What is Physics ?
Physics is a basic discipline in the category of Natural Science. The word “ Physics came from the Greek word ‘Fusis’ meaning nature.
Its Sanskrit equivalent is “Bhautiki that is used to refer to the study of the physical world. Hence Physics is the branch of science which
is devoted to the study of nature and natural phenomena. Thus physics is the most basic of all sciences.
In the study of Physics, there are two principle thrusts: Unification and Reductionism.
Unification means attempting to explain diverse physical phenomenon in terms of a few concepts and laws.
For example – the same law of gravitation is given by Newton accounts for
i. fall of an apple
ii. Motion of satellites around the planets
iii. Motion of planets around the sun.
Similarly basic laws of electromagnetism explain all the electric and magnetic phenomena.
Reductionism means attempting to derive the properties of a bigger, more complex system from the properties of its constituent simpler parts.
For example- the subjects of thermodynamics deals with bulk in terms of macroscopic quantities like temperature, internal energy, entropy etc.
The later developments of kinetic theory and statistical mechanics interpreted these quantities in terms of the properties of the molecular
constituents of the bulk systems.
For example temperature of the bulk system was related to the average kinetic energy of the molecules of the system.