If you want to learn physics well, you should not only learn physics well, but also learn other courses such as mathematics, chemistry, Chinese and history, that is to say, learn what you want. In fact, in school, the students we meet who study well do well in all subjects, while the students who study poorly do poorly in all subjects, which is basically the case. In addition to the innate factors of small probability, there is indeed a learning method problem here.
Who doesn't want to be a good student, but if you want to be a really good student, the first thing is to study hard, that is, to dare to endure hardships, cherish time and study tirelessly. Establish confidence, firmly believe that you can learn any course well, firmly believe in the "law of conservation of energy transformation", and firmly believe that you should get several times if you pay a few times. Please read the following three quotations about this article:
I never believe in any innate or acquired talent, and I can succeed without firm and long-term efforts. -Dickens (English writer)
The main reason why some people can go far beyond others is not so much genius as his indomitable spirit of concentrating on his studies and not giving up until he reaches his goal.
-Dalton (British chemist)
The fastest and slowest, longest and shortest, most common and most precious, most easily overlooked and most regrettable thing in the world is time.
-Gorky (Soviet writer)
The first point mentioned above should be said to be the problem of learning attitude and thinking method. The second is to understand that there are eight links in learning as a student: making a plan → previewing before class → concentrating in class → reviewing in time → working independently → solving problems → systematically summarizing → studying after class. The most important thing here is: concentrate in class → review in time → work independently → solve problems → summarize systematically. In the above eight links, there are many learning methods. According to the characteristics of physics and how to learn physics well, some specific learning methods are introduced below.
(1) Sanji. Basic concepts should be clear, basic laws should be familiar, and basic methods should be skilled. Give an example about the basic concept. Like speed. It has two meanings: one is to express speed; The second is the ratio of distance to time (such as in uniform circular motion), and the speed is the ratio of displacement to time (in uniform linear motion). There are two formulas for calculating basic laws, such as average speed, V=s/t and V=(vo+vt)/2. The former is a defined formula, which is applicable to any situation, and the latter is a derived formula, which is only applicable to the case of uniform linear motion. First of all, the basic methods commonly used to study middle school problems, such as holism and isolation, are typical supplementary methods. Finally, another question belongs to three basic problems. That is, in the process of learning physics, we sum up some concise and practical inferences or conclusions, which are very useful for solving problems and learning physics well. For example, "the potential decreases along the electric field line"; "The tension on the same rope is equal"; "Maximum speed when acceleration is zero"; "Lorentz force does not do work" and so on.
(2) Do the problem independently. Do some problems independently with good quality and quantity (meaning not relying on others). There must be a certain number of topics, not too few, but also a certain quality, that is to say, there must be some difficulty. Anyone who studies mathematics and physics can't learn this level well. Solving problems independently may sometimes be slow, sometimes you have to take detours, and sometimes you can't even solve them, but these are normal and the only way for any beginner to succeed.
(3) Physical process. To clarify the physical process, there must be hidden dangers in solving problems if the physical process is not clear. No matter how difficult the topic is, try to draw as much as possible, some can draw sketches, and some need to draw accurate pictures, using compasses, triangles, protractors and so on. To represent geometric relationships. Drawing can turn abstract thinking into image thinking and master physical process more accurately. With this diagram, we can make state analysis and dynamic analysis. State analysis is fixed, dead and discontinuous, while dynamic analysis is alive and continuous.
(4) attending classes. Listen carefully in class and don't think or think as little as possible. Don't be self-righteous, learn from the teacher modestly. Don't give up listening just because the teacher speaks simply. If this happens, it can be regarded as review and consolidation. Try to be consistent and synchronized with the teacher, and you can't do it yourself, otherwise it will be self-study. After getting started, with a certain foundation, you are allowed to have your own activity space, that is, you are allowed to have something of your own. The more you learn, the more things you have.
(5) notebook. Class is mainly based on listening, and there are notebooks, and some things should be written down. Knowledge structure, good problem-solving methods, good examples, places you don't understand, etc. Should be recorded. After class, you should sort out your notes, on the one hand, you should "digest" them, on the other hand, you should supplement your notes. Notebook is not only to remember what the teacher said in class, but also to make some reading notes. Good problems found in homework and good solutions should also be recorded in a notebook, which is what students often call a "good problem book". Hard-won notebooks should be numbered, studied later and kept for life.
