Magnets, Gr. 3-4
| | Magnets are fun. Spend time exploring how magnets affect one another. Make up games to play using magnets.
Have
you discovered that a compass needle is a magnet? It is a great tool
for testing other objects to see if they are magnetized. If something
attracts one end of the compass needle and repells the other end of the
needle, the object is showing it has poles and is a magnet. Sometimes
objects have stood so long in one place that the earth's magnetic field
has caused them to become magnetized. Test metal file cabinets, metal
door frames and other steel objects that have not been moved in a long
time. If you hold a compass near one end of the object, look to see
which end of the compass needle points to the object. Move the compass
slowly along the length of the object. If the compass needle suddenly
swings around so that the other end of the needle points to the object,
you know the object is magnetized. Try it out.
Do you think magnetism can go right through things? Click on the left navigation page - Testing What Magnetism Can Pass Through - to see how to make a tester to find out.
There are some good websites for finding out more about magnets. One good site to start with is provided by How Products are Made which has basic information about magnets that many students will find helpful. Adults and more advanced students will enjoy Permanent Magnet Design Guidelines.
NASA has some slightly more advanced information about magnetism which is good background for teachers.
So,
have fun learning about this very important force in our lives.
Remember, magnets should be kept away from TV screens, computer
monitors, and all forms of magnetic information storage such as floppy
disks, audio cassettes, VCR tapes and credit cards.