Characteristics of test materials
Diagnostic work was carried out in order to determine the level of mastering by 8th grade pupils of the subject content of the physics course for the 7th and partially 8th grades according to the passed program and to identify the elements of content that cause the greatest difficulties.
A set of tests (3 options) was developed to conduct a start-up diagnosis of knowledge and skills in physics of 8th grade students. The proposed tasks were aimed at diagnosing assimilation basic elements content of the physics course in grades 7-8, necessary for the successful continuation of the study of physics in grades 8-9.
The diagnostic work covered educational material in the following sections:
1) the structure of matter (molecules; structure of solids, liquids and gases; thermal motion of molecules);
2) thermal phenomena (internal energy and methods of its change; amount of heat; melting and crystallization, evaporation and condensation; the law of conservation of energy in thermal processes);
3) electrical phenomena (electrification of bodies; conductors and insulators; the law of conservation of electric charge).
The diagnostic work checked the formation of the following activities:
- knowledge of physical concepts and quantities;
- knowledge and understanding of physical laws;
- understanding of physical phenomena and processes;
- the ability to use physical devices;
- the ability to solve problems.
Each variant of the diagnostic work consisted of 10 tasks: 8 tasks with the choice of one correct answer out of four proposed and 2 tasks with a short answer.
The work presented tasks of basic and reduced levels of complexity. Tasks with a short answer were evaluated at 2 points. For the correct fulfillment of the remaining tasks, 1 point was given. Maximum score, which could be obtained for the correct execution of all the work - 12 points. Time to complete the work - 40 minutes.
Scale for setting marks for the test in accordance with the range test points is presented in table 1.
Table 1
The main results of the diagnostic work
Physics work was carried out by 3 students of the 8th grade: Jamilya, Timur, Andrey.
The distribution of students by the number of test scores received is shown in diagram 1. Average test score is 9.5 points, the average percentage of the test is 56%.
Table 2 shows the distribution of marks received for the performance of the diagnostic work, and the average score of the test by students with different levels of development. The share of students who did not achieve a sufficient level of mastery of educational material (completed less than 4 tasks) was 1% (Andrey).
Only Timur from the number of those tested showed a good level of preparation, but none of the students scored the maximum score.
Table 2.
Analysis of the results of performing diagnostic work in physics
Table 3 and Diagram 1 show the average results of assignments for the tested topics.
Table 3
| the date | Controlled content element | Average% completion |
| 07.12.15 | Structure of matter | 71,1 |
| 07.12.15 | Properties of gases, liquids and solids | 88,0 |
| 07.12.15 | Thermal movement of molecules | 70,6 |
| 07.12.15 | Internal energy | 81,1 |
| 07.12.15 | Ways to change internal energy | 66,2 |
| 07.12.15 | The law of conservation of energy in thermal processes | 58,4 |
| 07.12.15 | Evaporation and condensation | 68,7 |
| 07.12.15 | Specific heat of fusion | 19,3 |
| 14.12.15 | Electrifying bodies | 43,7 |
| 14.12.15 | Electric charge conservation law | 44,7 |
| 14.12.15 | Conductors and insulators | 31,8 |
| 14.12.15 | Average percentage of test completion |
Diagram 1
Average results of assignments for checked topics
Table 4 and Diagram 2 show the average results of the development of controlled activities by 8th grade students.
Table 4
| Code | Average% completion | |
| 9_1.1 | 44,4 | |
| 9_1.2 | 74,8 | |
| 9_1.3 | 34,5 | |
| 9_1.4 | 56,0 | |
| 9_2.3 | Ability to analyze the results of experimental studies, including those expressed in the form of a table or graph. | 58,5 |
| 9_2.4 | 54,9 | |
| 9_3 | Solving problems of various types and levels of complexity | 23,6 |
Diagram 2
Average results of assignments for the audited activities
Data analysis suggests that 8th grade students have mastered most of the tested physical concepts and physical quantities on this topic " Thermal phenomena»:
- the structure of solids, liquids and gases;
- thermal motion of molecules;
- internal energy and ways to change it.
The formation of such concepts as conductors and insulators, the interaction of permanent magnets was checked on the topics "Electrical and magnetic phenomena". The level of mastering these concepts turned out to be lower than planned.
The diagnostic results showed that the students had difficulty in analyzing the phenomenon of electrification. The tasks with a short answer turned out to be even more difficult.