(6) learning materials. Learning materials should be well preserved, classified and marked. The classification of learning materials includes exercises, papers, experimental reports and so on. Marking refers to, for example, marking exercises. General questions are not marked. Good questions, valuable questions and error-prone questions are marked differently for future reading. Marking can save a lot of time.
(7) time. Time is precious. Without time, there is no time to do anything, so we should pay attention to making full use of time, which is a very superb art. For example, we can save time by "recalling" learning methods. Before going to bed, waiting for the bus, walking on the road, etc. We can recall the lessons of the day section by section, so that we can learn them again and again and achieve the goal of strengthening. Some physics problems are more difficult, and some problems may be solved on foot. People who study physics often have several problems in their minds that they can't do and won't forget. I don't know when they will make a breakthrough and find the answer to the question.
(8) learn from others. We should learn from others, from our classmates, from people around us and see how others learn. We should often have "academic" exchanges with them, teach each other, learn from each other and improve together. We must never be self-righteous. Cann't be conservative Tell others if you have a good method, so that others will tell you that you have a good method. You should have some good friends in your study.
(9) Knowledge structure. We should attach importance to the knowledge structure, master it systematically, and systematize scattered knowledge. From the whole knowledge structure of physics to the knowledge structure of mechanics, even to chapters, such as the knowledge structure of statics and so on.
(10) Mathematics. The calculation of physics depends on mathematics, which is too important for learning physics. Physics is difficult to do without mathematics as a calculation tool. In the physics department of the university, mathematics and physics are equally important. To learn mathematics well, we must make good use of this powerful tool.
(1 1) Sports activities. Healthy body is the guarantee of good study, and vigorous energy is the guarantee of high efficiency in study. You should always take part in sports activities, know one or two kinds of exercise methods, take part in sports activities all your life, and do sports activities continuously. Just because you are interested in fishing for three days and drying the net for two days, it will not do much good to your health. Consciously exercise. To ensure adequate sleep, it is not advisable to increase study time by reducing sleep time. You can't get some good grades at the expense of overdraft health. We can't talk about the so-called "sprint" and "struggle" at every turn. We should also pay attention to regularity in our study, that is to say, we should always work hard and not engage in surprise attacks.
The above has briefly talked about some learning methods. More specific and effective learning methods need to be explored and summarized by themselves in the learning process, and others' methods need to be tested by themselves before they can become their own things.
First, enter the material world with a thirst for knowledge.
Physics is no stranger to us. Around us, all kinds of physical phenomena happen all the time, from the whole universe to our side. The ever-changing scientific and technological information is like a kaleidoscope of colors. Q: "How high is the sky?" It is necessary to study the atmosphere and beyond. In nature, there will be earth-shattering lightning that will cut through the sky. However, did you notice the thunder and electricity that happened to you? Telephone brings a lot of convenience to human communication. What are its shortcomings? Perhaps many students have seen the acrobatic Flying Over the Wall. On the steep wall, a motorcycle or car is driving at high speed, but it won't fall down. The actor sitting in the car looks very relaxed. When you are surprised, you may admire the actor's superb acting skills and extraordinary courage. In fact, these are all using some mechanical principles in physics. Why should large tractors and tanks be equipped with tracks, and bicycle wheels, tires and wire cutters should have patterns? Why can a thermos keep an object "high temperature" and "low temperature"? After learning physics, you can get the answers to these questions.
Einstein said: Interest is the best teacher. As a student who has just entered the hall of physics, the first thing he needs is interest. The movement and change of all things in nature, as well as everything created by human beings, are inexhaustible sources of our interest. Let's ignite a strong spark of knowledge in our hearts, walk into the world of physics with strong interest, experience the power of our wisdom in learning and experience the joy of seeking knowledge. Let a strong thirst for knowledge keep you persistent.
Second, reading is an important way to acquire physical knowledge.
