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Magnets An object that attracts things made of iron is a magnet. Magnets attract, or pull, other objects. What kinds of objects do you think magnets attract? You can do tests to find out. Get a magnet and see what objects get pulled to the magnet. 2 horseshoe magnet
These magnets in the letters pull to the steel in the refrigerator. Not all things made of metal are attracted to magnets. Magnets attract things that have iron in them. Steel has iron in it. Magnets can attract steel things. Think about objects in your home. What do you have at home that a magnet might attract? MAIN IDEA AND DETAILS What does a magnet attract? 3
What Can Magnets Attract? Magnets attract steel paper clips. Magnets also attract other magnets. Think about objects in your classroom. Do you see anything that a magnet could attract? Some magnets are stronger than others. A strong magnet can attract many paper clips at once. A weak magnet can only attract a few paper clips. 4
What will the magnet attract? What will the magnet not attract? There are many things that a magnet does not attract. A magnet does not attract paper, wood, or plastic. Why are these things not attracted to magnets? Can you name other things not attracted to magnets? MAIN IDEA AND DETAILS Will a magnet attract a wooden block? 5
Magnets Have Poles A magnet has two poles. A pole is near an end of a magnet. A magnet has an north pole. A magnet has an south pole, too. The N stands for north and the S stands for south. A magnet s pull is strongest at the poles. 6
These poles are not the same. They attract each other. Earth has a north pole and a south pole. Poles attract other poles that are not the same. An N pole attracts an S pole. Poles do not attract if they are the same. Get two magnets. Do a test to find out. MAIN IDEA AND DETAILS Where is a magnet s pull strongest? 7
Why Magnets Repel A compass needle is a small magnet. It always points to Earth s North Pole. These poles are the same. They repel. Poles that are alike repel, or push away from, each other. Two N poles will repel each other. Two S poles will repel each other. You can see magnets repel. You can feel magnets repel, too. 8
Look at the two pictures. In the first picture, how can you tell the magnets are attracting? The magnets touch. In the second picture, how can you tell the magnets are repelling? The magnets push away from one another. CAUSE AND EFFECT What causes two poles to repel? 9
Magnets Have Force A magnet has force. A magnet s pull is called magnetic force. A magnet can pull a steel toy car through a sheet of paper. A strong magnet can attract objects through other things, such as cloth, water, or even your hand! Some magnets can attract objects without even touching them. The magnet on this pole pulls through air to catch the fish. 10 MAIN IDEA AND DETAILS What is magnetic force?
A magnet can pull through air to move this truck. Summary Magnets attract objects made of iron or steel. Magnets have two poles. Poles attract and repel each other. A magnet s force can pass through things like paper and water. Strong magnets can pull objects without touching them. 11
Glossary attract To pull something (2, 3, 4, 5, 7, 9, 10, 11) pole Near the ends of a magnet where the pull is strongest (6, 7, 8, 9, 10, 11) repel To push away (8, 9, 11) magnet An object that will attract things made of iron (2, 3, 4, 5, 6, 7, 8, 9, 10, 11) magnetic force A magnet s pull (10) 12
Think and Write 1. Will an N pole repel an S pole? 2. MAIN IDEA AND DETAILS What can attract things made of iron? 3. MAIN IDEA AND DETAILS Can a magnet attract paper? 4. Write about an object that uses a magnet to work. Hands-On Activity Does a magnet attract this book? Does a magnet attract a crayon? Make two groups of objects on your desk. One group attracts to a magnet. The other group does not attract to a magnet. School-Home Connection Where do you use magnets? With an adult family member, search for magnets in your home. Count your magnets. iii