Back to: Jss3 Basic Science
WEEK: 7 & 8
Magnets are things that can pull iron and steel toward them. Magnets were found for the first time in China more than 2,000 years ago. They were called “loadstones,” and it turned out that they were iron oxide. Magnetism is the force that makes iron and steel stick to a magnet. You will learn about the laws of magnetism, magnetic poles and fields, and how to take care of
Meaning Of Magnet
A magnet is a substance or material that pulls iron and other ferometals toward it. Magnetism is the ability of a material to pull an iron-based metal toward it.
Lodestones are magnetised rocks. Magnetite (Fe3O4) is a kind of iron oxide that is used to make them. Then, a piece of iron is called a lodestone. The lodestone seems to have been found first by the Chinese. Chinese sailors used lodestone as an early kind of compass. This is because a magnetised stone will be drawn to the pole of the earth’s magnetic field. Also, when it’s hanging in the air, it slowly turns to face the pole.
Laws Of Magnetism
The first magnetic law
This states that like poles repel. That is like how poles don’t attract. each other. This means that if you bring the north-seeking pole of one magnet closer to the north-seeking pole of another magnet, they will repel each other. The same is true if you put together two north poles that want to go south.
The second law of magnetism
The second law of magnetism: States that unlike poles attract that is poles that are different from each other magnet. This means that if you bring the north-seeking pole of one magnet closer to the south-seeking pole of another magnet, they will attract each other.
Magnets have two poles, one that pulls toward the north and one that pulls toward the south. If you tie one end of a rope to a magnet and hold the other end, you can find out where the two poles are. The end of the magnet that points to the geographical north is the north-seeking pole. The end of the magnet that points to the geographical south is the south-seeking pole. There are two rules that describe how magnets work.
This is a state that happens near a magnet and is marked by the presence of magnetic poles. It can also be thought of as the area around a magnet where magnetic force can be felt.
Magnets can lose their magnetism when:
a. they are hit hard;
b. they are run with an alternating current; and
c. They are pointing in an east-west direction.
The Care Of Magnets
Magnets need to be taken care of so that they don’t lose their ability to attract things. Magnets need to be taken care of in the following ways.
- Magnets should be stacked with other magnets that are the same kind, and they shouldn’t touch the edge of a flexible magnet because that can change the polarity.
- Many of the Polar Power magnets can have their covers replaced. This is because magnet covers and materials can wear out and tear over time.
- They should be cleaned by wiping them gently with a damp, soapy sponge and should not be put in water.
- The magnetic signs flay should be spread out in order to store them on a metal surface that is smooth.
- They should not be exposed to high temperatures or brought near fire because doing so can cause damage to them.