Open the history of every scientist's successful struggle and see the chapter of "fascinated" reading. To read, we must first read the textbook carefully. Physics textbooks are written after a long period of teaching practice, telling the most basic knowledge of the subject and containing the wisdom of "scientific giants". When reading textbooks, don't "read ten lines at a glance", but carefully consider one concept and one formula according to the teacher's guidance, and digest and absorb it repeatedly. Pay attention to the idea in the article ~ what problem does it want to explain and how to explain it. For key paragraphs and key contents, we should read them carefully and understand them word by word. Pay attention to the characteristics of physical interpretation problems-there are facts and sufficient reasons. For the examples in the book, we should not only see how it applies the formula, but also see how it analyzes the problem, whether it can be redone after closing the textbook and whether it can be done in other ways. After learning each chapter, you should also make a summary of the whole chapter, organize the content into systematic content purposefully, and master it systematically. We should also learn to use the knowledge of textbooks to explain some common phenomena. Don't rush to finish your homework without reading the textbook, so you will never learn the basic knowledge of physics well.
In addition to intensive reading of textbooks, students can also read more physics extracurricular books and periodicals extensively. It doesn't matter that you may encounter something you don't understand or understand very well in reading. It is also beneficial to know that there is such a thing from reading. The main significance of this kind of reading is to broaden our horizons, expand our knowledge and let our thinking and imagination soar in a broader material world.
Third, be willing to observe and be good at observing.
Observation is also one of the important methods of learning. Each of us, from infancy. Because I am curious about the ever-changing phenomena around me and observe them carefully, I have gradually accumulated a lot of experience in my daily life. These experiences are true and false, so we should discard the false and keep the true. Especially when studying physics, we should seriously adopt the method of observation, from simple curious observation to purposeful observation.
How to make a purposeful observation? First of all, when learning physical concepts and laws, we should dig up a lot of relevant experience accumulated through daily observation, and discard the false and retain the true. For example, when an object is stressed, is it possible that no other object acts on it? Among all kinds of substances in daily contact, which are easy to transfer heat and which are difficult to transfer heat? Based on correct experience, we should deeply understand relevant knowledge.
Observe the demonstration experiment with a clear purpose. Before doing the demonstration experiment, the teacher often talks about why to do the experiment, what instruments to use, how to place the instruments and how to do the experiment, hoping that students can observe something. These words are very important and are the basis of our observation. We should all listen carefully, think while listening and think about what results we will get.
You must concentrate on the demonstration experiment, because the demonstration experiment is done on the podium, the instrument is sometimes very small, and the experimental phenomena often change rapidly. You need to concentrate on the phenomenon, and it is most taboo to look at the results without looking at the process. Be sure to follow the teacher attentively and watch every step change. Every step of the experiment is fast, slow, fast, slow and patient. Many experiments are usually divided into several steps. For example, in a demonstration experiment that proves that a moving car stops due to resistance, the car is allowed to slide down an inclined plane with the same height for three times, and surfaces with different smoothness are placed on the table for three times. We should pay attention to the fact that the three heights are the same, and think about why, and then pay attention to the difference in the distance that the car travels on three different surfaces, what different conditions these three different surfaces provide, and so on.
Observing the demonstration experiment, we should not only observe and think, but also continue to think after the experiment. In addition to drawing conclusions along the direction of the teacher's guidance, we should also think about what are the imperfections of this experiment and whether we can propose better experimental methods. Moreover, contact this demonstration experiment to see what similar phenomena exist in daily life. For example, in connection with the experiment mentioned above, it is easy to think that if you ride a bicycle down a slope, you will run farther on the asphalt road than on the sand road.
Fourth, do experiments with your hands and brain.
Experiment is a very important part of learning physics, which can deepen our understanding of physics knowledge and cultivate our ability. Do it yourself in the experiment, observe, analyze and summarize, and solve the following problems:
1. Through experiments, we have a rich and vivid perceptual knowledge of many abstract physical concepts and laws, which is easy to understand. For example, the three-state change of matter, from solid to liquid, will absorb heat, and the temperature will remain the same when the crystal melts. These phenomena will be convinced and left a deep impression after benzene melting experiment.
