Physical World Important Questions

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Questions:

1 Marks

5 x 1 = 5

Give an example of achievement in unification.

In macroscopic level of Physics, gravitational force is dominant as compared to electromagnetic force, why?

Give one major discovery resulted due to basic laws of electricity and magnetism.

Quantitative measurement plays major role in Physics, why?

Why do we call Physics an exact Science?

Generic 2

5 x 2 = 10

Name the force which builds the universe.

Name the contribution made by the following physicists:
(a) S.N. Bose
(b) J. C. Maxwell
(c) Paul Dirac
(d) Max Planck

Name three conservation laws from nature.

The industrial revolution in England and Western Europe more than two centuries ago was triggered by some key scientific and technological advances. What were these advances?

10.

Every great physical theory starts as a heresy and ends as a dogma. Give some examples from the history of science, of the validity of this incisive remark.

Generic 3

5 x 3 = 15

11.

Deepa's uncle was surprised to see the fast changes in the world. He is not so educated. He asked Deepa to tell him the names and qualities of some persons who have contributed for bringing the rapid changes in the world. Deepa who is science graduate explained about some discoveries and the names of scientist who have done a marvellous work in physics.
(i) Why Deepa's uncle was so curious to know things changed recently?
(ii) What values are displayed by Deepa?
(iii) Name at least three Indian scientists.

12.

Physics has a very limited scope and only in practice of a few blessed ones. Do you agree?

13.

How is the fate of society linked to the developments in physics?

14.

The shells of crabs found around a particular coastal location in Japan seem mostly to resemble the legendary face of a Samurai. Given below are two explanations of this observed fact. Which of these strikes you as a scientific explanation?
(a) A tragic sea accident several centuries ago drowned a young Samurai. As a tribute to his bravery, nature through its inscrutable ways immortalized his face by imprinting it on the crab shells in that area.
(b) After the sea tragedy, fishermen in that area, in a gesture of honour to their dead hero, let free any crab shell caught by them which accidentally had a shape resembling the face of a Samurai. Consequently, the particular shape of the crab shell survived longer and therefore in course of time the shape was genetically propagated. This is an example of evolution by artificial selection.
[Note: This interesting illustration taken from Carl Sagan's 'The Cosmos' highlights the fact that often strange and inexplicable facts which on the first sight appear 'supernatural' actually turn out to have simple scientific explanations. Try to think out other examples of this kind].

15.

Write in about 1000 words, a fiction piece based on your speculation on the science and technology of the twenty second century.

Generic 5

1 x 5 = 5

16.

Science, like any knowledge, can be put to good or bad use, depending on the user. Given below are some of the application of science. Formulate your views on whether the particular application is good, bad or something that cannot be so clearly categorized.
(i) Mass vaccination against small pox to curb and finally eradicate this disease from the population.
(ii) Television for eradication of illiteracy and for mass communication for news and ideas.
(iii) Prenatal sex determination.
(iv) Computers for increase in work efficiency.
(v) Putting artificial satellites around the earth.
(vi) Development of nuclear weapons.
(vii) Development of new and powerful techniques of chemical and biological warfare.
(viii) Purification of water for drinking.
(ix) Plastic surgery.
(x) Cloning.

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Answers Key:

1 Marks

5 x 1 = 5

()
Unified celestial and terrestrial mechanics showed that the same laws of motion and the law gravitation apply to both the domains.

()
Because, matter as a whole is electrically neutral due to presence of both negative and positive charge in equal quantity.

()
Wireless communication technology was a major discovery due to laws of electricity and magnetism.

()
Quantitative measurement plays major role in Physics, because all the laws of nature are better expressed in the form of mathematical equation.

()
Most of measurement in physics are made with high precise and accuracy, so it is called exact Science.

Generic 2

5 x 2 = 10

Quark-Quark force caused by the exchange of particles called' gluons' is the basic force.

(a) S. N. Bose Quantum Statistics
(b) J. C. Maxwell - Electromagnetic Theory
(c) Paul Dirac - Relativistic Theory of Electron
(d) Max Planck - Quantum Theory

Three important laws of conservation from nature are:
1. Law of conservation of energy.
2. Law of conservation of momentum.
3. Law of conservation of angular momentum.

