Exploring Magnets · Lesson 1 of 6
Magnets and Magnetic Materials
“Explore where magnets are found, how their shapes vary, and which everyday materials respond to them.”
• Recognise common natural and artificial magnets and identify several familiar magnet shapes. • Predict and test whether everyday materials are attracted by a magnet. • Distinguish magnetic materials from non-magnetic materials using observations. • Name common magnetic metals and explain why an object's material matters more than its shape.
Magnets Around Us
Magnets are not limited to laboratories. They may be hidden inside pencil boxes, purses, toys, refrigerator decorations, door catches and classroom equipment. In each case, the magnet is useful because it can attract certain materials or hold two parts together without glue, string or a latch.
Long ago, people discovered naturally occurring magnetic rocks called lodestones. Later, they learnt to make magnets from suitable pieces of metal. Magnets made deliberately for use in tools, toys and devices are called artificial magnets.
A naturally occurring magnetic rock that can attract magnetic materials.
A magnet made by people from suitable magnetic material for a particular use.
Magnets Can Have Different Shapes
A magnet's shape is chosen to suit the job it has to do. A straight bar is convenient for experiments, a U-shaped magnet brings two poles close together, and a ring magnet can fit around a rod or axle. Although their shapes differ, they all show the same basic magnetic behaviour.
Which Materials Are Attracted?
A useful way to study magnets is to test objects made from different materials. Before testing, make a prediction. Then bring the magnet close without forcing the object to touch it. The comparison between prediction and observation is important because science depends on evidence rather than guesses.
Collect objects made from materials such as wood, rubber, plastic, glass, iron and other metals. Predict whether each object will be attracted by a magnet. Test them one by one and record what actually happens. Keep the magnet at a similar distance each time so your observations are easier to compare.
| Object or material | Prediction | Observation | What it suggests |
|---|---|---|---|
| Wooden pencil | Will it be attracted? | Usually no | Wood is non-magnetic. |
| Rubber eraser | Will it be attracted? | No | Rubber is non-magnetic. |
| Iron nail or steel pin | Will it be attracted? | Yes | Iron-containing material is magnetic. |
| Plastic ruler | Will it be attracted? | No | Plastic is non-magnetic. |
Magnetic and Non-magnetic Materials
The important feature is not whether an object is hard, shiny, heavy or made of metal. The key question is whether the material itself is attracted by a magnet. Iron is magnetic. Nickel and cobalt are also magnetic, and some combinations containing magnetic metals can also be attracted.
A material that is attracted towards a magnet.
A material that is not attracted towards a magnet.
Not every metal behaves the same way near a magnet. The safe conclusion is based on the observed material, not simply on whether the object looks metallic.
Problem
A shiny iron paper clip and a shiny aluminium-foil ball are brought near the same magnet. The paper clip is attracted, but the foil ball is not. What should you conclude?
- 1.Both objects look metallic, so appearance alone cannot tell us whether an object is magnetic.
- 2.The paper clip's material is attracted by the magnet, so it behaves as a magnetic material.
- 3.The foil ball does not show attraction in this test, so it should not be classified as magnetic merely because it is a metal.
Check Your Understanding
Quiz
Which statement best describes a magnetic material?
Which object is most likely to be attracted strongly by an ordinary classroom magnet?
Why should we record both a prediction and an observation in a materials test?
Which pair contains two magnetic metals named in this lesson?
A magnet is hidden inside a purse clasp. This is an example of which type of magnet?
Practice Problems
- List five objects around your home or classroom that might contain magnets. For each, state what the magnet helps the object do.
- Make a prediction table for six materials before testing them with a magnet. After testing, add an observation column and compare your predictions.
- Explain in your own words why 'all metals are magnetic' is not a reliable rule.
- A student tests a steel pin, wooden bead, plastic cap and iron screw. Predict which are likely to be attracted and justify your answer using the material of each object.
- Draw three different magnet shapes and label them. Explain one reason why magnets might be manufactured in different shapes.
- Write one sentence each defining magnetic material and non-magnetic material without using the words 'sticks' or 'does not stick'.
Key Takeaways
• Magnets may be natural, such as lodestones, or artificial, made for particular uses. • Magnets can have different shapes, including bar, U-shaped and ring forms. • A magnetic material is attracted towards a magnet; a non-magnetic material is not. • Iron, nickel and cobalt are examples of magnetic metals. • Scientific conclusions should come from observations, not from an object's appearance.
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Next · Lesson 2
Magnetic Poles and Where Magnetism Is Strongest