Why yet another course in physics?

Answer to this question is vital to justify yet another course (book) on the subject, specially when, thereexists brilliant books on the shelves, successfully meeting the requirement of schools. Understandably, each of these books /courses has been developed through a rigorous process, conforming to a very high level of standards prescribed by state educationboards. Why then yet another course (book)? Matter of fact, this question had been uppermost in my mind before Iundertook the commitment to take up this project. A good part of the reason lies in the basic nature of creative urge involved inwriting and shaping a book. Besides, as an author, I had the strong conviction like others that a subject matter can always be treatedin yet another way, which may be a shade different and may be a shade better than earlier efforts. This belief probably clinched myinitiation into this project. Further :

1 : It is no wonder that books have been published regularly - many of which have contributed significantlyto the understanding of the nature and natural events. Also, there is no doubt that there has been a generalimprovement in the breath and depth of the material and style of presentation in the new books, leading to a better appreciationamong the readers about the powerful theories, propounded by great human minds of all time. However, one book differs to other incontent, treatment, emphasis and presentation. This book is different on this count.

2 : Fundamental laws of physics are simple in construct. Take the example of Newton’s second law : $\mathbf{F}=m\mathbf{a}$ . This could not have been simpler. Yet, it takes great deal ofinsight and practice to get to the best of mechanics – a branch of physics, which is largely described by this simpleconstruct. The simplicity of fundamental laws, matter of fact, is one of the greatest wonders of nature. Difficulty arises, mostly,from the complexity of the context of natural phenomena, which are generally culmination of a series of smaller events interwoven invarious ways. The challenge here is to resolve complex natural phenomena into simpler components, which can then be subjected tothe theories of physics. Resolution of complex natural phenomena into simpler components is an important consideration in physics. Thisbook keeps this aspect of physics central to its treatment of the subject matter.

3 : Overwhelming and awesome reach of theories in physics, inadvertently, introduces a sense of finalityand there is a tendency to take an approach towards the study of physics, which is serene and cautious – short of‘do_not_fool_around’ kind of approach. This book takes calculated risk to play around with the hypotheses and theories to initiatereaders to think deeper and appreciate physics with all its nuances. The book is structured and developed from the perspectiveof inquisitive young minds and not from the perspective of a matured mind, tending to accept theory at its face value. Thisshift in approach is the cornerstone of subject treatment in this book.

4 : Mathematics fine tunes physics laws and gives it a quantitative stature. Most of the extension of physicallaws into the realm of application is possible with the intelligent use of mathematical tools at our disposal. Further, adaptation ofphysical laws in mathematical form is concise and accurate. Consider the magnetic force on a moving charge given by :

$\mathbf{F}=q(\mathbf{v}X\mathbf{B})$

The mathematical expression is complete and accurate. It tells us about both magnitude and direction of themagnetic force on the moving charge. Matter of fact, direction of force in relation to velocity of charge andmagnetic field is difficult to predict without this formula. Either, we rely on additional rules like Fleming’s left hand ruleor interpret the vector quantities on the right hand side of the equation in accordance with rules concerning cross product of twovectors. The choice of mathematical vector interpretation is found to avoid confusion as Fleming’s rule requires that we memorizedirection of each of the vectors by a specific finger from the set of three fingers stretched in mutually perpendicular directions.There is great deal of uncertainty involved. You may forget to remember the correct hand (left or right), correct fingers (first, middle or thumb)and what each of themrepresents. On the other hand, vector interpretation has no element to memorize to predict the direction of magnetic force! Such is thepower of mathematical notation of physical law.

In this sense, mathematics is a powerful tool and preferred language of expression in physics. Separate modulesare devoted to describe mathematics relevant to physics in order to prime readers before these tools are used in the context ofphysics.

5 : The fundamental laws/ theories of physics are universal and result of great insight into the realm ofphysical proceedings. New constructs and principles are difficult to come by. The last defining moment in physics was development ofthe quantum physics by Erwin Schrodinger and Werner Heisenberg in the year 1925-26. Since then, there had been advancement in theparticle physics and electronics, but no further aggregation of new theories of fundamental nature. Physics, however, has progressed agreat deal in its application to other spheres of science, including engineering, medicine and information technology. Thisbook assigns due emphasis to this aspect of applied physics.

6 : Various Boards of State Education prescribe well thought out framework and standards for development of physics text book for classroom teaching. This bookemphasizes these standards and goals set up by the Boards.