Magnets and Magnetic Fields

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Magnets & Magnetic Field

Magnets- able to exert a force on a nearby or a close object

Magnets have two poles on opposite ends;

- South Pole

- North Pole

Rules of Magnetism

-The alike poles attract so north-north and S-S

-Opposites repel

They are non-contact forces-magnets don't need to physically touch to affect each other

Magnetic materials -substances which are attracted to magnets , not to each other

Examples of magnetic substances :

- Nickle

- Cobalt

- Iron

- Steel

Non-magnetic materials

- Copper

- Aluminium

- Zinc

Permanent magnetism and Induced Magnets

- What is a permanent magnet:

-Usually made from the magnetic material iron

- It always causes a force on other magnets

- It produces its own magnetic field

- Its magnetic field can easily be turned on and off- always there

Example of permanent magnet - Bar Magnet

Permanent Magnet:

- Able to attract or repel another permanent magnet

- Only attract a magnetic material or substance

Induced Magnets

Magnetic materials which become a magnet when placed in a magnetic field

- Induced magnet only turns to a magnet when put in a magnetic field. quickly loose their magnetism when removed from magnetic field and stop producing a magnet field

When current flows through a wire - produces a magnetic field around the wire

What is a magnetic field:

A region or an area where other magnets or magnetic materials experience a force

- Can be detected using magnetic compasses