The diagnostic work included tasks to check the development of experimental skills. New tasks for diagnostics in physics turned out to be problematic for describing a real electrical circuit from a photograph.
Examples of tasks
All the tasks of the diagnostic work, except for the last two tasks, did not require calculations, but checked the development of physical concepts and understanding of physical phenomena and laws.
The task was included in the diagnostic work basic level difficulties with a short answer (for compliance), which checks the formation of such concepts as a physical quantity and a physical phenomenon. Students successfully isolate physical phenomena from the list of examples given, but sometimes do not distinguish between physical quantities and units of measurement.
In the task given in example 1, two students (Jamilya and Andrei) attributed not “temperature” to physical quantity, but “degree Celsius”.
Example 1 (Timur chose the correct answer 34 - 33% of the tested, and the answer 24 was given by 67% of the students, i.e. two students:
Establish a correspondence between physical concepts and examples of these concepts: for each position from the first column, select the corresponding position from the second column, indicated by a number.
CONCEPTS EXAMPLES
A) physical quantity 1) thermometer
B) physical phenomenon 2) degree Celsius
3) temperature
4) melting
Write down the selected numbers in the table.
| AND | B |
Almost all tasks on the topic "Electrical and magnetic phenomena" showed a low percentage of completion. This is a rather alarming result, which can affect the success of studying the topic "Electromagnetic phenomena" in the 9th grade. Traditionally, students have difficulty completing assignments to describe the electrification process (example 2).
Example 2 (percentage of completion -33% - 1 student - Timur)
A positively charged glass rod was brought to the ball at the end of the rod of an uncharged electroscope, without touching it (see figure). Leaflets
the electroscope diverged at a certain angle. What happens when this happens
with an electroscope charge?
1) The electroscope will remain generally neutral, but the charges will be redistributed: there will be a lack of electrons on the leaves, and an excess of electrons at the upper end of the rod. (33% is the correct answer)
2) The electroscope will remain generally neutral, but the charges will be redistributed: there will be an excess of electrons on the leaves, and a lack of electrons at the upper end of the rod. (33%)
3) Both the leaves and the rod of the electroscope will acquire a negative charge (0%).
4) Both the leaves and the rod of the electroscope will acquire a positive charge. (33%)
The low percentage of completing tasks for electrification indicates that students have not formed a model of the structure of a metal conductor, the concept of free electrons. Moreover, as shown by the results of diagnostics, students do not distinguish between conductors and insulators (example 3).
Example 3 (percentage of completion - 33%)
The figure shows identical electroscopes connected by a rod. What material can this rod be made of?
1) only A (0%) 2) only B (67%) 3) both A and B (0%) 4) neither A nor B (33% is correct)
Eighth graders were unable to separate the materials into conductors and dielectrics according to the classic demonstration experiment with two electrometers. But it is with the help of this experiment that the concept of conductors and non-conductors of electricity is introduced in the 8th grade.
The lack of ideas about free charges makes it difficult for students to complete and explain the task on the law of conservation of electric charge (example 4).
Example 4 (percentage of completion - 33%)
One of two identical balls was given a charge of –10q, the other - a charge of + 2q. Then the balls were connected with a thin conductor. The charges of the balls after connection will become the same and equal
1) - 4q (33% - correct answer) 2) - 6q (0%) 3) - 12q (0%) 4) - 8q (67%)
It should be noted that the load of tasks with graphic information (for example, the inclusion of real experimental schemes or photographs in tasks) leads to a noticeable decrease in the percentage of tasks completed. So, students successfully answer questions about the interaction of the poles of permanent magnets (example 5), but have difficulty in determining the poles of two permanent magnets for the case when the interaction should be analyzed from a photograph of a real experiment (example 6). This indicates that the students did not observe the painting magnetic field strip magnet obtained with iron filings.
Example 5 (percentage of completion - 67%)
A permanent strip magnet was brought to the magnetic needle (the north pole is darkened in the figure), which can rotate around a vertical axis perpendicular to the plane of the figure. In this case, the hand 1) turns 180 ° (0%) 2) turns 90 ° clockwise (33%) 3) turns 90 ° counterclockwise (67% is the correct answer) 4) remains in the same position (0 %)
Example 6 (percentage of completion - 33%)
The figure shows a picture of the magnetic field lines, obtained using iron filings from two strip magnets. In this case, the magnetic needle turned as shown in the figure. Which poles of the strip magnets correspond to areas 1 and 2?
