01 भौतिक दुनिया
अभ्यास करें
Question:
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:
Albert Einstein was suggesting that it is remarkable that the world around us can be understood through the use of scientific inquiry. He was emphasizing the power of science to explain the complexities of the universe and the fact that humans can comprehend the laws of nature. He was acknowledging the incredible power of science to provide insight into the workings of the world, and in doing so, to provide a greater understanding of our place in it.
Question:
“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.
Answer:
Example 1: Newton’s Laws of Motion were once considered a heresy, but are now accepted as a scientific dogma.
Example 2: The theory of evolution by natural selection, proposed by Charles Darwin, was once considered a heresy, but is now accepted as a scientific dogma.
Example 3: The Big Bang Theory was once considered a heresy, but is now accepted as a scientific dogma.
Question:
“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:
This aphorism is a comparison between politics and science. It suggests that, just as politics is about finding the most achievable solutions to problems, science is about finding solutions to problems that can be solved. In other words, science is about finding solutions that are not just possible, but also feasible. This means that science is a process of experimentation and analysis that is focused on discovering the most practical and effective solutions to problems. The aim of science is to solve problems, not just to make them more manageable. This aphorism captures the essence of the scientific method: the process of identifying a problem, developing hypotheses, testing those hypotheses, and arriving at a solution. Science is an iterative process that requires creativity, ingenuity, and a willingness to challenge accepted wisdom in order to find solutions that are both achievable and practical.
Question:
Though India now has a large base in science and technology, which is fast expanding, it is still a long way from realising its potential of becoming a world leader in science. Name some important factors, which in your view have hindered the advancement of science in India.
Answer:
- Lack of adequate funding for research and development in the field of science.
- Poor quality of scientific infrastructure.
- Low levels of awareness about the importance of science and its applications among the general public.
- Insufficient number of trained scientists and engineers.
- Lack of incentives for scientists and engineers to pursue research and development.
- Inadequate number of scientific and technological institutions.
- Difficulty in accessing the latest scientific and technological knowledge.
- Poor quality of education in the field of science.
- Unavailability of modern scientific equipment and resources.
- Lack of government policies and initiatives to promote science and technology.
Question:
No physicist has ever “seen” an electron. Yet, all physicists believe in the existence of electrons. 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:
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Point out that the analogy being used is flawed, as electrons have been indirectly observed through the effects of their presence, such as the deflection of cathode rays in a vacuum tube.
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Explain that, unlike electrons, there is no evidence that ghosts exist, either direct or indirect.
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Emphasize that scientific knowledge is based on evidence, and that without any evidence to support the existence of ghosts, it is not possible to conclude that they exist.
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Highlight the difference between superstition and science, and explain that while superstition is based on faith, science is based on facts.
Question:
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 immortalised 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.
Answer:
Answer: (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.
Question:
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?
Answer:
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Analyze the question: The question is asking what advances triggered the industrial revolution in England and Western Europe.
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Research the answer: The advances that triggered the industrial revolution in England and Western Europe include the invention of the steam engine, the development of the spinning jenny and other mechanized textile production machines, the invention of the water frame and other mechanized production machines for the production of nails, and the invention of the power loom and other weaving machines. Additionally, advances in iron production, such as the invention of the blast furnace, and advances in transportation, such as the development of the railway, were key components of the industrial revolution.
Question:
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:
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Robotics: Robotics is a key area of science and technology responsible for the second industrial revolution, as robots are increasingly being used in factories and other industries to automate processes, reduce costs, and increase efficiency.
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Artificial Intelligence: Artificial Intelligence (AI) is another key area of science and technology responsible for the second industrial revolution. AI is being used to develop smarter machines that can learn from past experiences and make decisions based on the data they have received.
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Internet of Things: The Internet of Things (IoT) is a network of connected devices that allow for the collection and sharing of data. This technology is enabling businesses to optimize their operations and make decisions based on real-time data.
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Big Data: Big data is a large set of data that can be analyzed to gain insights into trends and patterns. This technology is being used to improve decision-making and operations in businesses.
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3D Printing: 3D printing is a technology that allows for the creation of three-dimensional objects using digital designs. This technology is being used to create products faster and more efficiently, and it is revolutionizing the manufacturing industry.
Question:
Write in about 1000 words a fiction piece based on your speculation on the science and technology of the twenty-second century.
Answer:
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Begin by brainstorming ideas for the story. Think of the world in the twenty-second century, what kind of technology will exist? What kind of scientific advancements will be made? Consider the implications of these advancements and how they might affect everyday life.
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Choose a setting for the story. This can be a specific location or a more general setting. Consider the atmosphere of the setting and the people that inhabit it.
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Create characters for the story. Decide on the main character and any supporting characters. Think about their relationships and how they interact with each other.
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Develop a plot for the story. Consider the main conflict and how it will be resolved. Think of any subplots and how they will be resolved as well.
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Write the story. Begin with an introduction to the setting and characters. Then, progress the story through the main conflict and any subplots. Make sure to include details about the science and technology of the twenty-second century and how it affects the characters and their actions.
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Edit the story. Read through the story and make any necessary changes. Make sure that the story flows logically and is free of any grammar or spelling errors.
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Publish the story. Find a platform to publish the story, such as a blog or website. Share the story with friends and family and ask for feedback.
Question:
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 will you resolve your dilemma ?
Answer:
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First, I would consider the potential consequences of my discovery and determine whether they outweigh the potential benefits. If the consequences are too severe, I would refrain from pursuing the discovery further.
