In my second year of junior high school, I seem to understand physics, but I get a lot wrong every t

Listening and doing are two different things, which requires you to do more questions and think more. Practice makes perfect, don't be discouraged. I've been like this before, and I'll be fine if I think about it more.

This question is very difficult, I can only say that I listen carefully, do more questions, think carefully, and really don't understand the questions must be asked to the teacher in time, and the good topics are specially remembered in a notebook, and generally this will not make too many mistakes in homework and exams.

First of all, you don't understand it very well, the conditions for the use of formulas are not clear, and physics is actually very simple. Mostly formulas. To learn the reasoning of formulas, the principle that a formula has a source to a source, start with the formula.

Lay a solid foundation, don't look at the masters, first improve the accuracy of simple questions, and then pursue more challenging problems.

- First of all, you should study physics and establish the right study method, you can't study for exams, if you are probably going to lens imaging now, you can do more experiments on your own.

You have to understand the meaning of each sentence and use the formula flexibly, it is recommended that you find more questions on the Internet to do, and if you don't know it, ask the teacher or smart classmates.

Think more, and after doing each question, think about it and be good at summarizing.

Just ask your mother to find you a beautiful tutor.

Let's take a look at the textbook! In a word, physics depends on understanding!

Not careful! Besides, it's not careful!

Figurative thinking is built in the brain.

The details were not taken care of.

It seems to mean that it means to understand what it means to have something to do and to do it yourself more to understand and understand the use of fart.

Mathematics and physics can only do more problems, and I won't push the formula myself, I think it's easy to remember and learn quickly.

Don't worry, it's only the second year of junior high school, physics has just been learned, and doing more mathematics will definitely have an effect.

Hehe.. I've always been good at physics... Hehe, I'm proud of that.

Buy a full explanation of the middle school textbook and read it for yourself.

Do more questions, organize your notes in class, and go home and review more.

If the physics is not good, analyze the reasons for the bad ones, and then make targeted adjustments.

The reasons for this are generally as follows:

Students have a bad attitude towards learning.

Poor student approach.

The teacher is not good at teaching.

As for the question of attitude, it can generally be seen from the teacher's evaluation and the situation of other subjects, and a little test in each subject indicates that his mind is not on learning, which is a family reason, and it may also be a long-term accumulation reason.

It is also possible that the teacher's teaching method is not good, and now generally speaking, there are quite a lot of teachers who do not understand the teaching method very well, and rely on the gourd to draw a scoop and self-imagination, lacking unique and profound insights and painstaking study, so sometimes, there are many unscientific places in the teaching method, and some teachers even make some principled and common-sense mistakes. Therefore, it is inevitable that the children of the wrong people will be mistaken.

The so-called chopping firewood is not in accordance with the text, and the woodcutters are tired to death. There is no good way, and students sometimes learn very hard, but the efficiency is very low.

First, the study of physics must be combined with its own characteristics, that is, physics is a discipline that is very closely related to the reality of life, do not immerse yourself in the rote memorization of physical knowledge and concepts, jump out, and think about how this is different and similar to the phenomena we see in our lives.

Second, they must have their own independent thinking, and good children in Chinese education tend to listen carefully and understand and absorb what the teacher says. In fact, this is still far from enough, but also requires bold understanding and speculation, for example, why is this so? Ask yourself more, if you don't know, ask teachers or classmates, in this kind of questioning and speculation, the mastery of knowledge points will play a very good role in promoting, and this way of thinking about problems will also benefit for life.

Third, don't memorize conceptual formulas, but learn and apply them, there are not many formulas and concepts, but there are many types of questions around these conceptual formulas, you should practice more, after the connection, if you do it wrong, not only to understand what is going on correctly. It's best to summarize more, see if there are any similarities and differences in the questions you have done, especially similar question types, and find out the rules, fourth, take the initiative to participate, take the initiative to answer questions in class, and use your hands and brains more when doing experiments, instead of being lazy and afraid of moving, the more afraid you are, the more afraid you are, you can't experience the joy of answering questions, you can't get the happiness of experiments, and without the promotion of happy experience, it is difficult to learn well.