1) 1 - North Pole, 2 - South (0%) 2) 2 - North Pole, 1 - South (33%) 3) and 1, and 2 - North Pole (33% - correct answer) 4) and 1, and 2 to the south pole (33%)
The insufficient experimental experience of eighth-graders is also evidenced by the results of performing tasks for analyzing the correctness of turning on electrical devices (voltmeter and ammeter) from photographs electrical circuits... Only half of the students coped with the task that tests the ability to determine the purpose of a voltmeter in an electrical circuit (example 7). This task differentiates well among students with different levels of development. With the task of determining the correctness of connecting devices (example 8, table 6), all schoolchildren did not cope almost equally. More than half of the tested did not pay attention to the polarity 11 of switching on the devices.
Example 7 (percentage of completion - 50%)
The student assembled the electrical circuit (virtually) shown in the figure.
Which statement is correct?
1) The voltmeter is included in the electrical circuit with polarity reversal. (33%)
2) When the key is closed, the voltmeter will show the voltage across the resistor R2. (67% is the correct answer)
3) When the key is closed, the voltmeter will show the total electrical voltage across the resistors R1 and R2. (0%) 12
4) The ammeter is included in the electrical circuit with polarity reversal. (0%)
Example 8 (percentage of completion - 14%) To measure the current passing through the lamp and the voltage across the lamp, the student assembled the electrical circuit shown in the figure.
What devices (ammeter and (or) voltmeter) are included in the electrical circuit correctly?
1) ammeter only (33%)
2) only voltmeter (33%)
3) both ammeter and voltmeter (0%)
4) neither ammeter nor voltmeter (33% is the correct answer)
Table 7 presents data on the development of activities by students who received different marks.
Table 7
| Controlled activity | Average% of assignments completed by students | |||
| "2" | "3" | "4" | "5" | |
| Knowledge and understanding of the meaning of concepts | 33,3 | 33,3 | - | 33,3 |
| Knowledge and understanding of the meaning of physical quantities | 33,3 | 33,3 | 33,3 | - |
| Knowledge and understanding of the meaning of physical laws | 33,3 | 33,3 | 33,3 | - |
| Ability to describe and explain physical phenomena | - | 33,3 | 33,3 | 33,3 |
| Ability to analyze the results of experimental research. | - | 66,7 | - | 33,3 |
| Ability to use physical instruments and measuring instruments for straight and indirect measurements physical quantities | - | 66,7 | - | 33,3 |
| Decision simple tasks different types | 33,3 | 33,3 | 33,3 | - |
As can be seen from the above tables, the tasks of diagnostic work, both in content and in the types of activity being tested, differentiate well among students with different levels of development.
Description of the level of training of students who received different grades on testing
| Test Participant Categories | Level Description |
| Mark "5". points - 9-12 Percentage of students in this category - no Average percentage of assignments completed - 0 | Students who received for the test excellent markdemonstrate proficiency in sufficient high level all checked content items. Students in this category are fully proficient in all tested activities |
| Mark "4" points - 7-9 Students in this category - 33.3% Average percentage of tasks completed 67% | Timurhave shown possession of all controlled elements of containment (completion of tasks of the basic level above 65%), except for the following: - description of electrification of bodies; - application of the law of conservation of electric charge and the law of light reflection; - recognition by the experimental scheme of conductors and dielectrics. Timur revealed an insufficient level of mastering the skills to solve computational problems |
| Mark "3" points - 4-6 Students in this category - 33.3% Average percentage of tasks completed 39% | Jamilawith a satisfactory level of training, she demonstrated unsystematic physical knowledge, having completed only certain tasks of the basic level of complexity on the topics "Structure of matter" and "Thermal phenomena": - description of the properties of gases, liquids and solids; - understanding the dependence of internal energy on temperature. Of the monitored activities, the level of development was achieved only for tasks on the knowledge and description of individual physical quantities. |
| Mark "2". points - 0 - 3 Percentage of students in this category - 33.3% Average percentage of assignments completed 18% | Andreywith an unsatisfactory level of training showed a low level of mastering physical knowledge and skills. It lacks fully internalized controllable content elements and fully formed activities. He studies at our Center for the first year, the first quarter was ill for a long time. |
findings
1) 67% of 8th grade students have basic knowledge and skills in physics based on the results of diagnostics. At the same time, 33.3% of the tested (Timur) showed not bad (good ???) results.
