Introduction
"What has all of this to do with my life? Why should I study
Physics?" If you think on these lines, the reply is, "Physics
has got enough to do with the real life. Do you want to be
the first person to invent a spaceship which travels faster
than light or a car that runs on water...? All of you have the
potential and realizing this starts right here, right now. You
can reason from basic physics concepts all the way to valid
conclusions about the world around you and the fun is in
this understanding. Physics is the foundation of all
engineering and technology. Could any engineer design a
spaceship, a LED "IV or a mobile phone which all of you use
without first understanding the basic laws of physics? When
we look around us at this fascinating, magnificent and
immense cosmos - look at the awesome, vast cosmos --
planets moving around the sun in an orderly manner,
phases of moon or movement of machinery parts all of
them are following certain laws. The inquiring and
imaginative human mind responds to this in many ways.
One such response is to observe carefully, look for
meaningful patterns, predict events, control environment.
Don't you want to be the in charge of your environment
with this powerful tool Physics? This study is also an
adventure. You will find it challenging, richly rewarding and
,satisfying. It will appeal to your sense, of beauty. Let’s take
a step forward by understanding 'Physical World'. In this
chapter, you will study what is physics; its scope and
excitement: physics. Technologic and society; fundamental
forces in nature and nature of physical laws.
WHAT IS PHYSICS?
Origin of the word, ‘Science’, is from Latin word, ‘Scientia’
which means, ‘to know. The Sanskrit word, ‘Vigyan’ also
has similar meaning, i.e., knowledge. The early civilisations
also made important contribution to its progress. Science is
a systematic (step by step) knowledge acquired through
observation and experience, aimed at understanding
natural phenomena in as much detail as possible. This
knowledge is used to predict and control our environment
the first step towards the discovery of science is a child’s
curiosity to learn about the world and disclose the secrets
of nature. Let this child in you be alive.
Scientific method involves
Systematic observation: It is setting up our study so that
we eliminate or reduce bias.
, Controlled experiment : It generally compares the
results obtained from an experimental sample against a
control sample, which is practically identical to
experimental sample except for the one aspect whose
effect is being tested (the independent variable), e.g., you
want to know whether light or dark clothing would be more
comfortable on a hot, sunny day. A controlled experiment
involves setting up two experimental conditions that are
exactly same except for a single factor that the scientist
manipulates. Here, the factor is colour. You will apply a
heat source, represented by a 60 W light bulb to different
coloured jackets and compare the temperature change for
each other.
Qualitative and quantitative reasoning: Qualitative
measurement is at the heart of growth of science as laws of
nature expressible in precise mathematical equations.
Mathematical modelling: It is the process of developing
a mathematical model (Description of a system using
mathematical concepts and language), e.g., predicting the
position of a vehicle from its initial position, direction and
speed of travel, using the equation that distance travelled
is the product of speed (constant) and time. It is common
"What has all of this to do with my life? Why should I study
Physics?" If you think on these lines, the reply is, "Physics
has got enough to do with the real life. Do you want to be
the first person to invent a spaceship which travels faster
than light or a car that runs on water...? All of you have the
potential and realizing this starts right here, right now. You
can reason from basic physics concepts all the way to valid
conclusions about the world around you and the fun is in
this understanding. Physics is the foundation of all
engineering and technology. Could any engineer design a
spaceship, a LED "IV or a mobile phone which all of you use
without first understanding the basic laws of physics? When
we look around us at this fascinating, magnificent and
immense cosmos - look at the awesome, vast cosmos --
planets moving around the sun in an orderly manner,
phases of moon or movement of machinery parts all of
them are following certain laws. The inquiring and
imaginative human mind responds to this in many ways.
One such response is to observe carefully, look for
meaningful patterns, predict events, control environment.
Don't you want to be the in charge of your environment
with this powerful tool Physics? This study is also an
adventure. You will find it challenging, richly rewarding and
,satisfying. It will appeal to your sense, of beauty. Let’s take
a step forward by understanding 'Physical World'. In this
chapter, you will study what is physics; its scope and
excitement: physics. Technologic and society; fundamental
forces in nature and nature of physical laws.
WHAT IS PHYSICS?
Origin of the word, ‘Science’, is from Latin word, ‘Scientia’
which means, ‘to know. The Sanskrit word, ‘Vigyan’ also
has similar meaning, i.e., knowledge. The early civilisations
also made important contribution to its progress. Science is
a systematic (step by step) knowledge acquired through
observation and experience, aimed at understanding
natural phenomena in as much detail as possible. This
knowledge is used to predict and control our environment
the first step towards the discovery of science is a child’s
curiosity to learn about the world and disclose the secrets
of nature. Let this child in you be alive.
Scientific method involves
Systematic observation: It is setting up our study so that
we eliminate or reduce bias.
, Controlled experiment : It generally compares the
results obtained from an experimental sample against a
control sample, which is practically identical to
experimental sample except for the one aspect whose
effect is being tested (the independent variable), e.g., you
want to know whether light or dark clothing would be more
comfortable on a hot, sunny day. A controlled experiment
involves setting up two experimental conditions that are
exactly same except for a single factor that the scientist
manipulates. Here, the factor is colour. You will apply a
heat source, represented by a 60 W light bulb to different
coloured jackets and compare the temperature change for
each other.
Qualitative and quantitative reasoning: Qualitative
measurement is at the heart of growth of science as laws of
nature expressible in precise mathematical equations.
Mathematical modelling: It is the process of developing
a mathematical model (Description of a system using
mathematical concepts and language), e.g., predicting the
position of a vehicle from its initial position, direction and
speed of travel, using the equation that distance travelled
is the product of speed (constant) and time. It is common
