How to study Physics in 11th and 12th class
Importance of Physics as a subject of study
Physics is the most fundamental science. Knowledge of physics forms the base for all the branches of science and engineering. So for a science student it is very important to gain a basic knowledge of physics. That is why physics is a compulsory subject for science students in 11th and 12th class in India.
What is Physics?
It is very easy to define chemistry or biology. Chemistry is the science that studies material transformations which occur in nature. Biology is the science that studies about Life and Processes related to Life. Chemistry and Biology have therefore a very well defined area of interest.
But if we consider physics, we see, in physics we study about motion, force, energy, light, heat, gravitation, electricity, atoms, nucleus of atoms, molecules, planets, stars, universe….etc. the list is endless. Thus we see, in physics we study about atoms, nucleus, electrons, protons, neutrons, quarks… at one extreme, and we study about galaxies and universe at the other extreme. And in physics we also study about everything that comes in between these two extremes. So what is left? Nothing frankly! So we can say in physics we study about everything that is part of nature. That is why it is very difficult to define the scope of physics. But still if we like to define physics we can say “ Physics is that branch of science in which we try to understand the rules by which the nature works at every level of its existence (from microscopic to the mega macroscopic)”.
People think that by studying science in general, and physics in particular, they will be able to answer all the WHY?, WHAT? Or HOW? questions. But mind you, that is not the aim of physics. Aim of physics is to understand the rules behind the working of nature. Yes, by gaining such understanding you will surely answer some WHY?, WHAT? or HOW? questions, but some questions may remain unanswered. For example, everybody knows that some particles(like electrons) posses a property called Electrical Charge. But why do they possess electric charge? Why there are two kinds of charges in nature whereas there is only one kind of mass? Why electrical force can be both attractive or repulsive whereas gravitational force is always attractive? There is no answer to these questions. These are facts. Yes, in future with the expansion in our knowledge about the rules of nature, we may answer some of these questions but today we can’t. And even if we don’t know the answers to these “why?” questions, then also the knowledges that we gained from the above facts are helpful to human race. The entire branch of electrical engineering is based on the fact that Electric Charge exists which can flow through a conducting wire to give Electric Current. Although we don’t know why electric charge exists in the first place.