2) The highest percentage of completion had the tasks on the topic "Heat phenomena", although this section was studied in the first half of the 8th grade. Tasks on topics from the sections "Electrical and Magnetic Phenomena" on average had a significantly lower percentage of completion.
3) Analysis of the results of diagnostic work indicates that the students have not sufficiently developed experimental skills, as well as the ability to apply physical laws when solving computational problems and analyzing physical processes.
The following results were obtained:
Timur and Jamilya have an average level of development of logical
thinking
Andrey has a low level of development logical thinking
Based on the results of the study, the following conclusions can be drawn and a number of common featurestypical for most adolescents with delay mental development:
Rapid fatigability, reduced performance due to the phenomena of cerebrasthenia arising in children, psychomotor disinhibition, excitability;
Lack of abstract thinking
Underdevelopment of spatial representations
- medium (low ???) level of cognitive activity;
Instability of attention, disturbances in the speed of switching attention, its volume is reduced;
Memory is limited in volume; short-term memory prevails over long-term memory, mechanical over logical memory;
Lack of sufficiently persistent interest in the proposed task;
insufficient purposefulness of activities; low activity, to comprehend the work as a whole, to understand the causes of mistakes;
Children's verbal reports on the actions performed are not accurate enough. It is sometimes easier for a teenager to follow instructions than to tell them what they have done.
A significant delay in the development of internal speech makes it difficult for children to form the ability to predict and self-regulate activities.
All of the above is undoubtedly the reasons for the difficulties that students with CRD experience in learning activities and necessitates special corrective work.
To activate the mental activity of adolescents with mental retardation, we use the technique of creating problem situations in physics lessons that correspond to individual characteristics this category of children.
Purpose of the work: revealing the assimilation by students of the mandatory minimum of knowledge and skills; to assess the knowledge, skills and abilities of students on the topics: mastery of basic concepts and laws; 1.Knowledge / understanding: physical quantities characterizing: - uniformly accelerated rectilinear motion. - kinematics of periodic motion. - amplitude, frequency, period of oscillation of the pendulum; - body impulse - vector of magnetic induction, Ampere force, magnetic flux 2. Knowledge of the law and its practical use: - be able to write down the equation of coordinates, the equation of speed; - Newton's second law; - the law of conservation of momentum - the law Universal gravitation; free fall of bodies; be able to write down: - the equation of speed; - Newton's second law in vector form and in projections on the X and Y axes; - to determine the momentum of the body if the body's speed and mass are known 3. To perceive, process, present educational information: - to be able to determine from the equation of motion its parameters, the nature of motion; - determine: movement; speed, time, acceleration. oscillation period, vector of magnetic induction, magnetic flux, Purpose of the work: revealing the mastery by students of the mandatory minimum of knowledge and skills; to assess the knowledge, skills and abilities of students on the topics: mastery of basic concepts and laws; 1.Knowledge / understanding: physical quantities that characterize: - uniformly accelerated rectilinear motion. - kinematics of periodic motion. - amplitude, frequency, period of oscillation of the pendulum; - body impulse - vector of magnetic induction, Ampere force, magnetic flux 2. Knowledge of the law and its practical use:
150,000 rubles prize fund 11 honorary documents Certificate of publication in the media
Option 1
Part 1
1 A car on a straight road begins to accelerate with an acceleration of 0.5 m / s2 from rest and after a certain period of time reaches a speed of 5 m / s. What is this period of time?
1) 0.1 s 2) 1 sec 3) 2.5 s 4) 10 sec
2 There are two absolutely resilient springs. A force of 6 N is applied to the first spring, and a force of 3 N to the second. Compare the stiffness k 1 the first spring with stiffness k 2 the second springs with the same elongation.
1) k 1 = k 2 2) k 1 = 2k 2 3) 2k 1 = k 2 4) k 1 = k 2
3 The two bodies are at the same height above the Earth's surface. Weight of one body m1twice the mass of another body m2... Potential energy relative to the Earth's surface
1) the first body is 2 times the potential energy of the second body
2) the second body is 2 times the potential energy of the first body
3) the first body is 4 times the potential energy of the second body
4) the second body is 4 times the potential energy of the first body
4 A car with a mass of 1 ton, moving at a speed of 20 m / s, starts to brake and stops after a while. What is the total force of resistance to motion if the car travels a distance of 50 m to a complete stop?
