5 All About Magnets

该页暂无翻译

All About Magnets BY SARAH KOVATCH

Chapter 1 All Kinds of Magnets Do you have magnets in your home? You have magnets in your telephone, in your washing machine, probably in your can opener, too. Some of your toys have magnets. You may even have magnets on your refrigerator door. They may be holding up photos of you right now! Magnets are everywhere. They can move some things without touching them. They can pick up other things. What is so special about a magnet? A magnet can attract, or pull, objects toward it.

A magnet will not attract just any object. The object it attracts must be made of special metals such as iron or steel. Magnets are also made of these metals. Any object that is able to be pulled to a magnet is magnetic. Objects made of rubber, paper, and plastic are not magnetic. Magnets cannot pull, or attract, them.

Chapter 2 Push and Pull Magnets come in all shapes and sizes. They can be in the shape of a candy bar, a horseshoe, or even a circle. Magnets can be large or small. But they all share one thing. All magnets have two poles. One end of the magnet is called the north pole. The other end is called the south pole. Suppose you put two magnets next to each other. The north pole and the south pole would attract, or pull toward each other. But two north poles or two south poles would repel, or push each other away. Remember: Opposite poles attract. Like poles repel.

Did you know that Earth is a big magnet? That is because Earth has a lot of iron in it. The iron turns slowly inside Earth. That creates a magnetic field around Earth. All magnets have a magnetic field. This is the area around a magnet where its force pulls or pushes objects. The closer the object is to the magnet, the stronger the pull or push. The farther away the object is, the weaker the pull or push.