Page 101 - Physics_Form_2

Magnetism

Electron iron nail, water, wooden
toothpick, chalk, aluminium
Orbit
Spin foil, lead (graphite) pencil,
some sand

Procedure
FOR ONLINE READING ONLY
Nucleus 1. Place each of the materials close to
a bar magnet.
2. Note down your observations.
Figure 3.2: Orbit of a spinning electron
around the nucleus of an atom Questions
(a) Which materials were attracted to
In many atoms, these magnetic effects the magnet, and what do they have
cancel each other, while in other atoms in common?
they do not cancel completely. (b) Why do you think some metals are

attracted to the magnet while others
Magnetic and non-magnetic materials are not?
When a magnet is brought near different (c) Based on your observations, how
objects, some will be attracted or can you classify magnetic and non-
repelled, and others will not. Objects that magnetic materials?
are attracted are said to possess induced
magnetism. The process by which a Metallic materials like iron, nickel and
material becomes a magnet due to its cobalt become magnetised when exposed
closeness or contact with a magnet is to the influence of a magnet. They are thus
called induction. The induced magnetism magnetic. Magnetic materials are those
can be temporary or permanent upon the which can be magnetised by even weak
removal of the magnet in contact. The magnets. Materials that are attracted to a
nature of the material being magnetised
determines how long the induced magnet and can be strongly magnetised
magnetism lasts. For example, iron are called ferromagnetic materials.
exhibits temporary magnetism while Ferromagnetic materials contain either
materials like steel tend to retain their iron, nickel or cobalt. These materials
magnetism for a long time. Materials are grouped as magnetically hard or soft
which are not affected by a magnet are depending on how well they retain their
called non-magnetic materials. magnetism when magnetised.

Magnetically hard materials such as steel
Activity 3.1 do not readily lose their magnetism, though
they are difficult to magnetise. They are
Aim: To classify magnetic and used to make permanent magnets. On
non-magnetic materials the other hand, soft magnetic materials

Materials: bar magnet, knife, blade, like iron can be easily magnetised, but
copper rod, paper, glass rod, they tend to lose their magnetism easily.
As a result, they are used in the cores

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Physics Form 2 Final.indd 95 25/10/2025 10:26