Английский язык. ЦУО, 2кр. Профили: «Электрооборудование и электротехнологии», «Электроснабжение», «Энергообеспечение предприятий»
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| Вариант 1 | Вариант 2 | Вариант 3 | Вариант 4 | Вариант 5 |
ВАРИАНТ 1
I. Перепишите следующие предложения, подчеркните в каждом из них глагол-сказуемое и определите его видо-временную форму и залог. Переведите предложения на русский язык.
1. Much work had been done for improving soil fertility on this farm.
2. Modern agriculture is developing in close contact with science and new technologies.
3. Our industry will increase the output of faster and more powerful tractors.
4. The driver usually increases speed gradually.
5. Some cities are so noisy and polluted that in many places vehicles have been banned in the city centre.
6. I was watching TV from 7 to 9 p. m. yesterday.
7. Ann had done her homework before her parents came.
II. В следующих предложениях подчеркните Participle I и Participle II установите функции каждого из них, т.е. укажите, является ли оно определением, обстоятельством или частью глагола-сказуемого. Переведите предложения на русский язык.
1. A letter sent from St. Petersburg today will be in Moscow tomorrow.
2. When sending the telegram, she forgot to write her name.
3. A fish taken out of the water cannot live.
4. They will be working at that time tomorrow.
5. He had translated the text before I came.
III. Работа с текстом:
a) переведите текст письменно на русский язык;
b) составьте глоссарий (13-15 слов или словосочетаний терминологического характера с их значениями);
с) письменно ответьте на вопросы.
POLARITY
All matter is basically composed of two types of electricity: positive particles and negative particles. The negative particles are relatively light in weight and in constant motion. These orbiting particles exhibit equal and opposite electrical characteristics to the heavier particles within the nucleus. When an atom has the same number of electrons as it has protons, it exalts no outward electrical properties. This is because the positive and negative charges are exactly balanced. Such an atom is electrically stable and is said to be neutral.
When an atom takes on an excess of electrons, it exhibits outward characteristics similar to the electron. It takes an overall negative property. This condition is called a negative change, and such changed atom is not electrically stable. A charged atom is called an ion, and if the charge is negative, it is called a negative ion.
An atom which has less than its normal quota of electrons, displays a positive polarity similar to that of the proton due to the fact that it has more positive protons than it has negative electrons. This type of atom is said to assume a positive electrical charge. Such an atom is known as a positive ion while it is in this electrically unstable condition. These charges of atoms are the simplest examples of static electricity. We stated that atoms are influenced to accept or give up electrons.
As the name dynamic electricity indicates, this is electricity in motion.The heart of the matter is electron movement. In electrical system, electrical pressure is needed. To maintain this pressure, a device that will move electrons in a way similar to that in which the pump moves water is necessary. The most familiar is the storage battery.
Answer the questions.
1.What two types of electricity do you know?
2. Are positive and negative charges balanced?
3. What happens when an atom takes on an excess of electrons?
4. When does an atom display a positive polarity?
5. What is dinamic electricity?
ВАРИАНТ 2
I. Перепишите следующие предложения, подчеркните в каждом из них глагол-сказуемое и определите его видо-временную форму и залог. Переведите предложения на русский язык.
1. Much work had been done for improving soil fertility on this farm.
2. Modern agriculture is developing in close contact with science and new technologies.
3. Our industry will increase the output of faster and more powerful tractors.
4. The driver usually increases speed gradually.
5. Some cities are so noisy and polluted that in many places vehicles have been banned in the city centre.
6. I was watching TV from 7 to 9 p. m. yesterday.
7. Ann had done her homework before her parents came.
II. В следующих предложениях подчеркните Participle I и Participle II установите функции каждого из них, т.е. укажите, является ли оно определением, обстоятельством или частью глагола-сказуемого. Переведите предложения на русский язык.
1. A letter sent from St. Petersburg today will be in Moscow tomorrow.
2. When sending the telegram, she forgot to write her name.
3. A fish taken out of the water cannot live.
4. They will be working at that time tomorrow.
5. He had translated the text before I came.
III. Работа с текстом:
a) переведите текст письменно на русский язык;
b) составьте глоссарий (13-15 слов или словосочетаний терминологического характера с их значениями);
с) письменно ответьте на вопросы.
