* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download MAGNET MADNESS
Friction-plate electromagnetic couplings wikipedia , lookup
Electromagnetism wikipedia , lookup
Lorentz force wikipedia , lookup
Scanning SQUID microscope wikipedia , lookup
Neutron magnetic moment wikipedia , lookup
Magnetic monopole wikipedia , lookup
Magnetic nanoparticles wikipedia , lookup
Hall effect wikipedia , lookup
Electric machine wikipedia , lookup
Superconductivity wikipedia , lookup
Earth's magnetic field wikipedia , lookup
Magnetohydrodynamics wikipedia , lookup
Magnetic field wikipedia , lookup
Magnetoreception wikipedia , lookup
Magnetochemistry wikipedia , lookup
Multiferroics wikipedia , lookup
Galvanometer wikipedia , lookup
Faraday paradox wikipedia , lookup
Eddy current wikipedia , lookup
History of geomagnetism wikipedia , lookup
MAGNET MADNESS A Facilitator’s Guide to Magnetism Our Vision Canadians recognize that Science1 is intrinsic to their lives and acknowledge the fundamental importance of a quality Science education to prepare young people for our rapidly changing world. Our Mission Let’s Talk Science is striving to improve Science literacy through innovative educational programs, research and advocacy. We exist to motivate and empower young Canadians through Science education. Developed by Angelica Workman For ©1997 Let’s Talk Science Current Edition ©2002 Let’s Talk Science National Cornerstone Supporters: National Founding *Registered trademark of Imperial Oil Limited. Used under License. 1 Our Science includes life and physical sciences, technology, engineering and mathematics. To make a tax-deductible donation to improve Science literacy in Canada, please call Toll Free: 1-866-352-3060 or 519-474-4084 or visit our web site: www.letstalkscience.ca Let’s Talk Science, National Office Health Sciences Addition, H004 The University of Western Ontario London, Ontario, Canada N6A 5C1 Tel: 519-474-4081 Fax: 519-474-4085 Email: [email protected] www.letstalkscience.uwo.ca Charitable Number: BN88540 0846 RR0001 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission from LET'S TALK SCIENCE.. A. Description of Workshop Overview of Workshop Grade for Workshop/ Appropriate Age This activity is designed for use in Grade JK-3 classrooms or with children ages 4-9. Science Topics Magnetism Forces Through hands-on learning centres the students will determine which things are attracted to magnets and which are not. Explore magnetic attraction and repulsion. (Discover the force field around magnets; Grade 2 and 3 students will create a magnet and make their own compass) or (Students will discover the force field around magnets and make their own compasses). Overall Objectives To introduce magnets and where we can find them. To learn that a magnet has a north pole and a south pole and the rule about attraction. To introduce the domain theory. Page 3 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science B. How to Run This Workshop Physical Requirements You will need 3-4 stations set-up around the classroom. Materials and Set-Up Note: For more detail, see Kit List There are many choices for materials in this workshop. The materials listed below are just suggestions – substitutions and/or omissions are fine. Introduction Activity #1 – Testing Station Activity #2 – Fish and Turtle Station Ring magnets and pencil Magnets – horseshoe, bar Odd-shaped magnets Non-magnets Cow magnet Magnet wands – 1 per child or ring magnets Cups FISH Chalk-like magnet Compass Lodestone Not a Magnet Sheet – domains Domains of a Magnet Sheet Styrofoam Balloons Ball bearings Brass hooks or brass rings *Construction paper (cut in ¼ pieces) Fish tracer (made of cardboard) Pencils Fishing rod (pencil with fold back clips and a magnet) *Paper clips Scissors Crayons or markers TURTLES Aluminum foil *Turtle cut-outs Steel screws Pennies *Work Sheet for testing Pencils Scissors Needles or paper clips Magnet wands or ring magnets *Scotch tape Crayons or markers Container with water Compass Paper clips Corks Nails Paper clips *Consumable items Page 4 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Activity #3 – Strength Station Aluminum foil Cardboard Glass jar Metal lid Paper Styrofoam Wood Ring magnets – 1 or 2 per student Cow magnet Magnetic wands Bucket of washers Pencils *Work Sheets for strength testing Activity #4 – Mystery Powder Station Iron filings in containers (bottle, small cases and in mineral oil) Various magnets (ring, bar, magnetic wands…) Paper clips Magnetic chips Activity #5 – Discovery Station Magnetic marbles Magnetic chips Various magnets (ring, bar, magnetic wands..) Magnet toys Floating magnets Pencils *Consumable items Timing of Activity Part of Workshop: General Introduction Introduction to Topic Activity #1 Activity #2 Activity #3 Activity #4 Activity #5 Wrap-Up Suggested Timing: 5 min. 30 min. 10 min. 10 min. 10 min. 10 min. 10 min. 5 min. Cumulative Timing: 5 min. 35 min. 45 min. 55 min. 65 min. (OPTIONAL) 75 min. (OPTIONAL) 85 min. (OPTIONAL) 90 min. Page 5 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science C. Introduction to Topic Objectives of Introduction To To To To introduce what a magnet is. explain