Diagnosis: This is the lack of a thorough understanding and awareness of concepts and knowledge points.

Prescribe a prescription: You don't need to buy too much of the teaching aids, first of all, refer to the teaching aids to thoroughly understand the concepts in the textbook. Then, do the questions again, the questions are also for a better understanding of the concept and the mastery of the knowledge points, as long as you have mastered a knowledge point, it is like a waste of physical strength and time to do its questions, so as long as you master the knowledge point, you don't have to do so much.

Finally, it is to summarize and reflect on the completed questions. That's the general idea.

Qualities of ability improvement: Counter the opposite.

3. Multi-directional thinking, summarizing ability, and forming a knowledge network structure.

Note: Doing 10 questions is not the same as doing fine questions.

You do the problem three times, then copy the problem again on a blank piece of paper, and memorize the concepts and formulas used before doing the problem. It's best to remember that you know very well.

There are too few types of questions, do more questions, focus on understanding the method, and it will improve after a while.

1.Pay attention. When learning physics, we should first pay attention to observing the physical phenomena given by the teacher and the textbook, such as the questions raised in the textbook, the ** given, the experiments and the teacher's demonstration experiments.

The main aspects of observation are: the conditions under which physical phenomena or facts arise, the forms in which they manifest themselves, such as motion, deformation, temperature changes, results, etc. Secondly, we should consciously cultivate our habits and interests in observing physical phenomena in our lives.

2.It is necessary to pay attention to learning and summarizing the problem-solving methods of physics to help oneself gradually improve one's thinking ability. There is no special chapter in physics textbooks that introduces the learning methods of physics.

However, it can be said that the whole textbook is about the problem solving method of physics. This is because when textbooks explain physical concepts, laws, and formulas, they follow the steps of physics to solve problems. That is, questions are generally raised first, and then carried out through experimental research, observation, analytical reasoning, generalization and other steps.

Therefore, in the whole process of physics learning, while learning the problem-solving steps of the textbook, you should also pay attention to thinking to see if you can come up with experiments, methods and steps to solve the problem that are different from those in the textbook. In this way, while learning to inherit the thinking achievements of predecessors, they can also exercise and improve their ability to solve problems and innovate ability.

3.Pay attention to the method of memorization. Although learning junior high school physics requires attention to cultivating thinking ability, it is also necessary to pay attention to memory, and to memorize on the basis of understanding, rather than mechanical memory.

When memorizing, we should pay attention to finding patterns and characteristics, and be accurate. It is necessary to accurately memorize the various definitions, the literal expressions of the laws, and the "units" of various physical quantities. This is conducive to helping us form the ability to express physical words and language.

One of the biggest differences between physical formulas and mathematical formulas is that each factor in the formula has a "unit". Therefore, when memorizing the expressions of physical formulas, it is important to remember the physical units of each factor.

4.It is necessary to pay attention to experimentation and do as many experiments as possible. If you can't do experiments, you can't say that you have learned physics well.

Experimental hands-on ability mainly refers to hands-on ability such as observation, operation and production. When you start learning physics, you can pay attention to how the teacher does all kinds of demonstration experiments, such as the steps of the experiment, what to do first, what to do later, and the method of the experiment. When doing experiments, carefully experiment and practice according to the experimental steps and methods required by the teacher.

We should actively find ways to do the exploratory experiments and small productions on learning physical concepts and laws given by teachers and textbooks. This is very beneficial for enhancing hands-on ability. In addition, you can design your own experiments.

For example, if you want to design the experimental procedures and methods implicit in the illustrations and exercises in the textbook, you can design the experimental procedures and methods by yourself and conduct experiments. This develops your ability to innovate and solve problems hands-on.

Physics is actually very closely related to life... Add a little math and that's pretty much it.

There are a lot of things to memorize in the second year of junior high school, so let's memorize more、、、

Read the book, read carefully, there will always be a harvest, if you really don't understand it, buy a reference book, there will be a harvest, what you need is immediate action, defeat laziness, the problem is solved.

First learn to think rationally. Solve problems with rational thinking.

Buy some reference materials and learn all the subjects on your own, I am a typical self-taught person who understands all subjects. The key is to take good notes on the notes provided by the teacher first, and then understand and read more books. I understood a lot of knowledge.

