For this task, you can get 1 point on the exam in 2020

The topic of the 1st exam in physics is kinematics and everything related to this section of science. Typically, the first question on the ticket is not difficult for students, especially if the type of question is graph analysis. You will be offered a graph of any dependence - body speed versus time, path versus time, or the spatial position of the body, by which you need to determine the value of one of the quantities at a given point. The answer to this question needs a short, numerical value with the desired unit of measurement. In this case, in the form of answers, it will be enough just to indicate the required number.

In task 1 of the USE in physics, the uniform, equally variable motion of a body, as well as movement in a circle, can be considered, including questions regarding pendulums and cosmic bodies. In any case, the assignment will present a schedule that the student should carefully study and then answer the question.

Preparation for the exam in physics. The most important recommendations.

But, firstly, one must understand that one must prepare for the exam not the day before, but in advance.

I recommend even starting at grade 10. Why from grade 10? Because from the 10th grade there is a repetition and systematization of important sections of physics - mechanics, molecular physics and electrodynamics. If you are late, you can start from September 11th grade. But by no means since the spring of 11th grade.

I will briefly tell you the structure of the exam in physics.

There are 31 tasks in total.

In the first part - 23 tasks.

The first 7 tasks are devoted to mechanics.

1 task - find the kinematic value according to the graph. Here it is necessary to remember the formulas of uniform and uniformly accelerated motion and represent them graphically.

2 task associated with finding strength.

3rd and 4th task - about mechanical work, condition of balance, energy.

5 task - choose 2 correct out of 5 statements. Usually this task is difficult.

6 task - how this or that value will change if another value is changed.

7 task

8 - 12 tasks - relate to molecular physics and thermodynamics:

8 - 10 task solve simple tasks.

11 task - choose 2 correct statements.

12 task - establish compliance.

Basically, here you need to know the Mendeleev-Clapeyron equation, the Clapeyron equation, isoprocesses, the first law of thermodynamics, the amount of heat, the efficiency of a heat engine, and present a graphic representation of isoprocesses.

13 - 18 tasks - electrodynamics.

By 13 assignment it is imperative to know the gimlet rule (right hand rule), the left hand rule to determine the Ampere force and the Lorentz force. Not just to know, but to be able to apply to a particular situation. In this task, we write the answer in a word or words: up, down, right, left, from the observer, to the observer.

14 task - often, according to the scheme, determine the current strength, voltage, resistance, power, or the ratio of these quantities.

15 task - either associated with optics, or with electromagnetic induction (grade 11).

16 task - again choose the correct 2 statements out of 5.

17 task - how the electrodynamic quantity will change when another quantity changes.

Task 18 - to establish a correspondence between physical quantities and formulas.

19 - 21 tasks - nuclear physics.

19 task usually to determine the numbers of protons, neutrons, nucleons, electrons.

Task 20 - the equation of the photoelectric effect, which is easy to remember.

21 tasks - for the conformity of processes.

22 task associated with an error. I want to note that here we need to equalize the digits after the decimal point. For example, in the answer we received 14, and the error of this value is 0.01. Then we write in response: 14,000,01.

V 23 tasks usually investigate the dependence, for example, of the stiffness of a spring on its length. Therefore, we are looking for material, the mass of the cargo is the same, but the length is different. If you do all 1 part without mistakes, you get 33 primary points, or 62 points.

In the second part, the 3 first tasks are still filled in form 1, for which 1 point is awarded.

24 task - a task for mechanics,

Task 25 - a problem on molecular physics and thermodynamics,

26 task - a task for electrodynamics, optics.

If you solve them, you will already score 69 points. That is, if you do not proceed to form number 2, you are already gaining 69 points. For some, this is a very good score.

But basically, you will make a mistake somewhere, so you need to start part 2. As I call part C. There are 5 tasks.

From 27 to 31 tasks are given 3 points.

27 task - high quality. This task must be described, indicate what physical laws you used. Here you basically need to know the theoretical material.

