The main goal of the mechanization of production processes is the replacement of manual means of labor by machines and mechanisms using various types of energy for their operation. The mechanization of production processes frees a person from performing difficult, time-consuming and tedious operations. Depending on the degree of equipment of production processes with technical means and the type of work, partial and full mechanization are distinguished.
Automation of production is a method of organizing production, in which the functions of management and control, previously performed by a person, are transferred to automatic devices. The goal is to increase productivity and improve working conditions, ensure high quality products, optimize the use of all production resources, which accelerates scientific and technological progress.
Mode of work and rest.
The working time regime should provide for the duration of the working week, work with irregular working hours for a certain category of workers, the duration of daily work, including part-time work; start and end time of work; time of breaks in work; number of shifts per day; alternation of working and non-working days;
Features of the regime of working time and rest time for transport workers, communications workers and others who have a special nature of work are determined in the manner established by the Government of the Russian Federation.
Rest time is the time during which the employee is free from the performance of labor duties and which he can use at his own discretion.
Types of rest time:
breaks during the working day;
Daily (between shifts) rest;
· Days off (weekly uninterrupted rest);
· Non-working holidays;
· Holidays.
20. Methods for the analysis of industrial injuries.
· Statistical method. The level of injury is estimated by this method through two indicators - the coefficient of frequency and the coefficient of severity.
group method. The investigation material is divided into groups, taking into account certain characteristics, such as profession, type and length of service, age of the victim, time of day and year, type of rolling stock, traumatic factor, nature of damage.
Topographic method. The causes of accidents are studied at the place of their occurrence.
Monographic method. An in-depth analysis of work-related injuries is carried out, the technological process, the operations performed, the workplace, sanitary and hygienic conditions, the main and auxiliary equipment, PPE, and the circumstances under which the accident occurred are studied in detail.
Extensive indicators. Characterizing the structure of morbidity, are calculated according to the number of days of disability for one of the types of disease or according to the number of cases of disability for one of the diseases.
The indicator of the duration of one case of the disease. A report on the causes of temporary disability is drawn up in accordance with the established form No. 16 - ext.
Organization of the workplace of a car mechanic.
Before starting work, it is necessary to put the workplace in order; check the operation of ventilation, the serviceability of the guards, the starting device of the machine, the correct direction of rotation of the motors, the lubrication of equipment components, the pressure of compressed air and steam, the operation of pneumatic valves, brakes and interlocks. Workplaces must be kept clean and tidy. Tools and workpieces should be located in strictly designated places, providing safe and economical methods of performing operations. Work must be carried out strictly in accordance with the technological documentation, rules and instructions for labor protection.
Responsible persons for fire safety.
the owners of the property;
· Heads of public authorities;
· Heads of local self-government bodies;
· Persons authorized to own, use or dispose of property, including heads of organizations;
Persons duly appointed responsible for ensuring fire safety;
· Officials within their competence.
Mechanization and automation of production processes is one of the main directions of technical progress. The purpose of mechanization and automation is to facilitate the work of a person, leaving the functions of maintenance and control to a person, to increase labor productivity and improve the quality of manufactured products.
Rice. 3.2. ASh-NYu-1 model manipulator used for mechanization of loading operations, including equipment loading
Mechanization- the direction of development of production, characterized by the use of machines and mechanisms that replace the muscular labor of the worker (Fig. 3.2).
According to the degree of technical perfection, mechanization is divided into the following types:
partial and small-scale mechanization, characterized by the use of the simplest mechanisms, most often mobile. Small-scale mechanization can cover parts of movements, leaving many types of work, operations, and processes non-mechanized. Small-scale mechanization mechanisms may include trolleys, simple lifting equipment, etc.;
full, or complex mechanization, includes the mechanization of all basic, auxiliary, installation and transport operations. This type of mechanization
characterized by the use of fairly complex technological and handling equipment.