2. Through hands-on operation, you can know more about the structure and performance of various physical instruments and devices, and know how to use commonly used instruments correctly. All kinds of basic instruments and devices used in physical experiments are the basis of all kinds of instruments and devices used in industrial and agricultural production and scientific research in the future. Learn to operate today, and you will have the skill base of operation later.
3. Master some basic measurement methods in the experiment. For example, to measure the diameter of a thin metal wire, the method of "multiple measurements" is adopted; "Substitution method" and "comparison method" can be used to determine the unknown resistance value; In order to reduce the experimental error, the average value of many measurements is taken and so on. The basic methods of these experiments will greatly improve our experimental ability.
We should develop good experimental habits in the experiment. Observe laboratory discipline and take good care of instruments; Fully prepared before the experiment class; Carefully operate, carefully observe, truthfully record and complete the experiment on time; Keep clean, do a good job of sorting out and complete the experimental report. Only by developing these good experimental habits and qualities can you become an excellent producer and scientist in the future.
Five, use your head and think about it.
Without positive thinking, it is impossible to really understand physical concepts and principles. From junior high school, we should form the habit of positive thinking.
To understand and master the concept of physics, it is necessary to study and think about how this concept was introduced. What is the definition? What's the physical significance? For example, for resistance, it needs to be clear: what experimental fact was the concept of resistance introduced? What is the definition of resistance? How is its unit stipulated? How to measure the resistance of a conductor? Wait a minute.
It can only be identified by comparison. The application of contrast method is to distinguish some concepts and laws well in the process of learning physics, so that they will not be confused, so as to correctly understand these concepts and laws.
First of all, when you come into contact with every new physical concept or law, you should compare it with the concepts that have been formed in daily life to see which ones are consistent and which ones are different, and correct the vague views on concepts in life. For example, force is the action of objects on objects, which is the reason for the change of object speed. However, in daily life, there is often such a wrong perceptual knowledge that it is necessary to exert force to keep an object moving at a constant speed. We must compare this wrong view, so as to correctly grasp the concept of force, understand the inertia of objects, and analyze problems by using the law of inertia, so as not to make mistakes.
Secondly, compare the interrelated concepts we have learned before and after, such as mass and density, pressure and pressure, work and power, heat and specific heat. The former is the basis of the latter, and the latter is the extension of the former. There are both connections and differences, so we should compare them from the aspects of definition, physical meaning, unit and practical application. Some similar concepts and laws can be compared by tabular method, such as the concepts and characteristics of series and parallel circuits.
In physics learning, we should also often use the analytical and comprehensive thinking method. For example, to learn simple machinery, we must first analyze the characteristics of different simple machinery (lever, axle, moving pulley, crown block and so on). ), and then summarize their similarities and differences: they are all different forms of levers, so the relationship between power and resistance is calculated according to the balance conditions of levers; They all follow the principle of work, and they can only save energy and can't work.
Six, the correct use of mathematical tools.
Mathematics is an important tool for studying physics. When studying physics, you must make good use of this tool. When applying mathematical tools to study physics, we should pay attention to the following points:
(1) We should combine the mathematical formulas of concepts and laws with the narrative of words and languages to truly understand the physical meaning of the formulas, instead of simply understanding the formulas from the purely mathematical relationship to avoid making mistakes in the physical meaning. For example, the definition of the density of matter is d = m/v. Can we say that the density ρ of matter is directly proportional to the mass m and inversely proportional to the volume v according to the mathematical relationship of this formula? No, because density ρ is a physical quantity that describes the inherent characteristics of each substance. For example, the density of aluminum is 2.7 X 103 kg/m3. Whether aluminum is made into small rivets or large aluminum blocks, ρ is this value. How can it be said that mass is directly proportional to volume? Therefore, the formula ρ=m/v only provides a method for measuring and calculating density, that is, when measuring the mass and volume of an object, this formula can be used to calculate the density of substances that make up this object.
(2) When doing physical calculation reasoning, we should combine physical calculation with concise literal reasoning, so that the physical thinking in the problem-solving process is clear and the method is concise and rigorous. The physical meaning of the calculation results should also be clear.