28 task - a difficult task in mechanics.

Task 29 - a problem in molecular physics.

Task 30 - a difficult task in electrodynamics, optics.

31 tasks - a task for nuclear physics.

Moreover, in Form No. 2, it is necessary to write down all the formulas, all conclusions, the units of measurement should be converted to SI units, the correct calculation should be made and the answer to the problem must be written down. It is most correct to deduce the final general formula, substitute all units in SI, not forgetting about the units of measurement. If you get a large number, for example, 56,000,000 W, do not forget about the prefixes. You can write 56 MW. And in physics it is allowed to round off in part C. Therefore, do not write 234.056 km, but you can simply write 234 km.

If you complete 1 complete task from the difficult part + part 1, you gain - 76 points, 2 tasks - 83 points, 3 tasks - 89 points, 4 tasks - 96 points, 5 tasks - 100 points.

But in fact, it is very difficult to get the maximum score for the task, that is, 3 points. Usually a student, if decides, then gains 1-2 points. Therefore, I will say whoever gets 80 points is smart and well done. This is a person who knows physics. Because the whole exam is given 4 hours.

The minimum threshold for physics is 9 primary points or 36 secondary points.

Choose 2 correct statements out of 5, if 1 and 4 are correct, then you can write down both 14 and 41 in the form. If the task is for compliance, then be careful, the answer is the only one here. If the task is to change the value, then the numbers can be repeated, for example, one and the second value increases, then write 11. Be careful: no commas, no spaces. For these tasks, score 2 points.

It is not necessary to hire a tutor, you can prepare for the exam yourself. Now there are so many sites for preparing for the exam. Spend at least 2 hours a week on physics (who needs it). Who goes to tutors, he rarely sits down on an independent decision, they believe that he gives them everything. They make a huge mistake though. Until the student begins to solve himself alone, he will never learn to solve problems. Because with tutors, it seems like all the tasks are simple. And on the exam, no one will tell you, not even the idea of ​​the problem. Therefore, after the tutor, be sure to decide for yourself, one on one with a book and a notebook.

If a student gets excellent grades in physics, this does not mean that he knows all physics, and he does not need to prepare for the exam. He is mistaken, because today he will answer, but tomorrow he may not remember. Real knowledge turns out to be close to zero. And it is not necessary to prepare any specific tasks, but to study physics completely. A very good problem book is Rymkevich. Therefore, at school I use it. Start a separate exercise book for preparing for the exam. On the cover of your notebook, write down all the formulas that are used to solve problems. We went through the mechanics at school, solve 1-7, 24, 28 tasks at once, etc. Very often, when solving physical problems, you need to add vectors, degrees, apply the Pythagorean rule, the cosine theorem, etc. That is, you cannot do without mathematics, if you are not friends with mathematics, you can get a failure in physics. A week before the exam, repeat all the formulas and solved problems in the notebook.

I wish everyone to write as well as possible and be more confident after preparing for the exam. All the best!

If you are going to enter technical specialties, then physics is one of the main subjects for you. This discipline is not given to everyone with a bang, so you have to practice in order to cope well with all the tasks. We will tell you how to prepare for the exam in physics if you have a limited amount of time at your disposal, and you want to get the best possible result.

The structure and features of the exam in physics

In 2018, the USE in physics consists of 2 parts:

1. 24 tasks in which you need to give a short answer without a solution. It can be an integer, fraction, or a sequence of numbers. The tasks themselves are of various difficulty levels. There are simple ones, for example: the maximum height to which a body weighing 1 kg rises is 20 meters. Find the kinetic energy at the moment immediately after the throw. The solution does not involve a lot of action. But there are also such tasks where you have to smash your head.
2. Tasks that need to be solved with a detailed explanation (recording the condition, the course of the decision and the final answer). All tasks here are of a fairly high level. For example: a cylinder containing m1 = 1 kg of nitrogen, during the strength test, exploded at a temperature of t1 = 327 ° C. What mass m2 of hydrogen could be stored in such a cylinder at a temperature of t2 = 27 ° C, having a fivefold safety factor? The molar mass of nitrogen M1 = 28 g / mol, hydrogen M2 = 2 g / mol.