The highest level of mechanization is automation. Automation means the use of machines, instruments, devices, devices that allow production processes to be carried out without the direct participation of a person, but only under his control. Automation of production processes is inevitably associated with the solution of management processes, which must also be automated. The branch of science and technology that solves control systems for automatic equipment is called automation. Automation is based on the management, control, collection and processing of information about the automatic process with the help of technical means - special instruments and devices. The automated control system (ACS) is based on the use of modern electronic computers and electronic mathematical methods in production management and is designed to increase its productivity.
Automation production processes are also divided into two parts:
partial automation, covers part of the operations performed, provided that the remaining operations are performed by a person. As a rule, a direct impact on the product, i.e., processing, is automatically performed, and the loading operations of the workpieces and the re-enabling of the equipment are performed by a person. Such equipment is called semi-automatic;
full or complex automation, characterized by the automatic execution of all operations, including boot operations. A person only fills the loading devices with workpieces, turns on the machine, controls its actions, carrying out adjustments, tool changes and waste disposal. Such equipment is called automatic. Depending on the volume of introduction of automatic equipment, automatic lines, an automatic section, a workshop and a plant are distinguished.
As practice has shown, ordinary automation schemes and complex automation are effectively used only in large-scale and mass production. In multi-product production, where frequent changeover of the flow is required, ordinary automation schemes are of little use. Equipment equipped with stationary automation systems does not allow switching to manual control. The usual automation scheme implies the use of loading devices (slips, trays, hoppers, feeders, etc.) and processing equipment adapted to perform automatic operations. Processed products are removed using a device for receiving processed products (slides, trays, magazines, etc.).
Auto-operators and mechanical hands, long used in ordinary automation schemes, served as prototypes for a new kind of automation. A new type of automation using industrial robots (IR) allows you to solve problems that cannot be solved using conventional automation schemes. Industrial robots, as conceived by their developers, are designed to replace humans in hard and tedious jobs that are hazardous to health. They are based on modeling the motor and control functions of a person.
Industrial robots solve complex product assembly processes, welding, painting and other complex technological operations, as well as loading, transporting and storing parts. The new type of automation has a number of properties that qualitatively distinguish it from other types of properties, giving PR significant advantages over ordinary schemes:
high manipulation properties, i.e., the ability to move parts along complex spatial trajectories;
own drive system;
program control system;
autonomy of PR, i.e., their non-integration into technological equipment;
universality, i.e., the ability to move products of various types in space;
compatibility with a fairly large number of types of process equipment;
adaptability to various types of work and products replacing each other;
the ability to turn off the PR and switch to manual control of the equipment.
Depending on the participation of a person in the processes of controlling robots, they are divided into biotechnical, autonomous.
Biotechnical are remote copying robots controlled by a human. The robot can be controlled from the remote control using systems of handles, levers, keys, buttons, or by “putting” special devices on the arms, legs or body of a person. These devices serve to reproduce human movements at a distance with the necessary increase in effort. Such robots are called exoskeleton robots. Robots of semi-automatic action also belong to biotechnical robots.
Autonomous robots work automatically with the help of program control.
Over the relatively long history of the development of robotics, several generations of robots have already been created.
First generation robots(software robots) are characterized by a rigid program of actions and elementary feedback. These usually include industrial robots (IR). At present, this system of robots is the most developed. The first generation PRs are divided into universal, target PRs of the lifting and transport group, target robots of the production group. In addition, robots are divided into standard size rows, into rows according to maximum productivity, according to the radius of service, according to the number of degrees of freedom, etc.
Second generation robots(sentient robots) have coordination of movement with perception. The control program for these robots is carried out using a computer.
To third generation robots includes robots with artificial intelligence. These robots create conditions for replacing a person in the field of skilled labor, have the ability to adapt in the production process. Robots of the third generation are able to understand the language, can conduct a dialogue with a person, plan behavior, etc.
