Magnetism

Summary

Magnetism involves the study of magnets, magnetic fields, and electromagnets. Magnets have unique properties and can be permanent or temporary, while electromagnets can be turned on and off.

• Magnetism — the force exerted by magnets when they attract or repel each other. Example: Lodestone attracting iron pieces.
• Permanent Magnet — a magnet that retains its magnetic properties even when not in a magnetic field. Example: Bar magnets.
• Temporary Magnet — a magnet that only exhibits magnetic properties when in a magnetic field. Example: Iron becoming magnetic near a magnet.
• Magnetic Field — the area around a magnet where magnetic forces can be detected. Example: Field lines around a bar magnet.
• Electromagnet — a type of magnet whose magnetic field is produced by the flow of electric current. Example: A coil of wire with a current passing through it.

Exam Tips

Key Definitions to Remember

• Permanent Magnet: A magnet that maintains its magnetism without an external field.
• Temporary Magnet: A magnet that only shows magnetism when in a magnetic field.
• Electromagnet: A magnet created by electricity flowing through a coil.
• Magnetic Field: The region around a magnet where magnetic forces act.

Common Confusions

• Confusing permanent magnets with electromagnets.
• Misunderstanding the direction of magnetic field lines.

Typical Exam Questions

• What word best describes bar magnets? Permanent
• What do opposite poles do? Attract
• Specifically in which direction do the lines run in a field diagram? North to south

What Examiners Usually Test

• Understanding of the properties of magnets and magnetic fields.
• Differences between permanent magnets and electromagnets.
• Ability to interpret magnetic field diagrams.