Class 11 Physics

Physical World


Part 3

Questions 11: Science, like any knowledge, can be put to good or bad use, depending on the user. Given below are some of the applications of science. Formulate your views on whether the particular application is good, bad or something that cannot be so clearly categorised:

  1. Mass vaccination against small pox to curb and finally eradicate this disease from the population. (This has already been successfully done in India).
  2. Television for eradication of illiteracy and for mass communication of news and ideas.
  3. Prenatal sex determination
  4. Computers for increase in work efficiency
  5. Putting artificial satellites into orbits around the Earth
  6. Development of nuclear weapons
  7. Development of new and powerful techniques of chemical and biological warfare).
  8. Purification of water for drinking
  9. Plastic surgery
  10. Cloning

Answer: Good: a, b, d, e, h, i,

Bad: c, f, g

Either Good or Bad: (i) Cloning: It depends on how we use this technology. Cloning can be used for growing artificial organs so that many needy patients can get timely transplant. Cloning can also be used for creating monsters to destroy the humankind.

Questions 12: India has had a long and unbroken tradition of great scholarship — in mathematics, astronomy, linguistics, logic and ethics. Yet, in parallel with this, several superstitious and obscurantistic attitudes and practices flourished in our society and unfortunately continue even today — among many educated people too. How will you use your knowledge of science to develop strategies to counter these attitudes?

Answer: Knowledge of science should be used to increase public awareness. For example; many people still give preference to a male child over a girl child because of certain prejudices. Moreover, many people blame a woman if she fails to bear a male child. This state of ignorance can be reduced by suitable use of scientific knowledge to increase awareness about the issue. Kerala has the highest literacy level and also has the best gender ratio in the country. This shows the role of literacy in removing age old prejudices and biases.

Questions 13: Though the law gives women equal status in India, many people hold unscientific views on a woman’s innate nature, capacity and intelligence, and in practice give them a secondary status and role. Demolish this view using scientific arguments, and by quoting examples of great women in science and other spheres; and persuade yourself and others that, given equal opportunity, women are on par with men.

Answer: Examples of women achievers can be taken from every walk of life to illustrate this point. We can take examples of Kalpana Chawla, Indira Gandhi, Marie Curie, etc. The latest example is of Mission Mars from India in which the team was mainly comprised of women scientists.

Questions 14: “It is more important to have beauty in the equations of physics than to have them agree with experiments”. The great British physicist P. A. M. Dirac held this view. Criticize this statement. Look out for some equations and results in this book which strike you as beautiful.

Answer: For majority of people, criticizing this statement can be easy because most of the people find physics as a dry and boring subject. But if you will read the book A Brief History of Time by Stephen Hawking, you will agree with this statement. Once a student begins to find beauty in studying a subject he/she develops a real interest in that subject.

Questions 15: Though the statement quoted above may be disputed, most physicists do have a feeling that the great laws of physics are at once simple and beautiful. Some of the notable physicists, besides Dirac, who have articulated this feeling, are: Einstein, Bohr, Heisenberg, Chandrasekhar and Feynman. You are urged to make special efforts to get access to the general books and writings by these and other great masters of physics. (See the Bibliography at the end of this book.) Their writings are truly inspiring!

Answer: Do it yourself

Questions 16: Textbooks on science may give you a wrong impression that studying science is dry and all too serious and that scientists are absent-minded introverts who never laugh or grin. This image of science and scientists is patently false. Scientists, like any other group of humans, have their share of humorists, and many have led their lives with a great sense of fun and adventure, even as they seriously pursued their scientific work. Two great physicists of this genre are Gamow and Feynman. You will enjoy reading their books listed in the Bibliography

Answer: Do it yourself