Carrying out complex automation of technological processes of sites, workshops and factories, they create robotic technological complexes (RTC). robotic technological complex is a set of technological equipment and industrial robots. The RTK is placed on a certain area and is intended for one or more operations in automatic mode. The equipment included in the RTK is divided into processing equipment, servicing equipment and equipment for monitoring and control. The processing equipment includes the main technological equipment upgraded to work with industrial robots. The service equipment contains a device for placing parts at the entrance to the RTK, interoperational transporting h storage devices, devices for receiving processed products, as well as industrial robots (Fig. 3.3). Monitoring and control equipment ensures the mode of operation of the RTK and the quality of products.
Pic. 3.3. Floor robot with horizontal retractable arm and cantilever lifting mechanism PR-4
An increase in the efficiency of the use of industrial robots is facilitated by a rational reduction in the range of PR and an improvement in their adaptability (adaptability). This is achieved by PR typing. A comprehensive analysis of production is carried out, a grouping of robotic objects and the establishment of types and main parameters of the PR. Typification of PR is the basis for the development of their unification, which should be aimed at ensuring the possibility of creating robots by aggregation. To ensure the principle of aggregation, standardization is carried out: 1) connecting dimensions of drives, transmission mechanisms and feedback sensors; 2) rows of output parameters of drives (powers, speeds, etc.); 3) methods of communication of program control devices with executive and measuring devices.
The result of work on the unification of PR should be the creation of their optimal type and a system of modular construction. The aggregate-modular system for building industrial robots is a set of methods and tools that ensure the construction of different sizes of PR kz of a limited number of unified nodes (modules and assemblies). It allows the use of a minimum number of mass-produced functional units, which are selected from special industrial catalogs. This makes it possible in multi-product production to quickly rebuild the robotic systems of machines for the production of new products. On the basis of PR with aggregate-modular construction, flexible automated production (FAP) is based.
Planning for the introduction of mechanized and automated equipment is associated with an analysis of production. Analysis of production is reduced to identifying a number of conditions that contribute to the use of this equipment. The analysis is not subject to production associated with the use of heavy manual labor. The mechanization and automation of heavy manual labor is a paramount task and does not depend on the results of economic calculation.
The design of mechanization and automation of technological processes must begin with an analysis of the existing production. During the analysis, those features and specific differences are clarified and specified, on the basis of which one or another type of equipment is selected. The pre-design stage of the development of mechanization and automation of production processes includes the solution of a number of issues.
1. The analysis of the product release program includes the study of: the annual release program of the product, stability and release prospects; level of unification and standardization; specialization and centralization of production; the rhythm of production; cargo turnover (cargo turnover is the total mass of incoming and outgoing cargo - for loading operations). It must be remembered that the effectiveness of mechanization and automation of the process to a large extent depends on the product release program. Mechanization and automation devices in mass and small-scale production will differ significantly.
2. The analysis of the technological process of manufacturing products subject to mechanization and automation includes: determining the suitability of the technological process for mechanization and automation; identification of shortcomings of the current technological process; determination of the labor intensity of the main and auxiliary operations;
comparison of existing manufacturing modes with modes recommended in reference books; analysis of the application of group technology; division of the technological process into classes.
The first main class includes processes that require the orientation of the workpiece (part) and are characterized by the presence of a machined tool. These processes are characteristic of the main range of products that are manufactured by cutting, pressure or assembled, controlled, etc. The second main class includes processes that do not require orientation of the workpiece (part), they use a working environment instead of a processing tool. These include heat treatment, tumbling, washing, drying, etc.
The first transitional class includes processes that require the orientation of the workpiece (part), but there is no tool, and its role is played by the working environment; deposition of local coatings, hardness control by magnetization, etc. The second transitional class includes processes that do not require the orientation of the workpiece (part), but they involve a machining tool; production of parts by powder metallurgy, production of metal-ceramic and ceramic parts, etc.
3. Analysis of the design of the product, while establishing the clarity of the processing of the product and the completeness of the technical requirements for the manufactured part; the shape, dimensions, materials, mass of the product are investigated and suitability for one or another type of mechanization and automation is established.