that magnets have poles. explain the rule about magnets (opposite poles attract). describe domains and their positions. Suggested Discussion, Q & A Who has magnets at home? Where are they? Refrigerator, toys What do you use them for? Playing, putting things up, keeping doors closed (cupboards and fridge) Can you think of anywhere else in your house you can find magnets? Television, telephone, VCR, stereo Magnets are very important to us and we use them in many places in our homes. Do magnets stick to things like glue would? No, magnets are attracted to things. (Hold up an odd shaped magnet.) Is this a magnet? Yes or No. One way to find out is to do an experiment. Let’s test it. Repeat with magnets and other steel objects that are not magnets. Keep going until students catch on to the fact that we only know if an object is a magnet by testing it, doing an experiment. If you like have volunteers come up to test the objects. Page 6 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science (Set-up two ring magnets so that they repel each other and they seem to be floating on a pencil) Present the students with a problem – I have two magnets that won’t stick together – can anyone come up and help me stick them together? (you can pretend to press really hard on them so that they might stick together this way) (Have a few students come up to the front and try and stick them together, until someone figures it out!) What did he/she do to stick the magnets together? They turned one magnet over. Why do they stick now? There are two sides on a magnet, they are called the North pole and the South pole. The rule about magnets is that only N and S like each other – Opposites attract! (Have everyone repeat the rule and ensure they understand the concept of opposites by asking:) What is the opposite of up? DOWN What is the opposite of fast? SLOW What is the opposite of North? SOUTH (Have students hold their hands out and pretend that their hands are the poles of a magnet.) If my right hand is a North pole and my left hand is a South pole, what would happen? They would stick together (attract) – clap hands together. If my right hand is a north pole and my left hand is another north pole, what would happen now? They would stay away from each other (repel) – hands won’t come together. (Keep giving them combinations of North and South poles to test their knowledge of this rule.) Page 7 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Now, if magnets have a North pole and a South pole, what is the biggest magnet in the whole wide world? THE EARTH! It has a North pole and a South pole! The core of the Earth is made of lodestone (mostly iron) – show Sample of lodestone/magnetite. Does anyone know what a compass is? What does a compass do? A compass shows us which direction is North. The needle of a compass is attracted to the Earth’s magnetic pull. Magnets have a force that we can’t see that attracts or repels certain things (pulls them towards, or pushes them away) and does nothing to other things. To see what that force can do we use iron filings. (Hold a magnet wand against a clear container filled with iron filings) Do you see the magnetic field? YES! When you play with the magnets today, be careful not to drop them! D. Activities CHOICE: Everyone should do Activity #1 and Activity #2 (either Fish or Turtles). The other activities are choices. You should do at least 3 activities, 4 is optional. You can also combine activities together. CHOICE: You can set these activities up in stations or do them as a large group. Page 8 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science ACTIVITY #1: TESTING STATION (10 min.) Work Sheet: JK-Gr. 1 – Magnet Experiment Data Sheet #1 (8 boxes) Gr. 2-3 – Magnet Experiment Data Sheet #2 (10 rows) Objective of Activity To find out what magnets like and what magnets don’t like. Suggested Instructions, Q & A At this station, you will take a magnetic wand or ring magnet and dip it into the cups full of certain materials, and see if they stick to the magnet or not. If you are using Magnet Experiment Data Sheet #1: Record your results by circling the pictures that the magnets stick to. If the magnet sticks, circle the picture, if the magnet doesn’t stick, don’t circle the picture. (or colour, or write YES/NO….) If you are using Magnet Experiment Data Sheet #2 – explain what a prediction is. Record your results in the Test column by circling Yes or No (Yes if your magnet sticks, No is it doesn’t stick.) ACTIVITY #2: FISH AND TURTLE STATION (10 min.) Work Sheet: FISH: no work sheet, construction paper with fish tracer TURTLE: Make a compass, single turtles to cut out Objective of Activity FISH – to use a magnet to pick up an object with metal attached to it. TURTLE - to demonstrate how a compass works - to demonstrate how to make a metal object magnetic. Page 9 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Suggested Instructions, Q & A FISH Everyone will trace a fish onto a piece of construction paper and cut it out. Put your name on the fish and decorate it. Attach a paper clip to the mouth of the fish. Throw your fish into the pond (onto the floor/carpet). Take your fishing rod (pencil