CONCEPTS OF PHYSICS
[VOLUME 1]
H C VERMA, PhD
Retired Professor
Department of Physics
IIT, Kanpur
, Dedicated to
Indian Philosophy & Way of Life
of which
my parents were
an integral part
, FOREWORD
A few years ago I had an occasion to go through the book Calculus by L V Terasov. It unravels intricacies
of the subject through a dialogue between Teacher and Student. I thoroughly enjoyed reading it. For me this
seemed to be one of the few books which teach a difficult subject through inquisition, and using programmed
concept for learning. After that book, Dr Harish Chandra Verma’s book on physics, CONCEPTS OF PHYSICS is
another such attempt, even though it is not directly in the dialogue form. I have thoroughly appreciated it. It
is clear that Dr Verma has spent considerable time in formulating the structure of the book, besides its contents.
I think he has been successful in this attempt. Dr Verma’s book has been divided into two parts because of the
size of the total manuscript. There have been several books on this subject, each one having its own flavour.
However, the present book is a totally different attempt to teach physics, and I am sure it will be extremely
useful to the undergraduate students. The exposition of each concept is extremely lucid. In carefully formatted
chapters, besides problems and short questions, a number of objective questions have also been included. This
book can certainly be extremely useful not only as a textbook, but also for preparation of various competitive
examinations.
Those who have followed Dr Verma’s scientific work always enjoyed the outstanding contributions he has
made in various research areas. He was an outstanding student of Physics Department of IIT Kanpur during
his academic career. An extremely methodical, sincere person as a student, he has devoted himself to the task
of educating young minds and inculcating scientific temper amongst them. The present venture in the form of
these two volumes is another attempt in that direction. I am sure that young minds who would like to learn
physics in an appropriate manner will find these volumes extremely useful.
I must heartily congratulate Dr Harish Chandra Verma for the magnificent job he has done.
Y R Waghmare
Professor of Physics
IIT Kanpur.
, PREFACE
Why a new book ?
Excellent books exist on physics at an introductory college level so why a new one ? Why so many books
exist at the same level, in the first place, and why each of them is highly appreciated ? It is because each of
these books has the privilege of having an author or authors who have experienced physics and have their own
method of communicating with the students. During my years as a physics teacher, I have developed a somewhat
different methodology of presenting physics to the students. Concepts of Physics is a translation of this
methodology into a textbook.
Prerequisites
The book presents a calculus-based physics course which makes free use of algebra, trigonometry and
co-ordinate geometry. The level of the latter three topics is quite simple and high school mathematics is sufficient.
Calculus is generally done at the introductory college level and I have assumed that the student is enrolled in
a concurrent first calculus course. The relevant portions of calculus have been discussed in Chapter 2 so that
the student may start using it from the beginning.
Almost no knowledge of physics is a prerequisite. I have attempted to start each topic from the zero level.
A receptive mind is all that is needed to use this book.
Basic philosophy of the book
The motto underlying the book is physics is enjoyable.
Being a description of the nature around us, physics is our best friend from the day of our existence. I have
extensively used this aspect of physics to introduce the physical principles starting with common day occurrences
and examples. The subject then appears to be friendly and enjoyable. I have taken care that numerical values
of different quantities used in problems correspond to real situations to further strengthen this approach.
Teaching and training
The basic aim of physics teaching has been to let the student know and understand the principles and
equations of physics and their applications in real life.
However, to be able to use these principles and equations correctly in a given physical situation, one needs
further training. A large number of questions and solved and unsolved problems are given for this purpose. Each
question or problem has a specific purpose. It may be there to bring out a subtle point which might have passed
unnoticed while doing the text portion. It may be a further elaboration of a concept developed in the text. It
may be there to make the student react when several concepts introduced in different chapters combine and
show up as a physical situation and so on. Such tools have been used to develop a culture: analyse the situation,
make a strategy to invoke correct principles and work it out.
Conventions
I have tried to use symbols, names, etc., which are popular nowadays. SI units have been consistently used
throughout the book. SI prefixes such as micro, milli, mega, etc., are used whenever they make the presentation
−6
more readable. Thus, 20 µF is preferred over 20 × 10 F. Co-ordinate sign convention is used in geometrical
optics. Special emphasis has been given to dimensions of physical quantities. Numerical values of physical
quantities have been mentioned with the units even in equations to maintain dimensional consistency.
I have tried my best to keep errors out of this book. I shall be grateful to the readers who point out any
errors and/or make other constructive suggestions.