(3) We should get into the habit of using graphics to represent physical processes and laws, such as drawing stress diagrams of objects, simple mechanical diagrams, melting curves of crystals, motion diagrams of objects, light path diagrams, etc. Consciously learn to draw pictures according to the topic, understand the meaning of pictures, improve the ability to use pictures correctly, and overcome the bad habit of not drawing pictures or doing exercises without pictures.
Seven, do exercises.
After each unit of the text, there are some exercises. These exercises can be divided into four categories:
1. Questions and answers. After describing some physical phenomena, some questions such as "what", "why" and "how" are put forward, which require us to analyze and answer with the physical concepts and laws we have just learned.
2. discuss the problem. According to the physical phenomena and conditions put forward in the topic, we apply physical laws to analyze and compare them, study possible changes, and answer questions such as "what", "how to change" and "how is the situation".
3. Calculation problems. According to the known values provided by the topic, the unknown results are calculated by applying physical laws and formulas.
4. Experimental questions. Apply the experimental instruments provided, or connect lines, or conduct experiments to verify physical laws, or determine some numerical values, for analysis, judgment and discussion.
The above categories 1, 2 and 4 are also called reasoning questions (the fourth category should also be inferred on the basis of experiments).
Let's focus on the problem of explanation.
Reasoning is very important. In junior high school physics exercises, it occupies a large proportion. The first volume, 184 exercise questions, 1 15 reasoning questions, accounting for 63%. If you ignore it, you will ignore the main content of extracurricular exercises. If completed, you can learn to apply physical knowledge to solve practical problems, consolidate and deepen your understanding of physical concepts and laws, and cultivate your own logical reasoning ability and comprehensive analysis and problem-solving ability. So ... we must finish every reasoning problem carefully.
How to solve the reasoning problem? We should do the following:
1. Carefully analyze the meaning of the topic, correctly understand the requirements of the topic, understand the physical phenomena it tells, what the known conditions are, and what questions we are required to discuss and answer.
2. Determine what physical phenomenon or process it belongs to, and determine the basis for solving the problem. To accurately apply physical concepts and laws, the conclusions should be scientific, not vague or ambiguous.
3. Answers should have arguments and be clear, and the process should not be reversed, and the cause and result should not be confused.
4. Use your own words, be concise and don't repeat them.
Eight, not only to understand, but also to remember.
We oppose the method of memorizing without understanding physical concepts, laws and formulas. We must learn to memorize a large number of physical concepts, laws, formulas and units in a scientific way on the basis of understanding, and become information in our knowledge database. The knowledge learned in front is the basis of learning later. High school should apply what they have learned, and universities should apply what they have learned. Remember what you have learned, and then you can extract information from the brain database. If you don't remember what you have learned, there will be no solid foundation and no building of knowledge.
How can I strengthen my memory?
Understanding is the basis of correct, complete and consolidated memory. Only through analysis and synthesis can we strengthen and deepen our understanding of knowledge and remember it deeply. To analyze a concept, we should highlight its elements and grasp the key. For example, when analyzing the concept of work, we should pay attention to its two elements: force and distance. A key point is that distance refers to the distance traveled "in the direction of force". Some similar concepts and laws need to be compared with each other, and knowledge will be constantly strengthened and improved through constant comparison and contact, and printed in the mind.
Repeated introspection and repeated application are necessary steps to consolidate memory. Some people think that if you understand it, you can remember it. This is a misunderstanding of the laws of human thinking and memory. A person has seen and understood countless things in his life, but only a few (less than 5% according to statistics) often act on our minds and apply them repeatedly to remember them. Therefore, every after-class review, unit review, problem-solving application, experimental operation, semester and school year review, etc. There should be plans and arrangements to continuously consolidate your memory.
Nine, learning knowledge, learning methods, long ability
What will we learn in junior high school physics class? Many students will answer without thinking: "study physics." This answer is only half right at best. Because learning physics, we should not only master the basic knowledge of physics, but also master some methods of learning natural science, and cultivate the ability to engage in production and explore unknown things. As long as you follow the correct learning method, you can learn quickly and well in the learning stage, and after taking part in the construction work, you will have the ability to work independently and invent.