The industrial revolution in England and Western Europe more than two centuries ago was triggered by some key scientific and technological advances.
A few of which are given below
(i) Discovery of electricity
(ii) Invention of powerloom, safety lamp, cotton gin, steam engine, etc.

10.

The statement is true, e.g. in ancient times, Ptolemy postulated that earth is stationary and all the heavenly bodies like sun, stars, planets etc., revolve around earth. Later, an Italian scientist, Galileo postulated that sun is stationary and earth along with other planets is revolving around the sun.
Galileo was punished by the authorities for spreading wrong concepts. However, later on. Newton and Kepler supported Galileo's theory and now it is no more than a dogma.

Generic 3

5 x 3 = 15

11.

(I) Deepa's uncle is not educated and he is comparing the period of his early life when he could no have communication system, computers, LED's and LCDs. etc. with his present period.
(ii) Sympathy, helping, awareness and intelligence are the values displayed by Deepa.
(iii) Names of Indian Scientists are:
(a) H.J. Bhaba
(b) S.N. Bose
(c) CV. Raman
(d) J.C Bose

12.

No, it is not true. Physics has unlimited scope and its conceptual base can be noticed in immense number of activities/ fields. Can a cricket or a hockey player say that physics has nothing to do with his game? No, he is using collision phenomenon every second of his game along with Newton's laws of motion. Can you say that you walk without physics, talk without physics, eat without physics and so on, all that need friction. A musician uses physics. Physics is applied in every walk of life. Therefore we can not say that physics is noticed only in the practice of few blessed ones.

13.

The end of 20th century is a witness of the intricate relation between science and society. If one can say that it has entered the nerves of the society, it will not be an exaggeration. Even the marriages are being fixed on internet and celebrated in aeroplanes. Think of discos. You can make images of criminals by computers apart from host of other activities like reservation, animation, designing, printing etc. These effects on society are in addition to the ones which revolutionized and societies by mechanical revolution of first half of the 20th century like X-rays, nuclear energy, wireless, satelite, electronics, computer and robots

14.

The explanation given in option (b) strikes as a scientific explanation.

15.

Imagine you along with your friends are in a spaceship which is moving towards Mars. The body of the speceship is made of a specially designed matter which become more harder as its temperature increases. nuclear power plants in spaceship.
Two of them work alternatively and third is for emergency. The speed of the spaceship is very high and all of you are very happy. The energy produced in power plants are converted into electric energy which runs the motors of the spaceship.
You along with your friends reach safely on Mars, collects data, takes photographs and then returns to the Earth. In return journey is working and due to overheating. its efficiency is decreasing continuously.
You and your friends try to reduce the temperature of the plant and try to repair the fuse of the other power plants.
Finally, fuse of one other plant is repaired and start to work before the first plant crosses the danger limit of an excess of temperature. Finally, you and your friends return safely on Earth.

Generic 5

1 x 5 = 5

16.

(i) Mass vaccination is good as, it is used to make the socity free from the diseases like small pox.
(ii) Television for eradication of illiteracy and for mass communication of news and ideas is good as, it is a medium which is easily within the reach of common man and also they are very habitual to it.
(iii) Prenatal sex determination is bad because people are misusing it. Some of the people after determination of sex of child, think to abort. They do it especially with girl child.
(iv) Computer for increase in work efficiency is good as using the computer, a man can do much more work with greater efficiency and accuracy.
(v) Putting artificial satellite into orbits around the Earth is good for development as these satellites serve many purpose like remote sensing, weather foresting.
(vi) Development of nuclear weapons is bad as they can be used in mass destruction.
(vii) Development of new and powerful tool of chemical and biological warfare are bad, as they can also be used for mass destruction.
(viii) Purification of water for drinking purpose is good as we can save ourself from the diseases which we can have due to drinking of the water.
(ix) Plastic surgery is good as with the help of it a man or women can remove the skin defects occurring due to accident or some other reasons. It has some bad effects too but they are not very considerable.
(x) Cloning is good as far as animals are concerned. With the help of it, we can develop some species of animals which can be used to serve some specific purpose. But it is not good for human beings.