Did You Know?

Magnets in

Everyday Use

Magnets in Everyday Use

This book was developed in collaboration with Region 4 Education Service Center, Houston, Texas.

Copyright © Texas Education Agency, 2012. The following materials are copyrighted © and trademarked ™ as the property of the Texas Education Agency and may not be reproduced without the express written permission of the Texas Education Agency, except under the following conditions:

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Did You Know?

Magnets in Everyday Use

DYK ^{Know? Did You}

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DYK

Did you know there is a magnet in a motor?

The electricity coming into the motor causes

the pair of magnets to push and pull on the coil of wires. The coil of wires spins, turning the

motor’s shaft. That spinning can make all kinds of things move, like wheels in a motorized toy car.

small motor World’s Simplest Motor™

magnet

magnet magnet

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Larger motors have bigger magnets that move things like gears.

It is not OK to take apart objects like motors, headphones, and speakers on your own. These devices use electricity

and could shock you. You cannot see electricity, so you do not want to play with objects that might hurt you.

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DYK

Did you know there are magnets in headphones and in speakers?

headphones headphones with

earphone speaker unassembled

The wires of the headphones carry a signal to the earphone, making the magnet push and pull on a coil of wires, which moves the diaphragm of the earphones. The vibrations create the

sound you hear.

Never open a speaker that is connected to a power source.

magnet

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DYK

Did you know a generator is just a motor working backward?

A force spins the shaft, which turns the coil of wire inside the motor, generating electricity.

There are huge magnets in the generators that make the electricity that powers our school and your home.

hand crank generator generator

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DYK

Did you know there is a train that moves without wheels by using

magnetism?

What sounds like “magnet” in the name “maglev”?

mag = magnetism lev = levitate

A maglev train uses magnetism to levitate the train and push it along the track. Since the train levitates above the track, it does not experience wear and tear from wheels rolling on the tracks.

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Maglev trains are the fastest train of any type. The fastest maglev train, as of 2012, was a superconducting maglev in Japan, which could travel up to 361 mph. Right now there are no maglev trains in the United States, but there are several projects being planned.

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DYK

Did you know an electromagnet is created when a coil of wire is wound around an iron core and electric current flows through it?

To make a job easier, large electromagnets may be used to lift heavy materials.

electromagnet

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DYK

Did you know magnets help

make things around your house work?

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DYK

Did you know there are many everyday uses of magnets?

You can find a magnetic strip along the door of a refrigerator to help it seal tightly and stay shut.

You can find a magnet on an electric can opener. The magnet holds the lids of cans as they are opened.

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You can find a magnetic strip on the back of

many debit and credit

cards. There is important information stored in the strip.

The needle of a

compass is a magnet.

The needle points to Earth’s magnetic north pole.

A compass is a tool to use if you have lost your way.

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Which of these magnets do you use every day?

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Magnets in

Everyday Use