside their bodies that help them stay healthy. Strong magnets can affect those devices.
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How Should You Store Magnets?
You have learned lots of cool things about magnets. Now here is how to take care of them. Storing magnets the right way keeps them strong, and keeps everyone safe.
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How Can You Tell If a Magnet Toy Is a Safe Choice?
Magnet toys can be great fun, but not every magnet toy is right for every age. How can you tell if one is a safe choice? Let's learn the checklist that grown-ups use!
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