4. Selection of information on various types of mechanization and automation. Before starting work, all methods and technological schemes, as well as equipment, instruments and tools mastered by the industry, must be known. Before making a decision, a search is made for information on the production of similar products in the country and abroad.
5. Economic calculation of the effectiveness of the proposed mechanization and automation of production.
6. Development and approval of recommendations for changing existing production conditions. Recommendations are developed on the basis of the analysis carried out and may include: unification, i.e. reduction to one standard size of products with similar designs; change in the sequence of technological operations or the use of a completely new progressive technological process; the use of a group technological process of products similar in design; application of a new type of product blank; clarification and, if necessary, change of the technical requirements of the drawing; change in the shape and size of the product; change in product material.
7. Making a decision on the use of a certain principle of mechanization and automation and drawing up a technical assignment for development.
Mechanization and automation of production processes- This is a set of measures that provide for the widespread replacement of manual operations by machines and mechanisms, the introduction of automatic machine tools, individual lines and industries.
Mechanization of production processes means the replacement of manual labor by machines, mechanisms and other equipment.
The mechanization of production is constantly developing and improving, passing from lower to higher forms: from manual labor to partial, small and complex mechanization and further to the highest form of mechanization - automation.
In mechanized production, a significant part of labor operations is performed by machines and mechanisms, a smaller part - manually. it partial (non-complex) mechanization, in which there may be separate weakly mechanized links.
Integrated mechanization- this is a way to perform the entire complex of works included in a given production cycle, machines and mechanisms.
The highest degree of mechanization is automation of production processes, which allows you to carry out the entire cycle of work without the direct participation of a person in it, only under his control.
Automation is a new type of production, which is prepared by the cumulative development of science and technology, primarily by transferring production to an electronic basis, using electronics and new advanced technical means. The need for automation of production is caused by the inability of human organs to control complex technological processes with the necessary speed and accuracy. Huge energy capacities, high speeds, ultra-high and ultra-low temperature conditions turned out to be subject only to automatic control and management.
At present, with a high level of mechanization of the main production processes (80%) in most industries, auxiliary processes are still insufficiently mechanized (25-40), many works are performed manually. The largest number of auxiliary workers is used in transport and the movement of goods, in loading and unloading operations. If, however, we take into account that the labor productivity of one such worker is almost 20 times lower than that of a worker employed in complex-mechanized areas, then the acuteness of the problem of further mechanization of auxiliary work becomes obvious. In addition, it is necessary to take into account the fact that the mechanization of auxiliary work in industry is 3 times cheaper than the main one.
But the main and most important form is production automation. At present, computing machines are becoming more and more decisive in all areas of science and technology. In the future, these machines will become the basis of production automation and will control automation.
The creation of new automatic technology will mean a broad transition from three-link machines (working machine - transmission - engine) to four-link machine systems. The fourth link is cybernetic devices, with the help of which huge powers are controlled.
The main stages of automation of production are: semiautomatic devices, automatic lines, automatic lines, sections - and workshops - automatic machines, factories - and automatic factories. The first stage, which is a transitional form from simple to automatic machines, are semi-automatic machines. The principal feature of the machines of this group is that a number of functions previously performed by a person are transferred to the machine, but certain operations are still retained by the worker, which are usually difficult to automate. The highest step is the creation of factories - and factories - automatic machines, i.e. fully automated enterprises.
The main indicators characterizing level of mechanization and automation, are:
The coefficient of mechanization of production
where K mp - coefficient of mechanization of production;
V M - the volume of products produced with the help of machines and mechanisms;
V total - the total volume of manufactured products at the enterprise;
The coefficient of mechanization (automation) of labor (K ^.t)
where N M is the number of workers employed in mechanized (automated) work, people;
Np is the number of workers performing manual operations;
Coefficient of mechanization (automation) of works (Cr)
where V M is the amount of work performed in a mechanized (automated) way;
V total - the total amount of work;
The level of automation Y and in practice is often determined from the expression
where K a - the number of automatic equipment in pieces or its cost in rubles;
K is the quantity or cost of non-automatic equipment.
