physics ncert solutions class 11th

1.8 Some of the new-age technology which has transformed the present and has an immense potential to change the future are:

• Mobile phone technology ( 5G )
• Artificial Intelligence and Machine learning
• Biotechnology
• Nanotechnology
• 3D printing

1.7 The advancement of modern Science and industrial revolution always go hand in hand. The requirement of industrial revolution is always fulfilled by the new discoveries of modern science. Some of the examples are:

• Application of thermodynamics in steam engine had revolutionized the modern day transportation need
• Application of projectile motion, usage of iron and gun powder helped in development of cannons and guns. England and Western Europe conquered the rest of the world by these weapons
• The discovery of dynamite helped in mineral exploration

1.6 The argument (b) seems to be more logical and scientific.

1.5 Nobody has seen Air but we feel the presence of air at every moment. The constituents of air – oxygen, nitrogen etc. can be scientifically tested and proven. However the presence of ghosts or spirits cannot be scientifically proven, it exists in the imagination of superstitious people.

1.4 Some of the important factors that have hindered the advancement of Science in India:

• Poor infrastructure and fund
• Lack of co-ordination between Industry (consumers of scientific research) and the scientists (producers of scientific research)for the research topics
• Poor pay scale, uncertain future for the career growth, lack of motivation amongst young scientists
• Concentration of research labs in big cities deprives rural population

1.3 We are habituated with the false promises by the politicians during the elections and during their speeches; they say everything 'possible' to win votes. Science is the study of observation in a systematized manner. Scientists study these observations and formulate some laws, which can explain these observations irrespective of places and individuals.

Force of Gravity is universal, which is applicable for every object on earth as well as in moon also. Hence it proves that Science is the art of the soluble just as politics is the art of possible.

1.2 We all know that light travels in a straight line. When Huygens established his wave theory, it was a 'heresy'. Afterwards, it became a 'dogma' as reflection, refraction etc. could be successfully explained on the basis of wave theory.

Initially it was believed that light was only energy but when photoelectric effect was discovered, it was proposed that light had a particle nature also. This was treated as 'heresy'. Later on Einstein proved it by his quantum theory of light and it became a 'dogma'.

1.1 The world is full of surprises. There are so many things happening with everyone, sometimes it becomes difficult to comprehend by us. But all the things can be explained by basic laws of sciences. Thus the incomprehensible things around us become comprehensible when we look at from scientific viewpoint.