Magnetic Attraction Magnets – Activity 1 Lesson Focus Outcomes Energy and Change 2.6 Describes observable changes that occur in two objects that interact, identifying the energy source and the receiver. Indicators • Predicts which objects will be attracted by a magnet. • Classifies materials into magnetic and non-magnetic categories. • Collects and interprets data and draws simple conclusions from results. Skills Focus • Records • Observes • Identifies patterns • Conducts simple tests • Draws conclusions Background Information All magnets have a force concentrated at their two poles (north and south). All magnets have the ability to attract or repel certain objects. This ability is produced by the arrangement of electrons within the magnetic material. Electrons are extremely small particles that are found in atoms. Atoms are small particles that make up matter. Each electron has its own two poles. In most materials the electrons are randomly placed, so there is no obvious magnetic effect. However, if the electrons are lined up with their poles aligned in the same direction, then we do get a magnetic effect. Objects that do show this effect are magnets, while items attracted to a magnet are called magnetic materials. All magnetic materials are metal. However, not all metals are magnetic. Iron, nickel, cobalt and mixtures of these metals can be magnetic. So can alloys of aluminium, copper, nickel, iron and cobalt. An alloy is a metal made up of two or more metals. Iron is by far the strongest. Aluminium and some stainless steels, however, are not at all magnetic. Before the Lesson Materials Needed Magnets (different sizes and shapes; e.g. bar, horseshoe), variety of materials to test (e.g. bottle caps, cloth, aluminium cans, bolts, nuts, safety pins, cotton wool, thumb tacks, crayons, chalk, aluminium foil, coins). Preparation Magnetism activities can be set up in class stations for small groups to rotate through if material supplies are limited. The Lesson Stimulus Ask the students if they have magnets or objects that are magnetic at home. Discuss their responses. Show a variety of different types of magnets (horseshoe, bar, button, door-latch magnet, ring etc.). To introduce the idea of ‘magnetic poles’, use bar magnets with clearly labelled ends. Have children demonstrate reactions when like and unlike poles are put together. What can they ‘feel’ when the poles ‘repel’? What to Do • Have the students explore the properties of magnetic poles and record results. (Rule of Magnetism: Like poles repel and unlike poles attract.) • Within their group, have the students explore the properties of a magnet by testing a variety of the materials provided. • Group and record the materials using whether they are attracted or not attracted to a magnet as criterion. Students should be able to identify materials that attract. Materials like aluminium cans, paper, plastic, wood or corks are not attracted or repelled by magnets. • Study the objects in each group, recording any similarities (e.g. metals – attract). How are the objects the same or different from other objects or groups? • Based on what was discovered, have students predict two or more materials they think would be magnetic and non-magnetic. If possible, test these predictions and discuss the reason behind their decisions. After the Lesson Answers Answers will vary depending on objects tested, but generally metal objects are attracted. Materials like aluminium cans, paper, plastic, wood or rocks neither attract nor repel. Additional Activities • Find buried treasures. In a small sand tray or box, hide a variety of magnetic materials. Secure small bar or button magnets to the end of a stick or ruler with tape. Students can only use the magnetic sticks to find the objects. Tell them the number of items buried and see who can find the most or who can find them all in the fastest time. • Make fish shapes on sturdy card. Attach a small magnet to a piece of string and tie the string to a pole or stick to make a fishing rod. Place a paperclip on the nose of each fish. How many fish can you catch? Make it a spelling or maths activity by attaching words or sums to the fish to match to certain sounds or numbers. • Test other objects around the room or outdoors that are attracted to a magnet. Predict the outcome and test for results Display Ideas • Make a large chart classifying drawings, pictures or words of things which are attracted to or unaffected by magnets. • Research toys or other objects we use that contain magnets. Draw and explain how the magnets work for each item (e.g. magnet sculptures, door bells, door latches, telephones, computers, some trains/tracks, tape recorders). Display the reports. ©R.I.C. Publications Low Resolution Images Display Copy 62 PRIMARY SCIENCE ~ R.I.C. Publications ® ~ www.ricpublications.com.au ISBN 978-1-925660-54-8
Magnets – Activity 1 Magnetic Attraction 1. Colour the box to show what happens when the two magnets get close to each other. a attract repel 2. b c Record which objects are attracted by magnets and which are not. 3. What is similar about the objects attracted to magnets? attract repel attract repel ©R.I.C. Publications Low Resolution Images Display Copy 4. a Name two objects that could be found outdoors that you think would be attracted to magnets. b Explain your choices. PRIMARY SCIENCE ~ R.I.C. Publications ® ~ www.ricpublications.com.au 63 ISBN 978-1-925660-54-8
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