INTRODUCTION TO PHYSICS

WHAT IS PHYSICS?
Physics is a physical science that deals with the study of matter and energy. It is also the branch of science concerned with the study of properties and interactions of space, time, matter and energy.
WHY STUDY PHYSICS
(i)                 Analytical skill: Studying Physics will enhance your ability to think clearly, to pay attention to detail and to construct logical reasoned arguments.
(ii)               To be scientifically literate.
(iii)             Problem solving skill: It gives the ability to solve practical problems.
 BRANCHES OF PHYSICS
(i)                 Mechanics: Study of the force which are acting on matter as well as the motion.
(ii)               Electricity: Study about the motion of electric charge.
(iii)             Electromagnetism: It is concerned with the production and effects of magnetism through electricity and electricity through magnetism.
(iv)             Field: It explains the origin, nature and properties of field as gravitational field, electromagnetic field etc.
(v)               Solid state Physics: It is concerned with the matter having crystalline structure with particular arrangement of atoms.
(vi)             Nuclear Physics: it deals with structure properties forces and physical properties force and physical reaction between the nucleus of elements and also with energy and elementary particle of nucleus.
(vii)           Atomic Physics: It dea ls with the structure and properties of a atom if different elements determined by their electrons.
(viii)         Molecular Physics: It explains the structure of matter on the basics of molecules.
(ix)             Astor Physics: It concerned with location, motion and other physical properties of planets, star etc. with the application of laws of modern Physics.
(x)               Geo Physics: It is related to the structure, properties and the motion of the earth.
      (xi)      Bio Physics: It is related to the structure and function of living organism by applying physical laws.
SYSTEME INTERNATIONAL UNIT (S.I.)
This is a system of unit known as international system unit. This is used for all branches of Physics. For example:
Quantity
Unit
i
Length
Meter
ii
Mass
Kilogram
iii
Time
Second
iv
Electric current
Ampere
v
Temperature
Kelvin
vi
Force
Newton

FUNDAMENTAL OR BASIC QUANTITY
These are quantities from which other quantities are derived. There are three major basic quantities which are;
(i)                 Mass
(ii)               Length
(iii)             Time.

Other quantities are Temperature, Electric current etc.
FUNDAMENTAL OR BASIC UNITS
These are the units of the fundamental or basic quantities. These are shown in the table below;
Quantity
Unit
Unit abbreviation
i
Mass
Kilogram
Kg
ii
Length
Meter
M
iii
Time
Second
S
iv
Temperature
Kelvin
K
v
Electric current
Ampere
A

DERIVED QUANTITIES
These are formed by the combination of two more fundamental or basic quantities. Examples are; Speed, velocity, Acceleration, Force, Work etc. Their respective units are also derived from fundamental or basic units i.e. meter per second (m/s or ms-1), (m/s or ms-1), meter per second square (m/s2 or ms-2), Newton (N) and Joule (J).

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