Page 28 - Physics

Physics for Secondary Schools

Laws of Physics fl oating object displaces its own weight of fl uid in
In physics, a law is a scientifi c which it fl oats’
statement that describes a
physical phenomenon under
certain conditions in nature.
Physical laws provide important
insight into the nature of the
universe, and they are developed
from several observations in
nature. However, physical laws
do not explain the mechanism
by which a phenomenon occurs.
Physical laws are applicable to
all objects regardless of scenario
but are only meaningful within
certain contexts. Examples of
physics laws are the Hooks law Figure 1.24: Illustrates the law of fl oatation
and the law of fl oatation.
Principles of physics
Hooke’s law In physics, a principle is a general rule or explanation

Hooke’s law is a law of physics of how a specifi c physical phenomenon occurs.
that explains the force needed Essentially, a principle is a fundamental truth
to extend or compress a spring that forms a foundation for explaining a physical
by distance .x It states that phenomenon in nature. In addition, principles
“provided the elastic limit is describe some specifi c fundamental concepts.
not exceeded, the extension Developing a principle requires more explanations
is directly proportional to the than the requirement for a physical law. It is for this
force applied.” reason; that physicists need to follow the method of
scientifi c investigation when developing a physical
The law of fl oatation principle. Examples of physics principles are

The law of fl otation is a crucial Pascal’s principle, Archimede’s principle and the
principle for understanding why principle of conservation of energy.
certain objects rise or submerge Archimedes’ principle
in fl uids. It determines whether
the object will fl oat or sink Archimedes’ principle is a fundamental concept in
based on its density relative to fl uid mechanics, named after Greek mathematician
the surrounding medium. The and scientist Archimedes. The principle explains the
law of fl oatation states that ‘a buoyant force experienced by an object immersed in

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Student’s Book Form One

Physics Form 1 Final.indd 22 16/10/2024 20:55