H C Verma
[VOLUME 1]
H C VERMA, PhD
Retired Professor
Department of Physics
IIT, Kanpur
, Dedicated to
Indian Philosophy & Way of Life
of which
my parents were
an integral part
, FOREWORD
A few years ago I had an occasion to go through the book Calculus by L V Terasov. It unravels intricacies
of the subject through a dialogue between Teacher and Student. I thoroughly enjoyed reading it. For me this
seemed to be one of the few books which teach a difficult subject through inquisition, and using programmed
concept for learning. After that book, Dr Harish Chandra Verma’s book on physics, CONCEPTS OF PHYSICS is
another such attempt, even though it is not directly in the dialogue form. I have thoroughly appreciated it. It
is clear that Dr Verma has spent considerable time in formulating the structure of the book, besides its contents.
I think he has been successful in this attempt. Dr Verma’s book has been divided into two parts because of the
size of the total manuscript. There have been several books on this subject, each one having its own flavour.
However, the present book is a totally different attempt to teach physics, and I am sure it will be extremely
useful to the undergraduate students. The exposition of each concept is extremely lucid. In carefully formatted
chapters, besides problems and short questions, a number of objective questions have also been included. This
book can certainly be extremely useful not only as a textbook, but also for preparation of various competitive
examinations.
Those who have followed Dr Verma’s scientific work always enjoyed the outstanding contributions he has
made in various research areas. He was an outstanding student of Physics Department of IIT Kanpur during
his academic career. An extremely methodical, sincere person as a student, he has devoted himself to the task
of educating young minds and inculcating scientific temper amongst them. The present venture in the form of
these two volumes is another attempt in that direction. I am sure that young minds who would like to learn
physics in an appropriate manner will find these volumes extremely useful.
I must heartily congratulate Dr Harish Chandra Verma for the magnificent job he has done.
Y R Waghmare
Professor of Physics
IIT Kanpur.
, PREFACE
Why a new book ?
Excellent books exist on physics at an introductory college level so why a new one ? Why so many books
exist at the same level, in the first place, and why each of them is highly appreciated ? It is because each of
these books has the privilege of having an author or authors who have experienced physics and have their own
method of communicating with the students. During my years as a physics teacher, I have developed a somewhat
different methodology of presenting physics to the students. Concepts of Physics is a translation of this
methodology into a textbook.
Prerequisites
The book presents a calculus-based physics course which makes free use of algebra, trigonometry and
co-ordinate geometry. The level of the latter three topics is quite simple and high school mathematics is sufficient.
Calculus is generally done at the introductory college level and I have assumed that the student is enrolled in
a concurrent first calculus course. The relevant portions of calculus have been discussed in Chapter 2 so that
the student may start using it from the beginning.
Almost no knowledge of physics is a prerequisite. I have attempted to start each topic from the zero level.
A receptive mind is all that is needed to use this book.
Basic philosophy of the book
The motto underlying the book is physics is enjoyable.
Being a description of the nature around us, physics is our best friend from the day of our existence. I have
extensively used this aspect of physics to introduce the physical principles starting with common day occurrences
and examples. The subject then appears to be friendly and enjoyable. I have taken care that numerical values
of different quantities used in problems correspond to real situations to further strengthen this approach.
Teaching and training
The basic aim of physics teaching has been to let the student know and understand the principles and
equations of physics and their applications in real life.
However, to be able to use these principles and equations correctly in a given physical situation, one needs
further training. A large number of questions and solved and unsolved problems are given for this purpose. Each
question or problem has a specific purpose. It may be there to bring out a subtle point which might have passed
unnoticed while doing the text portion. It may be a further elaboration of a concept developed in the text. It
may be there to make the student react when several concepts introduced in different chapters combine and
show up as a physical situation and so on. Such tools have been used to develop a culture: analyse the situation,
make a strategy to invoke correct principles and work it out.
Conventions
I have tried to use symbols, names, etc., which are popular nowadays. SI units have been consistently used
throughout the book. SI prefixes such as micro, milli, mega, etc., are used whenever they make the presentation
−6
more readable. Thus, 20 µF is preferred over 20 × 10 F. Co-ordinate sign convention is used in geometrical
optics. Special emphasis has been given to dimensions of physical quantities. Numerical values of physical
quantities have been mentioned with the units even in equations to maintain dimensional consistency.
I have tried my best to keep errors out of this book. I shall be grateful to the readers who point out any
errors and/or make other constructive suggestions.
H C Verma