It should be noted that this indicator of the level of automation, determined on the basis of a comparison of the used automatic and non-automatic equipment, does not quite accurately characterize the level of automation in the enterprise.
To a certain extent, the level of mechanization of production characterizes such an indicator as the technical equipment of labor (Kt.v.) which is determined from the expression
where Fa - the average annual cost of the active part of fixed production assets;
N - the average number of employees of the enterprise or workers.
The economic and social significance of mechanization and automation of production lies in the fact that they make it possible to replace manual labor, especially heavy labor, with machines and automatic machines, increase labor productivity and, on this basis, ensure real or conditional release of workers, improve the quality of products, reduce labor intensity and production costs. , increase the volume of production and thereby provide the enterprise with higher financial results, which makes it possible to improve the well-being of workers and their families.
I: ((1)) Nuclear reactions; t=90; K=C; M=30;
S: Define second product X in a nuclear reaction:+ 
P+X. -: alpha particle +: neutron -: proton
-: electron
I: ((2)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: When bombarded by -particles (helium nucleus 
) aluminum nuclei 
a new nucleus of an unknown element X is formed and a neutron 
. The serial number of the element X in the periodic table is equal to:
I: ((3)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: Power of nuclear power plant Р=7* 10 3 kW. Power plant efficiency=20%. Nuclear reactor runs on uranium 
. With each act of decay, energy W = 200 MeV is released. Daily consumption of uranium fuel m equals:
I: ((4)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: When bombarded with nitrogen isotope nuclei 
neutrons produce an isotope of boron 
Q. What other particle is produced in this reaction?
+: - particle
-: 2 neutrons
-: 2 protons
I: ((5)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: During decay, the charge of the radioactive nucleus decreases by:
+: 3.210 -19 C
-: 1.610 -19 C
-: 6.410 -19 C
-: 2.410 -19 C
I: ((6)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Binding energy of hydrogen isotope nucleus 
equal to E St = 8.5 MeV. The specific energy E sp of the bond of the nucleus and the mass defect M of the nucleus, respectively, are equal to:
-: E sp \u003d 2.0 MeV and M \u003d 7.3 10 -29 kg
-: E sp \u003d 2.2 MeV and M \u003d 4.6 10 -30 kg
-: E sp \u003d 2.4 MeV and M \u003d 1.2 10 -31 kg
+: E sp \u003d 2.8 MeV and M \u003d 1.5 10 -27 kg
I: ((7)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: During a nuclear reaction, the nucleus absorbs an alpha particle and emits a neutron. As a result, the nuclear charge:
+: increase by 2 units
-: increase by 3 units
-: decrease by 2 units
-: decrease by 3 units
I: ((8)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: In the course of a nuclear reaction, the nucleus absorbs 2 protons and emits an α-particle. As a result, the nuclear charge:
+: will not change
-: increase by 2 units
-: decrease by 2 units
-: increase by 4 units
I: ((9)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: A nuclear transformation takes place in the reactor: 
. The missing piece is:
+: neutron
-: electron
-: alpha particle
I: ((10)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: When studying the transformation of a radioactive substance in two experiments with different masses of the substance, it was found that the number N of particles formed per unit time during radioactive decay decreases with time in accordance with the graphs (see Fig.). To explain the differences between the experimental curves in these experiments, two hypotheses were formulated:
A) gross errors in the second experiment,
B) the probabilistic nature of the law of radioactive decay.
Which of the hypotheses is correct?
+: only B
-: only A
- neither A nor B
I: ((11)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: What is the binding energy of the sodium isotope nucleus 
? The mass of the nucleus is 22.9898 amu. Round your answer to the nearest integer.