Compared to last year, the number of tasks has increased by one (in the first part, a task on knowledge of the basics of astrophysics was added). There are 32 tasks in total that you need to solve in 235 minutes.

This year, schoolchildren will have more tasks

Since physics is a subject to choose from, the USE in this subject is usually deliberately passed by those who are going to go to technical specialties, which means that the graduate knows at least the basics. Based on this knowledge, you can score not only the minimum score, but also much higher. The main thing is that you prepare for the exam in physics correctly.

We suggest that you familiarize yourself with our tips for preparing for the exam, depending on how much time you have to learn the material and solve problems. After all, someone begins to prepare a year before passing the exam, someone a few months, but someone remembers the USE in physics only a week before passing! We will tell you how to prepare in a short time, but as efficiently as possible.

How to prepare yourself a few months before day X

If you have 2-3 months to prepare for the Unified State Exam, then you can start with theory, since you will have time to read and master it. Divide the theory into 5 main parts:

1. Mechanics;
2. Thermodynamics and Molecular Physics;
3. Magnetism;
4. Optics;
5. Electrostatics and direct current.

Work through each of these topics separately, learn all the formulas, first the main ones, and then the specific ones in each of these sections. You also need to know by heart all the values, their correspondence to one or another indicator. This will give you a theoretical basis in order to solve both the tasks of the first part and the problems from part # 2.

After you learn how to solve simple problems and tests, move on to more complex tasks.

After you have worked with the theory in these sections, start solving simple problems that take just a couple of steps to put the formulas into practice. Also, after a clear knowledge of the formulas, solve the tests, try to solve them as many as possible, in order not only to reinforce your theoretical knowledge, but also to understand all the features of the tasks, to learn how to correctly understand the questions, to apply certain formulas and laws.

After you learn how to solve simple problems and tests, move on to more complex tasks, try to build a solution as competently as possible, using rational ways. Solve as many tasks from the second part as possible, which will help you understand their specifics. It often happens that the tasks in the USE practically repeat last year's, you just need to find slightly different values ​​or perform the opposite actions, so be sure to look at the USE for past years.

The day before passing the exam, it is better to give up solving problems and repetition and just relax.

Preparation starts one month before the test

If your time is limited to 30 days, then you should follow these steps to successfully and quickly prepare for the exam:

• From the above sections, you should make a pivot table with the basic formulas, learn them by tooth.
• Review typical assignments. If among them there are those that you are good at solving, you can refuse to practice such tasks, devoting time to "problematic" topics. It is on them that you focus in theory.
• Learn the basic values ​​and their meanings, the order of converting one value to another.
• Try to solve as many tests as possible, which will help you understand the meaning of the tasks, understand their logic.
• Constantly refresh your head on the knowledge of basic formulas, this will help you get good points in testing, even if you do not remember complex formulas and laws.
• If you want to aim at high enough results, then be sure to check out the past USE. In particular, focus on part 2, because the logic of the tasks can be repeated, and knowing the course of the solution, you will definitely come to the correct result! You can hardly learn how to build the logic for solving such problems on your own, so it is advisable to be able to find commonality between the tasks of previous years and the current task.

If you prepare according to such a plan, then you will be able to score not only the minimum points, but also much higher, it all depends on your knowledge in this discipline, the base that you had before the start of training.

A couple of quick weeks to memorize

If you remembered passing physics a couple of weeks before the start of testing, then there is still hope to gain good points if you have certain knowledge, as well as overcome the minimum barrier if you are full 0 in physics. For effective preparation, you should adhere to such a plan. work:

• Write down the basic formulas, try to remember them. It is advisable to study well at least a couple of topics from the main five. But you should know the basic formulas in each of the sections!

