That is, they are forced together this is called attraction. If two magnets are pointing with like-poles together a south pole to a south pole OR north to north , then stored-up energy will decrease if they move apart. So our rule says the magnets will be pushed in the direction that decreases the amount of stored-up energy. That is, they are forced apart repelled.
Earth is also surrounded by a gravitational field which also contains stored up energy. Unlike magnetism, gravity never repels because gravity only points one way. There are no north and south poles for gravity. Read more: Earth's magnetic heartbeat, a thinner past and new alien worlds. The energy needed to pull the magnets apart comes from you, and you get it from the food you eat.
And the plants or animals you eat get their energy from other plants and animals, or from the Sun. All energy comes from somewhere. Hello, curious kids! Ask an adult to send your question to us. They can:. This is due to the principles of magnetism. To determine if an item has any magnetic properties, put it near iron filings or even a paperclip.
If the iron is either attracted or repelled, the item in question can be considered a magnet. While it is possible to find certain types of rocks and minerals that are natural magnets, most magnets we see are manufactured. The processes of magnetism occur on the atomic level. Magnets are surrounded by an invisible magnetic field that is made by the movement of electrons, the subatomic particles that circle the nucleus of an atom.
The hyperactivity of these electrons gives magnets their ability to attract and repel. Natural and manufactured magnets that have magnetic properties all the time are considered permanent magnets.
All magnets have two ends, which are commonly referred to as north and south poles. The determining factor of whether a magnet attracts or repels is the pole. Magnets attract when a north pole is introduced to a south pole. If like poles are introduced, either north to north or south to south, the magnets repel.
Permanent magnets can also cause a reaction with nonmagnetic items, such as metals and even some liquids. These items are dubbed temporary or soft magnets. They have magnetic properties for only the period of time near the magnetic field of other magnets.
Magnets in history Magnetic force has been known for a very long time. The Ancient Greeks knew that certain rocks, called lodestones or leading stones, as they were used for finding direction attracted some metals, and that they could be used to find direction on the oceans. It wasn't until , when a Frenchman named Petrus Peregrinus investigated lodestone scientifically, that the two ends, or poles, of the magnet were found to be different.
Magnetic Island, off the coast of Queensland, was so called because Captain Cook's compass behaved oddly when approaching the island. He thought that there must have been magnetic material in the island, hence the name. What is happening inside a magnet?
Common bar magnets are largely made of iron. Inside the iron bar are tiny magnetic regions called domains. When a strong magnet is present, these domains line up with most of the north seeking ends in the same direction.
This is what causes the poles to be different. One end of a magnet is called the south-seeking pole and the other north-seeking. This description is used because the Earth is described as though it has a great magnet inside it, and the Antarctic region has been called the South Pole - these are used as reference points.
A bar magnet placed in Earth's magnetic field will align itself so that its south seeking pole points to Earth's South magnetic pole and the north seeking pole points to Earth's North magnetic pole.
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