+: 310 –11 J
-: 310 11 J
-: 210 –14 J
I: ((12)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Out of 20 identical radioactive nuclei, 10 nuclei experienced radioactive decay in 1 minute. In the next minute, they will experience decay:
+: 0 to 10 cores
-: 0 to 5 cores
I: ((13)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Thorium 
th can turn into radium 
Ra as a result:
+: one -decay
-: one -decay
-: one - and one -decay
-: emission of -quantum
I: ((14)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: What kind of nuclear reaction can be used to produce a fission chain reaction?
+: 
+ 
n 4 
n+ 
Mo+ 
Xe
-: 
C 
Li+ 
Li
-: 
Th+ 
n 
In + 
Nb
-: 
Cm 
Tc+ 
I
I: (15)) Nuclear reactions; t=30; K=A; M=30;
Q: Mark the correct answers:
S: Beta radiation is:
+: electron flow
-: flow of helium nuclei
-: proton flux
-: electromagnetic waves
I: ((16)) Nuclear reactions; t=120; K=B; M=100;
Q: Mark the correct answers:
S: Fusion reaction 
goes with the release of energy, while
A) the sum of the charges of the particles - the products of the reaction - is exactly equal to the sum of the charges of the original nuclei .
B) the sum of the masses of the particles - the products of the reaction - is exactly equal to the sum of the masses of the original nuclei.
Are the above statements true?
+: only A is true
-: only B is correct
- both A and B are correct
-neither A nor B are correct
I: ((17)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: How many - and -decays must occur in the radioactive decay of the uranium nucleus 
and its final transformation into a lead nucleus 
?
+: 10 - and 10-decays
-: 10 - and 8-decays
-: 8 - and 10-decays
-: 10 -and 9-decays
I: ((18)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: What is the number of protons and neutrons in the nucleus of calcium 
Ca?
I: ((19)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Polonium 
turns into bismuth 
as a result of radioactive decays:
+: one and one
-: one and two
-: two and one
-: two and two
I: ((20)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: As a result of a series of radioactive decays, uranium 92 238 U turns into lead
82 206 Pb. What number of α- and β-decays does he experience in this case?
+: 8 - and 6-decays
-: 10 - and 8-decays
-: 8 - and 10-decays
-: 10 -and 9-decays
I: ((21)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: Radioactive lead, having experienced one α-decay and two β-decays, turned into an isotope:
-: bismuth
+: lead
-: polonium
-: thallium
I: ((22)) Nuclear reactions; t=150; K=C; M=100;
Q: Mark the correct answers:
S: The half-life of the nuclei of radium atoms is 1620 years. This means that in a sample containing a large number of radium atoms:
-: In 1620 years, the atomic number of each atom of radium will be halved
-: One radium nucleus decays every 1620 years
+: Half of the original radium nuclei decay in 1620 years
-: all initially available radium nuclei will decay after 3240 years
I: ((23)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: What charge Z and mass number A will the nucleus of an element produced from the nucleus of an isotope after one α-decay and one electron β-decay have?
I: ((24)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: A graph of the number of undecayed erbium nuclei versus time is given.
What is the half-life of this isotope?
-: 25 hours
+: 50 hours
-: 100 hours
-: 200 hours
I: ((25)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: The figure shows some of the lowest energy levels of the hydrogen atom.
Can an atom in the E 1 state absorb a photon with an energy of 3.4 eV?
-: Yes, while the atom goes into the state E 2
-: Yes, while the atom goes into the state E 3
-: Yes, while the atom is ionized, decaying into a proton and an electron
+: no, the energy of the photon is not enough for the transition of the atom to an excited state
I: ((26)) Nuclear reactions; t=90; K=C; M=30;
Q: Mark the correct answers:
S: What proportion of radioactive nuclei will decay after a time interval equal to two half-lives?
