Chapter 1 Physical World Solutions
Question - 1 : - Some of the most profound statements on the nature of science have come from Albert Einstein, one of the greatest scientists of all time. What do you think did Einstein mean when he said : “The most incomprehensible thing about the world is that it is comprehensible” ?
Answer - 1 : -
Probably Einstein meant that the science can marvellously explain through simple theories of the various natural phenomena which become comprehensible to us. In fact it is unthinkable that complex natural phenomenon can be so comprehensible with scientific analysis which for an ordinary person is incomprehensible.
Question - 2 : - “Every.great physical theory starts as a heresy and ends as a dogma”. Give some examples from the history of science d(f the validity of this incisive remark.
Answer - 2 : -
Heresy is .something which is not established, whereas dogma means established view e.g. there was a heresy that inertia of a body depended upon its energy. But Einstein gave a simple equation E = me2, relation between mass and energy. This is a dogma in physics. Another heresy is that in ancient times Ptolemy postulated that the earth is stationary and entire heavenly bodies move around. But the dogma is that earth itself moves around the Sun.
Question - 3 : - “Politics is the art of the possible”. Similarly, “Science is the art of the soluble”. Explain this beautiful aphorism on the nature and practice of science.
Answer - 3 : -
Politicians would make anything possible by their sheer words. But majority of things may not be possible in practice. Whereas science can make us understand the phenomena around us. e.g. total solar eclipse shows an interesting aspect of solar temperature. Its chromosphere temperature is about 6000 K. But as we go out towards the rim, it first falls and then suddenly rises to a million kelvin or higher. Science is concerned to provide an explanation or find a solution to this riddle. The repeated practice of science allows us to hypothesis, make calculations, experiment with these and then predict the possible solution.
Question - 4 : - Though India now has large base in science and technology, which is fast expanding, it is still a long way from i. realizing its potential of becoming a world leader in science. Name some important factors, which in your view hindered the advancement of science in India.
Answer - 4 : -
- Lack of education
- Lack of scientific attitude in the students
- Money plays the key role
- Lack of practice etc.
Question - 5 : - No physicist has ever “seen” an atom. Yet, all physicists believe in the existence of atoms. An intelligent but superstitious man advances this analogy to argue that ‘ghosts’ exist even though no one has ‘seen’ one. How will you refute his argument ?
Answer - 5 : -
It is simply a superstition that ghosts exist. There is not even a single authentic evidence that ghosts exist. There are may examples to prove this fact. Atomic power plants, atomic bomb, atomic clocks etc. exist because atoms exist in nature. Thus there is no co-relation between two parts of the statement.
Question - 6 : - The shells of crabs found around a particular 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 Samurhi. As a tribute to this bravery, nature through its inscrutable ways immortalized his face by imprinting in on the crab shells in that area.
(b) After the sea tragedy, fishermen in the 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.
Answer - 6 : -
Statement (b) is scientific.
Question - 7 : - The industrial revolution in England and Western Europe more that two centuries ago was triggered by some key scientific and technological advances. What were there advances ?
Answer - 7 : -
Prior to 1750 AD when Industrial revolution happened, simple tools and machines were used. But industrial revolution brought new machinery. Some of the outstanding contributions of the industrial revolution were
- Steam engine
- Blast furnace which converts low grade iron into steel
- Cotton gin which separates the seed from cotton three hundred times faster than by hand etc.
Question - 8 : - It is often said that the world is witnessing now a second industrial revolution, which will transform the society as radically as did the first. List some key contemporary areas of science and technology, which are responsible for this revolution.
Answer - 8 : -
The key areas which are responsible for revolution are
- Super fast computers
- Biotechnology
- Development of super conducting materials at room temperature etc.
Question - 9 : - Write in about 1000 words a fiction piece based on your speculation on the science and technology of the twenty- second century.
Answer - 9 : -
Let us imagine a spaceship moving towards a distant star, 500 light years away. Suppose this is propelled by current fed into the electric motor consisting of super conducting wires. In space, suppose there is a particular region which has such a (high temperature that destroys the super conducting property of the electric wires of the motor. At this stage, another spaceship filled with matter and anti-matter comes to the rescue of the first ship, and the first ship continues its onward journey.
Question - 10 : - Attempt to formulate your ‘moral’ views on the practice of science. Imagine yourself stumbling upon a discovery, which has great academic interest but is certain to have nothing but dangerous consequences for the human society. How, if at all, will you resolve your dilemma ?
Answer - 10 : -
Scientific discovery reveals a truth of nature. Therefore any discovery, good or bad for mankind must be made public. The discovery which appears to be dangerous today may become useful to the mankind later on. In order to avoid the misuse of scientific technology, we must built up a strong public opinion. Thus scientists should do two things
- To discover truth and
- To prevent its misuse.