with a string and a fold-back clip on the end with a broken magnet) and try and catch your fish! TURTLE Cut out your turtle. DELIVERY HINT: Have students colour their turtle front and back with wax crayon (to make it waterproof). Take a needle (or paper clip) and stroke it with a magnet at least 50 times in the same direction. Try and pick up a paper clip. If your magnet (the needle) seems weak, stroke it another 50 times, until it picks up the paper clip. DELIVERY HINT: If the needle still doesn’t pick up the paper clip, have students try holding the other end of the needle. Tape the needle (or paper clip) to the underside of the turtle. Float your turtle in the dish of water. Pay close attention to which way the head of the turtle points (North or South). If the turtles are made with paper clips, the students can keep them. If they are made with needles, take the needles off and then they can keep the turtle if they want. CHOICE: Give the teacher copies of the “Make a Compass” sheets for the students to take home and make later. Page 10 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science ACTIVITY #3: STRENGTH STATION – What can magnets work through? (10 min.) Use Magnetic Strength Work Sheet Objective of Activity To demonstrate how strong magnets can be. Suggested Instructions, Q & A Put a variety of materials (aluminum foil, cardboard, glass jar, metal lid, paper, Styrofoam, wood….) out for students to test. Have two ring magnets for every child to test the materials with, or one ring magnet and a washer/paper clip. Put one magnet on the top of the material, and then put the other magnet/washer on the bottom. Are the magnets still attracted to each other or is the magnet attracted to the washer? If they are, circle YES. If they aren’t, circle NO. Have a bucket of metal washers. Have the students test cow magnets, ring magnets and a magnetic wand to see how many washers each of these magnets can hold. Try lining up the washers one by one and not just sticking the magnet in the container to see how many bunch up. ACTIVITY #4: MYSTERY POWDER (10 min.) No Work Sheet Objective of Activity To demonstrate magnetic fields through iron filings. Suggested Instructions, Q & A Page 11 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Set out containers of iron filings with various magnets and have students place the magnets against the containers and move them around to see the magnetic fields. Have the students try and guess what this mystery powder is. If they think it is a magnet powder, ask them how we tested to see if an object was a magnet in the introduction of the workshop. We had to test it! Have them test the powder the same way. If the powder doesn’t stick to the blackboard, ask them what else it could be? (sand, dirt…) ACTIVITY #5: DISCOVERY STATION (10 min.) No Work Sheet Objective of Activity To allow students time to feel attraction and repulsion with different magnets. Suggested Instructions, Q & A Put out a variety of materials for the students to play with (magnetic marbles, magnetic chips, magnetic wands, ring magnets, pencils/dowels, any toys…). E. Wrap-Up (Go over what students learned at each activity.) What do magnets like? Metal Did your magnet stick to the penny? No Is the penny made of metal? Page 12 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Yes, copper. How can you tell if something is a magnet? Test it! So, do magnets stick to all metals? No, they also didn’t stick to the aluminum or brass. Magnets are most attracted to iron, cobalt and nickel. (Go over the rule about magnets – opposite poles attract, like poles repel.) (If you have extra time to fill – you can play this game) Magnet Domain Role Play Game Is every object a magnet? No, only some objects are magnetic. Inside a magnet there are tiny magnetic regions called domains. All of these domains face the same direction. (Hold up the Domains of a Magnet sheet – or draw something similar on board.) As you can see on this picture of a magnet, all of the domains face the same direction. You can see that all of the red circles are facing one side of the page and all of the blue circles are facing the other side of the page. In every magnet there are domains, which line up in the same direction. (Hold up the Not a Magnet sheet.) This picture shows an object that is not a magnet. Can you see how each of the red and blue circles are facing different directions? The domains are not facing the same direction as they did on the magnet sheet. Let’s try to become a magnet. Everybody stand up! We are all going to imagine now that we are the domains – the circles and lines we saw on the pictures. Your head is the red circle and you feet are the blue circle. Page 13 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science OK, everyone jump on one foot. Turn around three times. Smile as big a possible. Now carefully lie down on the floor/carpet. (Once everyone is settled and lying down ask them to lift their heads.) Is everyone facing the same direction? No! So are we a magnet now or not? Are all the domains facing the same direction? We are not a magnet. Our heads are facing different directions. Let’s try this again. Jump on one