Question

Collect information about the magnetism of the earth.

Answer 1

Magnetism of the Earth:

• The earth itself behaves like a giant magnet. This property is called earth magnetism or geomagnetism.
• A piece of magnetite (a natural magnet), when hung freely, always settles in the north–south direction. This is because of the earth's magnetism.
• The earth has magnetic poles — a magnetic north pole and a magnetic south pole. These are located near the geographic north and south poles but do not exactly coincide with them.
• The mariner's compass works on the principle of earth's magnetism. It was invented because magnetite rocks always pointed north–south, helping travellers find directions through unknown regions.
• Because of earth's magnetism, a freely suspended magnet (like the needle of a compass) always comes to rest in the north–south direction.
• China and Europe knew about this property of magnetite long ago and used it as a lodestone (leading stone) for finding directions while travelling.

Key Point: Just as a bar magnet has a north pole and a south pole, the earth also has a magnetic north pole and a magnetic south pole due to its magnetic field.