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2. Science is a way of understanding how the world and a lot of
things work. For example, the rock that attracts iron is known to be
the black oxide mineral named magnetite, after the city of
Magnesia. This magnetite which acts as a natural magnet is called
lodestone and is used as a leading stone or compass.
The ancient Greeks and Romans knew as well as we do that
lodestone (an iron-rich mineral) can attract other pieces of iron. On
the other hand, the ancient Chinese made magnetic compasses set
in intricate wooden inlays for their practice of Feng Shui (the art of
carefully arranging a room or an environment thousands of years
before interior designers came on board).

3. Magnetic Materials
Many of us are not familiar with a natural magnet called
lodestone. It strongly attracts iron and steel as well as cobalt and nickel.
These solid substances are said to have ferromagnetic properties or
magnetic properties.
A magnet is an object or material that attracts certain metals. It
can also attract or repel another magnet. Chinese were the first to
discover that lodestone or natural magnet has two magnetic poles.
These are the North-seeking (N) and South-seeking pole.

4. When magnets are placed near each other, opposite poles
attract and like poles repel each other. This is called magnetism.
Magnetism is a force of attraction or repulsion that acts as a
distance. It is due to the magnetic field, which is caused by moving
electrically charged particles or is inherent in magnetic objects such
as magnets. Various electrical devices make use of magnets.

5. There are six basic facts about magnets:
1. A magnet has two ends called poles, the north pole or north-
seeking pole and the south pole or the south-seeking pole.
2. Like poles repel, unlike poles attract.
• Attraction – When two magnets or magnetic objects are close
to each other, there a force that attracts the poles together.
• Repulsion – When two magnetic objects have like poles facing
each other, the magnetic force pushes them apart.

6. Attraction and Repulsion of Magnets

7. Like and Unlike Poles

8. 3. A magnet creates an invisible area of magnetism all around.
4. The north pole of a magnet points toward the Earth’s north pole
and vice versa, because Earth itself contains magnetic materials and
behaves like a gigantic magnet.
5. If you cut a bar magnet in half, half has its own north and south
poles.
6. If you run a magnet a few times over a unmagnetized piece of a
magnetic material, it turns into magnetic as well.

9. Types of Magnets
• Permanent Magnets
Permanent magnets are made of materials that are
permanently magnetic. This being the case, their electrons will not
change directions
Examples:
• Magnetite is a magnetic material found in nature. It is
characterized as relatively weak.
• Alloys are permanent magnet that are made up of two
different chemical elements, one of which is metal.

10. Temporary Magnets
Temporary magnets only exhibit signs of magnetism when
exposed to strong magnetic fields. When temporary magnets are
exposed to permanent magnets, their atomic composition adjusts so
that the poles point in the same direction. After that, they take on
magnetic properties and become either attracted or repelled by other
magnets.
Electromagnets
Electromagnets run on electricity. The strength on electromagnet
can easily be changed by changing the amount of electric current that
flows by it. By wrapping around a wire around an iron or steel core and
running an electric current through the wire, metal, can be magnetized.

11. Shapes of Magnets
Magnets come in different shapes, such as square,
horseshoe, bar, sphere and others.
Square Magnet Bar Magnet

12. Horeseshoe Magnet