Class 11 Physics Chapter 1 – Physical World
What is Physics? Introduction to Physics
[Watch Video for Understanding More with Explanation and Examples]
Physics is one of the basic disciplines in the category of Natural Sciences. Physics is broadly described as the study of nature and natural phenomena or it is the study of nature and its laws.
It is not easy to understand nature or natural phenomena and laws related to it. Careful observation could give some idea about it, but not completely.
Scientists discover many laws of nature based on observations at that time. Laws in physics are not fixed, finding new rules may make old rules inapplicable or wrong or may open up possibilities for new rules.
Two principal thrusts in physics related to understanding laws of nature, they are unification and reduction.
In unification the attempt is to explain diverse physical phenomena in terms of a few concepts and laws. The effort is to see the physical world as manifestation of some universal laws in different domains and conditions. For example: law of gravitation is used to explain different phenomena like falling of body downwards, motion of moon around earth, motion of planets around sun, etc. Another example is electricity, magnetism, light, are explained by basic laws of electromagnetism.
Reduction / reductionism is an effort to solve big and more complex problems by breaking it into simpler parts. For example, temperature of a system is explained by reducing it to kinetic energy of molecules of the system.