It is unrealistic to prepare for the exam in physics in a couple of weeks from scratch, so do not rely on luck, but cram from the beginning of the year

• Work with the USE of previous years, understand the logic of tasks, as well as typical questions.
• Try to cooperate with classmates, friends. When solving problems, you can be well aware of one topic, and they are different, if you just tell each other the course of the solution, you will get a quick and effective exchange of knowledge!
• If you want to solve any tasks from the second part, then you better try to study last year's USE, as we described when preparing for testing in a month.

With the responsible implementation of all these points, you can be sure that you will receive the minimum allowable score! As a rule, people who started training in a week do not expect more.

Time management

As we said, you have 235 minutes to complete the tasks, or almost 4 hours. In order to use this time as efficiently as possible, first complete all the simple tasks, those in which you least doubt from the first part. If you are good "friends" with physics, then you will have only a few unsolved tasks from this part. For those who started training from scratch, it is on the first part that the maximum emphasis should be placed in order to gain the necessary points.

Correct distribution of your efforts and time on the exam is the key to success

The second part is time-consuming, fortunately, you have no problems with it. Read the assignments carefully, and then do the ones you know best first. After that, proceed to the solution of those tasks from parts 1 and 2, in which you doubt. If you don't have a lot of knowledge in physics, the second part is also worth reading at least. It is quite possible that the logic of solving problems will be familiar to you, you will be able to solve 1-2 tasks correctly, based on the experience gained while viewing last year's USE.

Due to the fact that there is a lot of time, you will not have to rush. Carefully read the tasks, delve into the essence of the problem, only then solve it.

So you can prepare well for the exam in one of the most difficult disciplines, even if you start your preparation when testing is literally "on the nose".

• Problem 25, which was previously presented in part 2 as a task with a short answer, is now proposed for a detailed solution and is estimated at a maximum of 2 points. Thus, the number of tasks with a detailed answer increased from 5 to 6.
• For task 24, which checks the mastery of the elements of astrophysics, instead of choosing two obligatory correct answers, it is proposed to choose all correct answers, the number of which can be either 2 or 3.

The structure of the USE assignments in physics-2020

The examination paper consists of two parts, which include 32 tasks.

Part 1 contains 26 tasks.

• In tasks 1–4, 8–10, 14, 15, 20, 25–26, the answer is an integer or a final decimal fraction.
• The answer to tasks 5-7, 11, 12, 16-18, 21, 23 and 24 is a sequence of two numbers.
• The answer to problem 13 is a word.
• The answer to tasks 19 and 22 is two numbers.

Part 2 contains 6 tasks. The answer to tasks 27–32 includes a detailed description of the entire progress of the task. The second part of the tasks (with a detailed answer) are evaluated by an expert commission on the basis of.

Themes of the exam in physics, which will be in the exam paper

1. Mechanics(kinematics, dynamics, statics, conservation laws in mechanics, mechanical vibrations and waves).
2. Molecular physics(molecular kinetic theory, thermodynamics).
3. Electrodynamics and basics of SRT(electric field, direct current, magnetic field, electromagnetic induction, electromagnetic oscillations and waves, optics, basics of SRT).
4. Quantum physics and the elements of astrophysics(particle-wave dualism, physics of the atom, physics of the atomic nucleus, elements of astrophysics).

Duration of the exam in physics

All examination work is assigned 235 minutes.

The approximate time for completing tasks for various parts of the work is:

1. for each task with a short answer - 3-5 minutes;
2. for each task with a detailed answer - 15–20 minutes.

What can be taken for the exam:

• A non-programmable calculator (for each student) with the ability to calculate trigonometric functions (cos, sin, tg) and a ruler is used.
• The list of additional devices and, the use of which is permitted on the exam, is approved by Rosobrnadzor.

