Discover the magnets that power your world
Learning Objective: Students will use evidence from a text, a video, and a hands-on investigation to communicate information about magnets.
Here’s where you might find magnets around your home!
Here’s where you might find magnets around your home!
Illustration by Sergey Kostik (Home); Shutterstock.com (Background)
Headphones: Electric currents run through an electromagnet inside headphones. This creates vibrations that we hear as sound.
Headphones: Electric currents run through an electromagnet inside headphones. This creates vibrations that we hear as sound.
Computer: Hard drives use magnets to store information. That’s why strong magnets can erase a computer’s memory.
Computer: Hard drives use magnets to store information. That’s why strong magnets can erase a computer’s memory.
Mixer: Magnets power the motors that make electric mixers spin.
Mixer: Magnets power the motors that make electric mixers spin.
Television: Many TVs contain magnets that direct the flow of energy through the screen.
Television: Many TVs contain magnets that direct the flow of energy through the screen.
Doorbell: Pushing a doorbell connects a small electric circuit. The circuit turns on an electromagnet that dings a bell.
Doorbell: Pushing a doorbell connects a small electric circuit. The circuit turns on an electromagnet that dings a bell.
Toys: The powers of attraction that magnets have make many toys work, like trains, magnetic blocks, and writing boards.
Toys: The powers of attraction that magnets have make many toys work, like trains, magnetic blocks, and writing boards.
Car: Cars contain magnets in brake systems, seat belts, and doors. (And in electric cars, magnets help power the motors!)
Car: Cars contain magnets in brake systems, seat belts, and doors. (And in electric cars, magnets help power the motors!)
Electric Toothbrush: Magnets help electric motors move, powering your electric toothbrush and other devices!
Electric Toothbrush: Magnets help electric motors move, powering your electric toothbrush and other devices!
You may have used a magnet to stick a drawing to your refrigerator. But did you know that magnets are found in toys, computers, and dozens of other objects in your home too?
“Magnetism is everywhere!” says Carlos Villa. He works at the National High Magnetic Field Laboratory (MagLab) in Tallahassee, Florida. The facility is home to thousands of strong magnets. Its largest magnet weighs 35 tons. It’s 1,500 times stronger than the magnets on your refrigerator!
Experts at MagLab teach the public about magnets. Scientists also travel there to use magnets in experiments. What they learn can reveal the properties of different materials and lead to life-changing technologies.
You may have used a magnet to stick a drawing to your refrigerator. But did you know that there are other magnets in your home? They can be found in toys, computers, and dozens of other objects.
“Magnetism is everywhere!” says Carlos Villa. He works at the National High Magnetic Field Laboratory (MagLab). It’s in Tallahassee, Florida. The lab is home to thousands of strong magnets. Its largest magnet weighs 35 tons. It’s 1,500 times stronger than the magnets on your fridge!
Experts at MagLab teach people about magnets. Scientists also travel there to use magnets. Their tests can show the properties of different materials. And they can lead to new technologies.
Opposites Attract
How do magnets work? A magnet is surrounded by an area called a magnetic field. In this space, a magnet exerts an invisible force called magnetism. That force allows magnets to push or pull certain objects without touching them.
Magnets can attract or repel materials that have magnetic properties—such as the metals iron, nickel, and cobalt. Most magnets don’t affect materials with weak magnetic properties, like plastic, wood, and cotton.
Materials with magnetic properties can be magnetized, or made into a magnet. Some types of magnets, called permanent magnets, stay magnetized forever. Other objects have a magnetic field only when electricity flows through them. These magnets are called electromagnets.
All magnets have a north pole and a south pole. Opposite poles attract each other, while similar poles push each other away. You may have felt this push or pull if you’ve ever held two magnets together!
How do magnets work? A magnet is surrounded by a magnetic field. This area contains an invisible force a magnet gives off. This force is called magnetism. It allows magnets to push or pull certain objects. And that’s without touching them.
Magnets can attract or repel certain materials. They have magnetic properties. These materials include the metals iron, nickel, and cobalt. Most magnets don’t affect materials like plastic, wood, and cotton.
Materials with magnetic properties can be magnetized. That means they can be made into a magnet. Some types of magnets are permanent. They stay magnetized forever. Other objects only have a magnetic field sometimes. That’s when electricity flows through them. They are called electromagnets.
All magnets have a north pole and a south pole. Opposite poles attract each other. Similar poles push each other away. Hold two magnets together. You’ll feel this push or pull!
iStockPhoto/Getty Images
At junkyards, powerful magnets are used to move and sort metal scraps.
Magnets Everywhere!
Thanks to magnets’ special properties, people use them for all kinds of things. Small magnets keep the doors of refrigerators closed. At wrecking yards, large magnets are used to lift whole cars. Some types of trains contain magnets under the cars and in the tracks. These magnets repel one another, causing the train cars to float.
Magnets also power motors in electric devices, like blenders and ceiling fans. Connecting these devices to electricity turns on electromagnets in the motor. These magnets attract and repel other magnets, causing the motor to spin.
Magnets are also used to create images. A magnet-powered device called an MRI machine lets doctors look inside patients’ bodies. The machine creates images based on how cells are affected by the machine’s strong magnetic field.
At MagLab, scientists use superstrong magnets to create images of the insides of all kinds of objects. “The stronger the magnet, the better the imaging system is,” says Villa. Magnets have revealed the makeup of batteries, algae, and even dinosaur fossils!
People use magnets for all kinds of things. That’s all thanks to magnets’ special properties. Small magnets keep the doors of refrigerators closed. Large magnets at wrecking yards lift whole cars. Some types of trains contain magnets. They’re found under the cars and in the tracks. These magnets repel one another. That causes the train cars to float.
Magnets also power motors in devices, like blenders and ceiling fans. Connecting these devices to electricity turns on electromagnets in the motor. These magnets attract and repel other magnets. That causes the motor to spin.
Magnets are also used to create images. Magnets power a device called an MRI machine. It lets doctors look inside patients’ bodies. The machine creates images based on how its strong magnetic field affects cells.
MagLab scientists use superstrong magnets. They create images of the insides of all kinds of objects. “The stronger the magnet, the better the imaging system is,” says Villa. Magnets have shown the makeup of batteries, microbes, and even dinosaur fossils!
Stephen Bilenky/National High Magnetic Field Laboratory/Florida State University
A researcher uses a magnet-powered machine at MagLab to study the chemicals in different materials.
1. ENGAGE: Activate prior knowledge about magnets.
2. EXPLORE: Read and analyze an article about magnets.
3. EXPLAIN: Test magnetic fields and design a follow-up experiment.
4. EXTEND: Investigate how magnetic fields can attract objects from a distance.
5. EVALUATE: Synthesize new knowledge to agree upon important information about magnets.