1) 400 N 2) 500 N 3) 4000 N 4) 8000 N
5 After hot water is poured into a cold glass, the internal energy
1) both water and glass decreased
2) both water and glass increased
3) glasses decreased, and water increased
4) glasses increased, and water decreased
6 The figure shows a graph of the dependence of the temperature of alcohol on time. Initially, alcohol was in a gaseous state. What point on the graph corresponds to the beginning of the alcohol condensation process?
1) AND 2) B 3) IN 4) D
7 What kind of heat transfer is mainly carried out when warming up by a fire?
1) thermal conductivity 2) convection 3) radiation 4) convection and heat conduction
8 It is necessary to experimentally find out whether the resistance force that prevents the movement of a body in air depends on the size of the body. Which of the following balls can be used?
1) A and B 2) A and B 3) A and D 4) C and D
Part 2
values \u200b\u200bdo not need to be written.
IN 1Into a vessel with cold water lowered a steel drill with a mass of 1 kg, heated to a temperature of 200 ° C. The temperature in the vessel was set at 50 ° C. How much heat did the water receive for heating? Disregard the energy losses for heating the vessel and the surrounding air. Specific heat of steel 460 J / (kg⋅ ° WITH). Give the answer in kilojoules.
IN 2A carriage weighing 20 kg, moving at a speed of 0.3 m / s, overtakes another carriage weighing 30 kg, moving in the same direction at a speed of 0.2 m / s, and engages with it. What is the speed of the bogies after hitching? Give the answer in m / s.
Part 3
C1 Two spirals of an electric stove of the same resistance are connected in parallel and connected to a network with a voltage of 220 V. What is the resistance of one spiral of a tile if water weighing 2 kg, poured into an aluminum pan weighing 200 g, boils after 37 seconds? The initial temperature of the water and the pot was 20 ° C. Disregard the energy losses for heating the ambient air. The specific heat capacity of water is 4200 J / (kg⋅ ° C), aluminum is 900 J / (kg⋅ ° C).
Entrance diagnostics in physics for 10th grade
Option 2
Part 1
For each of tasks 1 - 8, 4 answer options are given, of which only one is correct.
1 The car begins to accelerate on a straight road from rest with an acceleration of 0.5 m / s 2. What will the vehicle speed be in 10 seconds?
1) 0.05 m / s 2) 0.5 m / s 3) 5 m / s 4) 20 m / s
2 There are two absolutely resilient springs. Under the same force, the first spring lengthened by 6 cm and the second by 3 cm. Compare the stiffness k 1 first spring with stiffness k 2 second.
1) k 1 = k 2 2) 4 k 1 = k 2 3) 2k 1 = k 2 4) k 1 = 2k 2
3 The kinetic energy of a body with a mass of 100 g, sliding off an inclined plane, is 0.2 J. What is the height of the inclined plane? Friction is neglected.
1) 0.1 m 2) 0.2 m 3) 1m 4) 2 m
4 The body moves along the surface of the table under the action of a horizontal traction force of 0.2 N with an acceleration of 0.8 m / s 2. The friction force is 0.08 N. What is the mass of this body?
1) 0.15 kg 2) 0.33 kg 3) 1.5KG 4) 3.3 kg
5 When a liquid is converted into vapor, the size of the intermolecular gaps ...
1. does not change.
2. can both increase and decrease.
3. decreases.
4. increases.
6 The figure shows a graph of water temperature versus time. The initial water temperature is 50 ° C. What state is the water in at the moment of time τ 1?
1) only in gaseous
2) only in liquid
3) part of the water - in liquid state, and part of the water is in gaseous
4) part of water is in a liquid state, and part of water is in a crystalline
7 How can heat transfer be carried out between bodies separated by an airless space?
1) only by thermal conductivity
2) only by convection
3) only by radiation
4) in all three ways
8 It is necessary to establish experimentally whether the buoyancy force depends on the volume of a body immersed in a liquid. Which set of aluminum and copper metal cylinders can be used for this purpose?
1) only A 2) only B 3) A or B 4) A or B
Part 2
When completing assignments, the answer must be written as a number in the specified units. Physical units values \u200b\u200bdo not need to be written.
IN 1When cooled by 20 degrees, a tin body emits an amount of heat equal to 9200 J. What is the mass of this body? The specific heat capacity of tin is 230 J / (kg⋅ ° C). Give the answer in kg.