I: ((27)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Radioactive polonium, having experienced one α-decay and two β-decays, turned into an isotope:
-: lead
+: polonium
-: bismuth
-: thallium
I: ((28)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: It is known that 
radiation is accompanied by the emission of neutrinos 
. With this in mind, the reaction 
decay can be written like this: 
. What can be said about the mass and charge of a neutrino?
-: mass - 0, charge negative
+: charge - 0, neutrino mass does not exceed the difference between the masses of a neutron and a proton with the mass of an electron
-: mass - 0, positive charge
-: mass - 0, the mass of the neutrino exceeds the difference between the masses of the neutron and proton with the mass of the electron
I: ((329) Nuclear reactions; t=30; K=A; M=30;
Q: Mark the correct answers:
S: Which of the radiations has the least penetrating power?
+:
radiation
-:
radiation
-:
radiation
-: the penetrating power of all radiations is approximately the same
I: ((30)) Nuclear reactions; t=90; K=B; M=60;
Q: Mark the correct answers:
S: In the above formula for a nuclear reaction, cross out the unnecessary term: 
?
-:
+:
-:
-:
I: ((31)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: There are several 
and 
-decays. How many decays are there in this chain?
I: ((32)) nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: If the initial number of polonium atoms 
10 6 and its half-life is 138 days, then the number of decayed atoms per day is equal to:
+:
-:
I: ((33)) Nuclear reactions; t=90; K=B; M=60;
Q: Mark the correct answers:
S: The figure shows the diagrams of four atoms. Black dots indicate electrons. Atom 
corresponds to the scheme:
+:
-:
I: ((34)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: Determine the half-life T 1/2 of a certain radioactive isotope, if its activity for t=5 days has decreased by n=2.2 times.
I: ((35)) Nuclear reactions; t=120; K=C; M=60;
Q: Mark the correct answers:
S: In the chain of radioactive transformation of an element with serial number 92 and atomic mass 235 into an element with number 82 and mass 207 (uranium to lead) contains several 
and 
decays. How many decays are there in this chain?
I: ((36)) Nuclear reactions; t=60; K=B; M=30;
Q: Mark the correct answers:
S: Where in the periodic system of elements does an atom move, the nucleus of which undergoes γ-decay?
-: to the left by 1 cell;
-: to the right by 1 cell;
+: does not move anywhere;
-: 2 cells to the left
I: ((37)) Nuclear physics; t=60; K=B; M=30;
Q: Mark the correct answers:
S: Where does an atom move in the Periodic system of elements, the nucleus of which undergoes one β-decay?
+: Left one cell
-: Right one cell
- will not move anywhere
-: down one cell
I: ((38)) Nuclear reactions; t=30; K=A; M=30;
Q: Mark the correct answers:
S: What is called α-decay?
-: Any reactions involving nuclei
-: radioactive transformations of nuclei with the emission of α-particles
+: nuclear decay 
He
- nuclear reactions that occur only due to strong interactions
I: ((39)) Nuclear reactions; t=30; K=A; M=30;
Q: Mark the correct answers:
S: Of the two isotopes, the one with the most stability is:
+: greater resting energy
-: less binding energy
-: high binding energy
-: both binding energy and specific binding energy are less
I: ((40)) Nuclear reactions; t=60; K=B; M=30;
Q: Mark the correct answers:
S: The law of radioactive decay is written as:
-: λ= T 1/2
+: N=N 0е -λ t
I: ((41))Nuclear reactions;t=120;K=C;M=60
Q: Mark the correct answers:
S: The half-life of radon is 3.8 days. After what time will the mass of radon decrease by 64 times?
I: ((42))Nuclear reactions;t=120;K=C;M=60
Q: Mark the correct answers:
S: The half-life of the mercury isotope Hg is 20 min. If initially there were 40 g of this isotope in the vessel, then how much will it be approximately after 1 hour?
I: ((43))Nuclear reactions;t=90;K=C;M=30;
Q: Mark the correct answers:
S: What is the mass number of the nucleus X in the reaction 
U+ 
N→X+4n?