foot. Turn around three times. Smile as big as possible. Now everyone carefully lie down with your head facing (pick a point in the room – the door, the blackboard, the facilitator, the wall…). (Once everyone is settled and lying down ask them to lift their heads.) Is everyone facing the same direction? Yes. So we are now a magnet. Our heads are like those red circles and just like in the picture, all of our domains are facing the same direction! (Have them regroup and review the pictures. Remind them when they were a magnet and when they were not.) Has anyone ever dropped a magnet before? What happens? It is not magnetic anymore. It is not magnetic anymore because the domains have moved around and no longer face the same direction. In a dropped magnet the domains face all directions, just like you did the first time you were lying on the ground. When you play with the magnets today, be careful not to drop them! Page 14 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science F. Glossary Alloy A mixture of two or more elements (usually metals). Compass A small magnet (needle) pivoted at its central point that aligns itself so that its North-seeking end points to the Earth’s magnetic North pole. Cow Magnet A large magnet shaped like a pill so that it can be given to a cow to swallow. If the cow has eaten any nails, screws…., it will attract these so it won’t hurt the cow’s stomach. Domains Regions in a magnet which, according to the domain theory of magnetism, are made up of many tiny molecular magnets called dipoles. Electromagnet A temporary magnet produced by an electric field. Ferromagnetic A material which can be magnetized strongly, such as iron, cobalt and nickel and their alloys. Magnetite A black mineral form of iron oxide crystallizing in the cubic system. It is strongly magnetic and some varieties, known as lodestone, are natural magnets; these were used as compasses in the ancient world. Magnetic Field A field of force that exists around a magnet or a current-carrying conductor. Magnetic Force A force between two moving charges. These moving charges can be electric currents or electrons moving around the nucleus. Page 15 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science Magnetic North The Earth has a magnetic field which acts as though there were a giant bar magnet in its centre, lined up approximately between its geographic North and South poles, although the angle is constantly changing. The needle of a compass points towards a point called Magnetic North. North Pole (or North-seeking Pole) A north pole is the end of a magnet which when suspended freely points to the north (magnetic north). Pole A point in a magnet at which its magnetic force appears to be concentrated. South Pole (or South-seeking Pole) A south pole is the end of a magnet which when suspended freely points to the south. G. Background Information Magnetism Magnetic forces are created by the movement of charged particles like electrons (intimately related to electricity). The greatest evidence of magnetism is the attractive or repulsive force observed to act on iron, cobalt and nickel. Similar, more subtle, effects of magnetism are found in all matter and these have provided important clues to the structure of matter at the atomic level. Law of Magnetism This states that like poles of two magnets (two north poles or two south poles) repel one another, and unlike poles attract one another. Magnetic Domains These are tiny magnetic regions found in magnetic substances such as iron. When all of the domains are facing the same direction (parallel alignment) we have what we know as a typical magnet. If the magnet is dropped or heated, the domains will be knocked around into a random array and the substance will no longer be a magnet. Page 16 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science We can line the domains up by stroking a substance with a strong magnet or passing an electric current through the substance. NOT A MAGNET MAGNET (represents a domain) Applications The electromagnet is the basis of electric motors and the transformer. New magnetic materials are important in computers, which have a series of magnetic regions that make up their memory. Memories are created using bubble domains in garnets. These domains are actually tiny regions of magnetization that are either parallel or anti-parallel to the overall magnetization of the substance. Bubble direction is the key and will indicate either a one or a zero, representing the units of the binary code used in computers. Magnetic materials are used in tapes, disks and other media on which data is stored. Page 17 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science H. Suggested Resources Websites Cool Experiments with Magnets www.execpc.com/~rhoadley/magindex.htm Books Ardley, Neil. (1991). The Science Book of Magnets. Canada: Doubleday Canada Ltd. ISBN: 0-385-25322-2 VanCleave, Janice. (1991). Janice VanCleave’s Physics for Every Kid. John Wiley and Sons Inc. ISBN: 0-471-52505-7 Levenson, Elaine. (1994). Teaching Children about Physical Science. U.S.A.: TAB Books. ISBN: 0-07-037619-0 Page 18 of 18 In-class workshops, Magnet Madness ©2002 Let’s Talk Science