IN 2 A trolley weighing 20 kg, moving at a speed of 0.5 m / s, is coupled with another trolley weighing 30 kg, moving towards it at a speed of 0.2 m / s. What is the speed of the bogies after hitching when the bogies move together? Give the answer in m / s
Part 3
The task of part 3 should be given a detailed answer
C1Two spirals of an electric stove with a resistance of 10 ohms each are connected in parallel and connected to a network with a voltage of 220 V. Water weighing 1 kg, poured into an aluminum pan weighing 300 g, boiled after 37 seconds. What is the starting temperature of the water and pot? Disregard the energy losses for heating the ambient air. The specific heat capacity of water is 4200 J / (kg⋅ ° C), aluminum is 900 J / (kg⋅ ° C).
OPTION 1
A-1
The figure shows graphs of four state change processes constant mass ideal gas. Isochoric heating is a process
and
b
in
r
(1 point)
A-2
In the course of the experiment, the internal energy of the gas decreased by 40 kJ, and it performed work of 35 kJ. Consequently, as a result of heat exchange, the gas gave environment amount of heat equal to
75 kj
40 kj
35 kj
5 kj
(1 point)
A-3
The figure shows a graph of temperature dependence solid from the amount of heat given to them. Body weight 4 kg. What is the specific heat capacity of the substance of this body?
0.002 J / (kgK)
0.5 J / (kgK)
500 J / (kgK)
40000 J / (kgK)
(1 point)
A-4
The distance between point electric charges has doubled. The value of one of the charges was reduced by 2 times. Interaction force between charges
Decreased by 2 times
Decreased by 4 times
Decreased 8 times
Has not changed
(1 point)
A-5
In the process of electrification by friction of two bodies, a negative charge appeared on one of them. What charge did the second body receive?
Negative
Positive
Its charge hasn't changed
The answer depends on the substances from which the bodies are made
(1 point)
Part B
IN 1
A monatomic ideal gas does work A in an isothermal process gas \u003e 0. How do the volume, pressure and internal energy of this gas change in this process?
Will increase
Will decrease
Will not change
Volume
Pressure
Internal gas energy
(2 points)
IN 2
In a container with a capacity of 500 ml 3 contains 0.9 g of hydrogen (relative molecular weight 2) at a temperature of 17 0 C. Determine the gas pressure. The universal gas constant is 8.31
(2 points)
Task with a detailed answer (solve the problem)
S-1
The body falls freely from a height of 40 m from rest. At what point in the trajectory of its motion, the kinetic energy is three times the potential energy? (neglect air resistance)
(3 points)
Diagnostic work in physics grade 10
OPTION 2
Part A (multiple choice questions)
A-1
The figures show graphs of the dependence of the volume of 1 mole of ideal gas on temperature for various processes. Which graph corresponds to the isobaric process?
(1 point)
A-2
In a cylindrical vessel under the piston, there is an ideal gas, the pressure of which is 4 10 5 Pa and a temperature of 300 K. How to change the volume of the gas without changing its temperature so that the pressure increases to 0.8 10 6 Pa?
increase 2 times
increase by 4 times
reduce by 2 times
reduce by 4 times
(1 point)
A-3
What work does the gas do during the transition from state 1 to state 3?
10 kj
20 kj
30 kj
40 kj
(1 point)
A-4
How will the force of the Coulomb interaction of two point charges change if the distance between them is reduced by 3 times?
Will increase 3 times
Will increase 9 times
Will decrease by 3 times
Decrease 9 times
Will not change
(1 point)
A-5
Tension electrostatic fieldin which the charge wasq, increased by 2 times. How many times has the force acting on this charge changed?
Has not changed
Increased 4 times
Decreased by 4 times
Increased 2 times
(1 point)
Part B
Matching task
IN 1
Plasticine ball massm swoops inv onto the same ball at rest. After a completely inelastic collision, the balls move together. How will the impulse of the system of balls, the velocity of the first ball and its kinetic energy change as a result of the collision?
For each value, determine the corresponding nature of the change (insert the corresponding number in the table):
Increases, a boy weighing 50 kg jumps from the stern to the side opposite to the movement of the boat at a speed of 7 ... What is the speed of the boat after the boy's jump?
(3 points)
Keys to Diagnostic Work in Physics for Grade 10
Option 1 (part A)
Option 2 (part A)
3
4
4
3
1
3
2
Option 1 (part B)
Option 2 (part B)
123
2 , 1 MPa
Option 1 (part C)
Option 2 (part C)
Grading scale (Physics - 10)
Mark on a five-point scale
Mark "2"
Mark "3"
Mark "4"