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If the consequences are not too severe, I would consider what ethical guidelines exist in my field of study and determine whether pursuing the discovery would violate any of them. If so, I would again refrain from pursuing the discovery further.
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If the discovery does not violate any ethical guidelines, I would consider the risk of the consequences and determine whether the potential benefit is worth taking the risk. If the risk is too great, I would again refrain from pursuing the discovery further.
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If the risk is acceptable, I would consider the potential impact of my discovery. If I believe that the discovery could have a positive impact on humanity, I would pursue the discovery further, taking measures to mitigate any potential risks.
Question:
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 :
(a) Mass vaccination against small pox to curb and finally eradicate this disease from the population. (This has already been successfully done in India).
(b) Television for eradication of illiteracy and for mass communication of news and ideas.
(c) Prenatal sex determination
(d) Computers for increase in work efficiency
(e) Putting artificial satellites into orbits around the Earth
(f ) Development of nuclear weapons
(g) Development of new and powerful techniques of chemical and biological warfare).
(h) Purification of water for drinking
(i) Plastic surgery
(j ) Cloning
Answer:
(a) Mass vaccination against small pox to curb and finally eradicate this disease from the population. (This has already been successfully done in India). - Good
(b) Television for eradication of illiteracy and for mass communication of news and ideas. - Good
(c) Prenatal sex determination - Bad
(d) Computers for increase in work efficiency - Good
(e) Putting artificial satellites into orbits around the Earth - Good
(f ) Development of nuclear weapons - Bad
(g) Development of new and powerful techniques of chemical and biological warfare) - Bad
(h) Purification of water for drinking - Good
(i) Plastic surgery - Cannot be clearly categorised
(j ) Cloning - Cannot be clearly categorised
Question:
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:
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Identify the superstitious and obscurantistic attitudes and practices that are prevalent in Indian society.
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Research and gather evidence from scientific sources that debunk these attitudes and practices.
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Develop a strategy to communicate the scientific evidence in a way that is accessible and understandable to the general public.
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Utilize media and other channels to spread awareness about the scientific evidence and its implications.
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Engage in dialogue with people who hold superstitious and obscurantistic beliefs to help them understand the scientific evidence.
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Encourage people to think critically and evaluate their beliefs in light of the scientific evidence.
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Create opportunities for people to learn more about scientific concepts and how they can be used to counter superstitious and obscurantistic attitudes.
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Monitor the progress of the strategies and evaluate their effectiveness.
Question:
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:
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Begin by acknowledging the fact that many people still hold unscientific views on a woman’s innate nature, capacity and intelligence, and in practice give them a secondary status and role.
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Provide scientific evidence that women are in fact equal to men in terms of innate nature, capacity and intelligence. This could include citing research studies that show no significant differences in cognitive abilities between men and women.
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Highlight the achievements of great women in science and other spheres to demonstrate that women are capable of achieving anything they set their minds to, given equal opportunity.
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Explain the importance of providing equal opportunity for women, and how it can help them reach their full potential.
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Use persuasive language to encourage yourself and others to believe that women are on par with men, and that they should be given equal opportunities to succeed.
Question:
“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 other equations and results , which strike you beautiful.
Answer:
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P.A.M. Dirac’s statement can be seen as an opinion, as beauty is subjective and therefore difficult to measure.
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However, it is also important to consider that equations that are aesthetically pleasing often yield accurate results. For example, Euler’s identity, which states that e^(iπ) + 1 = 0, is considered by many to be beautiful, and it is also a mathematically accurate equation.
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Furthermore, it is important to consider the practical implications of equations and results. While a result may be aesthetically pleasing, it may not be applicable in real-world scenarios. For example, the Schwarzschild solution to the Einstein field equations is considered to be a beautiful result, but it is only applicable in the context of black holes.
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Ultimately, it is important to consider both the aesthetic and practical implications of equations and results. While beauty may be important, it should not be the only factor considered when evaluating equations and results.
Question:
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:
- Most physicists have a feeling that the great laws of physics are both simple and beautiful.
- Several notable physicists have expressed this feeling, including Dirac, Einstein, Bohr, Heisenberg, Chandrasekhar, and Feynman.
- Readers are encouraged to access the general books and writings of these great masters of physics.
- The bibliography at the end of the book can provide guidance in accessing these writings.
- These writings are inspiring.
Question:
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 anyother 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:
- Textbooks on science may give the false impression that studying science is dull and that scientists are introverts who never laugh or smile.
- However, this image of science and scientists is not accurate.
- Just like all other groups of people, scientists have funny people among them and many have had a lot of fun and excitement while doing their scientific work.
- Two famous physicists who exemplify this are Gamow and Feynman.
- You can learn more about them by reading the books listed in the Bibliography.
जेईई अध्ययन सामग्री (भौतिकी)
01 भौतिक दुनिया
02 इकाइयां और मापन
03 सीधी रेखा में गति
एक विमान में 04 गति
गति के 05 नियम
06 कार्य, ऊर्जा और शक्ति
07 कणों की प्रणाली और घूर्णी गति
08 गुरुत्वाकर्षण
09 ठोस के यांत्रिक गुण
तरल पदार्थ के 10 यांत्रिक गुण
पदार्थ के 11 ऊष्मीय गुण
12 ऊष्मप्रवैगिकी
13 काइनेटिक थ्योरी
14 दोलन
15 तरंग