The grades can still go up. For calculation problems, find a few example problems to see how people standardize the format of problem solving.

It's very simple, you can understand it by heart, and if you really don't understand, ask the teacher.

The exercises in the book are understandable and serious. Get another reference book and write it slowly, and that's it.

1. In fact, there is a current through the original resistance when the short circuit is short-circuited, but because I is inversely proportional to R, and the resistance of the wire is much smaller than the original resistance, so that most of the current passes through the wire.

2. The principle of the bulb is that the tungsten filament heats up to an incandescent state to produce light. Its brightness is related to temperature (not proportional, but the higher the temperature, the brighter the light), and the temperature is determined by the heating power, which p=r(i 2), so the higher the temperature, the greater the resistance, and the brighter the bulb.

1. Because he idealized the circuit, he thought that the resistance of the wire was 0. If the wire resistance is not 0, there is still a small current passing through the resistor in parallel with the wire during a short circuit.

2. "The higher the temperature, the greater the resistance", which corresponds to the filament of ordinary incandescent bulbs, but the brighter the bulb, it is not necessarily, and the brightness will not change significantly for the general situation of a certain voltage.

1. The conductor has a certain resistance, and the resistance of the general electrical appliance is large, and the resistance of the wire is very small, and the resistance of the wire (laboratory) is not more than 1m, and the resistance is close to 0, and there is almost no obstacle to the current. When a short circuit occurs, the wire is connected in parallel with the electrical appliance, and the branch where the electrical appliance is located obstructs the current, while the branch where the wire is located is not obstructed, so the current will not pass through the electrical appliance, but all of it will flow back to the negative pole of the power supply through the wire.

2. The higher the voltage at both ends of the small bulb (not too high, otherwise it will burn out), the greater the current through it, the brighter the bulb, resulting in an increase in the temperature of the filament, so the resistance increases, of course, the increase is not very large.

Let me explain them to you individually.

1。When the short circuit is actually the resistance and a wire in parallel, in fact, there is still a current on the resistor at this time, but because of the relationship between the parallel shunt, the current i = u r, u or r The voltage at both ends is unchanged, so the resistance is small, the current is large, because the wire resistance is very small, compared with the resistance of the access circuit, the difference is more than a few orders of magnitude, so the current of the wire is very large, and it is also a difference of several orders of magnitude, so we can approximate the current passing through the resistor r is 0, ignoring the current on r, i.e. a short circuit directly through the wire.

2。You're talking about a circuit in which a small bulb and a sliding rheostat are connected in series.

Because the resistance on the small bulb becomes larger, the proportion of the partial voltage in series becomes larger (u=i*r, the larger the series partial voltage, the larger the r, the greater the distributed voltage), so the more power on the bulb, so the brighter, this is only a qualitative analysis. Specifically, you can quantitatively analyze the relationship between the change of lamp resistance R lamp and the actual power p through P=I *R lamp and I=U power supply (R lamp + R sliding rheostat).

When the short circuit is shorted, the wire and the electrical appliance are connected in parallel, because the resistance r on the wire is much smaller than the resistance r of the electrical appliance, and the smaller the resistance when paralleling, the more shunts, so the current almost flows through the wire.

1. It may be that the previous course is the foundation, but you have not re-learned, and the foundation is not strong, and you will not be able to take the test well;

Second, it may be because there are many questions that you think you know, but in fact you don't. For example, when you do a question, you look at the answer first, and then do the question;

Third, it may be that your thinking is solidified, and a problem you will not be able to change the form a little.

1. Listen: Listen to the teacher and take notes carefully.

2. Think: Think carefully about the concepts, formulas, and topics that the teacher says. In particular, the conditions for the use of concepts are unclear, and it is easy to use formulas indiscriminately.

3. Practice: Do the example questions several times, and think more while doing it. In this way, we can deeply understand the conditions of formulas, concepts.

4. Imitation: find similar questions to practice, and continue to accumulate and expand. Skill comes from practice.

In this way, you can learn that you must not be lazy with your hands and brains.

Believe in yourself, and you will definitely learn well.