Magnets in Everyday Use

Transcription

1 Magnets in Everyday Use

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

3 Copyright Texas Education Agency, 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: 1) Texas public school districts, charter schools, and Education Service Centers may reproduce and use copies of the Materials and Related Materials for the districts and schools educational use without obtaining permission from the Texas Education Agency; 2) Residents of the state of Texas may reproduce and use copies of the Materials and Related Materials for individual personal use only without obtaining written permission of the Texas Education Agency; 3) Any portion reproduced must be reproduced in its entirety and remain unedited, unaltered, and unchanged in any way; 4) No monetary charge can be made for the reproduced materials or any document containing them; however, a reasonable charge to cover only the cost of reproduction and distribution may be charged. Private entities or persons located in Texas that are not Texas public school districts or Texas charter schools or any entity, whether public or private, educational or non-educational, located outside the state of Texas MUST obtain written approval from the Texas Education Agency and will be required to enter into a license agreement that may involve the payment of a licensing fee or a royalty fee. For more information, contact: Office of Copyrights, Trademarks, License Agreements, and Royalties. Texas Education Agency N. Congress Ave., Austin, TX ; phone ; copyrights@tea.state.tx.us 2

4 DYK Did You Know? Did You Know? Magnets in Everyday Use 3

5 DYK Did You Know? Did you know there is a magnet in a motor? magnet magnet magnet small motor World s Simplest 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. 4

6 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. 5

7 DYK Did You Know? Did you know there are magnets in headphones and in speakers? magnet 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. 6 Never open a speaker that is connected to a power source.

8 DYK Did You Know? Did you know a generator is just a motor working backward? hand crank generator generator 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. 7

9 DYK Did You Know? 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. 8

10 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. 9

11 DYK Did You Know? Did you know an electromagnet is created when a coil of wire is wound around an iron core and electric current flows through it? electromagnet To make a job easier, large electromagnets may be used to lift heavy materials. 10

12 DYK Did You Know? Did you know magnets help make things around your house work? 11

13 DYK Did You Know? 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. 12

14 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. 13

15 Which of these magnets do you use every day? 14

16 15

17