Important!!! do not rely on cheat sheets, tips and the use of technical means (phones, tablets) during the exam. Video surveillance at the exam-2020 will be enhanced with additional cameras.

USE scores in physics

• 1 point - for tasks 1-4, 8, 9, 10, 13, 14, 15, 19, 20, 22, 23, 25, 26.
• 2 points - 5, 6, 7, 11, 12, 16, 17, 18, 21, 24, 28.
• 3 points - 27, 29, 30, 31, 32.

Total: 53 points(maximum primary score).

What you need to know when preparing assignments for the exam:

• Know / understand the meaning of physical concepts, quantities, laws, principles, postulates.
• To be able to describe and explain physical phenomena and properties of bodies (including space objects), the results of experiments ... give examples of the practical use of physical knowledge
• Distinguish hypotheses from scientific theory, draw conclusions based on experiment, etc.
• Be able to apply the knowledge gained in solving physical problems.
• Use the acquired knowledge and skills in practice and everyday life.

Where to start preparing for the exam in physics:

1. Learn the theory required for each assignment.
2. Train in physics test items designed based on

This article presents an analysis of tasks in mechanics (dynamics and kinematics) from the first part of the exam in physics with detailed explanations from a physics tutor. There is a video analysis of all tasks.

Let's select on the graph the area corresponding to the time interval from 8 to 10 s:

The body moved in this time interval with the same acceleration, since the graph here is a section of a straight line. During these s, the speed of the body changed by m / s. Therefore, the acceleration of the body during this period of time was equal to m / s 2. Graph number 3 is suitable (at any time the acceleration is -5 m / s 2).

2. Two forces act on the body: and. By strength and resultant of two forces find the module of the second force (see figure).

The vector of the second force is ... Or, which is similar, ... Then we add the last two vectors according to the parallelogram rule:

The length of the total vector can be found from a right-angled triangle ABC whose legs AB= 3 N and BC= 4 N. By the Pythagorean theorem, we obtain that the length of the sought vector is N.

We introduce a coordinate system with the center coinciding with the center of mass of the bar and the axis OX directed along the inclined plane. Let us represent the forces acting on the bar: gravity, the reaction force of the support and the force of friction at rest. The result will be the following figure:

The body is at rest, so the vector sum of all forces acting on it is zero. Including zero and the sum of the projections of forces on the axis OX.

Projection of gravity onto an axis OX equal to the leg AB the corresponding right-angled triangle (see figure). In this case, for geometric reasons, this leg lies opposite the angle at. That is, the projection of gravity onto the axis OX is equal.

The static friction force is directed along the axis OX, therefore the projection of this force onto the axis OX is simply equal to the length of this vector, but with the opposite sign, since the vector is directed against the axis OX... As a result, we get:

We use the formula known from the school physics course:

Let us determine from the figure the amplitudes of steady-state forced oscillations at frequencies of the driving force of 0.5 Hz and 1 Hz:

The figure shows that at a driving force frequency of 0.5 Hz, the amplitude of steady-state forced oscillations was 2 cm, and at a driving force frequency of 1 Hz, the amplitude of steady-state forced oscillations was 10 cm. Consequently, the amplitude of steady-state forced oscillations increased 5 times.

6. A ball thrown horizontally from a height H with an initial speed, during the flight t horizontal flying distance L(see figure). What will happen with the flight time and the acceleration of the ball if the height is increased at the same setting with a constant initial velocity of the ball H? (Neglect air resistance.) For each value, determine the corresponding character of its change: 1) will increase 2) decrease 3) will not change Write down the selected numbers for each physical quantity in the table. The numbers in the answer may be repeated.

In both cases, the ball will move with the acceleration of gravity, so the acceleration will not change. In this case, the flight time does not depend on the initial speed, since the latter is directed horizontally. The flight time depends on the height from which the body falls, and the higher the height, the longer the flight time (the body takes longer to fall). Consequently, the flight time will increase. Correct answer: 13.