The word ‘science’ has its root in the Latin verb scientia, meaning “to know”. In Tamil language, it is ‘அறிவியல்’ (Ariviyal) meaning ‘knowing the truth’. The human mind is always curious to know and understand different phenomena like the bright celestial objects in nature, cyclic changes in the seasons, occurrence of rainbow, etc. The inquisitive mind looks for meaningful patterns and relations in such phenomena. Today’s modern science and technology is an offshoot of the understanding of nature. Science is the systematic organization of knowledge gained through observation, experimentation and logical reasoning. The knowledge of science dealing with non-living things is physical science (Physics and Chemistry), and that dealing with living things is biological science (Botany, Zoology etc.).
Curiosity-driven observations of natural happenings was the origin of science. The word ‘science’ was coined only in the 19th century. Natural philosophy was the earlier name given to science, when ancient civilization knew and practised astronomy, chemistry, human physiology and agriculture. Oral communication was the mode of conveying knowledge when writing systems were not yet developed. One of the oldest forerunners of scientific advancements, from astronomy to medicine, were the Egyptians. Scientific and mathematical excellence in India dates back to prehistoric human activity in the Indus Valley Civilization (3300 - 1300 BCE).
The scientific method is a step-by-step approach in studying natural phenomena and establishing laws which govern these phenomena. Any scientific method involves the following general features.
i. Controlled experimentation
ii. Qualitative and quantitative reasoning
iii. Mathematical modeling
iv. Prediction and verification or falsification of theories
Consider a metalic rod being heated. When one end of the rod is heated, heat is felt at the other end. The following questions can be asked on this observation
i. What happens within the rod when it is heated?
ii. How does the heat reach the other end?
iii. Is this effect true for all materials?
iv. If heat flows through the material, is it possible to visualize heat?
The process of finding the answers to these queries is scientific investigation.
The basic phenomenon of heat is discussed in unit 8.