THE NATURE OF ELECTRICITY
Practical electricity is produced by small atomic particles known as electrons. It is the movement of these particles which produce the effects of heat and light.
The pressure that forces these atomic particles to move, the effects they encounter opposition and how these forces are controlled are some of the principles of electricity.
Accepted atomic theory states that all matter is electrical in structure. Any object is largely composed of a combination of positive and negative particles of electricity. Electric current will pass through a wire, a body, or along a stream of water. It can be established in some substances more readily than in others, that all matter is composed of electric particles despite some basic differences in materials. The science of electricity then must begin with a study of the structure of matter.
Matter is defined as any substance which has mass (or weight) and occupies space. This definition should be broad enough to cover all physical objects in the universe. Wood, water, iron, and paper are some examples of matter. Energy is closely related to, but not to be confused with, matter. Energy does not have mass, and it does not occupy space. Heat and light are examples of energy.
The smallest particle of matter which can be recognized as an original substance was thought to be a unit called the atom. Recently scientists have found particles even smaller than atoms, but our theories are still based on the atom. The atom consists of a nucleus and a cloud of electrons. It is generally agreed that the electrons are small particles of electricity, which are negative in nature. These particles orbit the nucleus in much the same fashion that planets orbit a sun.
Answer the questions.
1.What produces the effect of heat and light?
2. What are some of the principles of electricity?
3. What does accepted atomic theory state?
4. What are some examples of matter?
5. Does atom consist of a nucleus and a cloud of electrons?
ВАРИАНТ 3
I. Перепишите следующие предложения, подчеркните в каждом из них глагол-сказуемое и определите его видо-временную форму и залог. Переведите предложения на русский язык.
1. Much work had been done for improving soil fertility on this farm.
2. Modern agriculture is developing in close contact with science and new technologies.
3. Our industry will increase the output of faster and more powerful tractors.
4. The driver usually increases speed gradually.
5. Some cities are so noisy and polluted that in many places vehicles have been banned in the city centre.
6. I was watching TV from 7 to 9 p. m. yesterday.
7. Ann had done her homework before her parents came.
II. В следующих предложениях подчеркните Participle I и Participle II установите функции каждого из них, т.е. укажите, является ли оно определением, обстоятельством или частью глагола-сказуемого. Переведите предложения на русский язык.
1. A letter sent from St. Petersburg today will be in Moscow tomorrow.
2. When sending the telegram, she forgot to write her name.
3. A fish taken out of the water cannot live.
4. They will be working at that time tomorrow.
5. He had translated the text before I came.
III. Работа с текстом:
a) переведите текст письменно на русский язык;
b) составьте глоссарий (13-15 слов или словосочетаний терминологического характера с их значениями);
с) письменно ответьте на вопросы.
EFFECTS PRODUCED BY A CURRENT
The current flow is detected and measured by any of the effects that it produces. There are three important effects accompanying the motion of electric charges: the heating, the magnetic, and chemical effects, the latter is manifested under special conditions.
The production of heat is perhaps the most familiar among the principal effects of an electric current. The heating effect of the current is found to occur in the electric circuit itself. It is detected owing to an increase in the temperature of the circuit. This effect represents a continual transformation of electric energy into heat. For instance, the current which flows through the filament of an incandescent lamp heats that filament to a high temperature.
The heat produced per second depends both upon the resistance of the conductor and upon the amount of current carried through it. The thinner the wire is, the greater the developed heat is. On the contrary, the larger the wire is, the more negligible the heat produced is. Heat is greatly desirable at times but at other times it represents a waste of useful energy. It is this waste that is generally called "heat loss" for it serves no useful purposes and decreases efficiency.
The heat developed in the electric circuit is of great practical importance for heating, lighting and other purposes. Owing to it people are provided with a large number of appliances, such as: electric lamps that light our homes, streets and factories, electrical heaters that are widely used to meet industrial requirements, and a hundred and one other necessary and irreplaceable things which have been serving mankind for so many years.
The electric current can manifest itself in some other way. It is the motion of the electric charges that produces the magnetic forces. A conductor of any kind carrying an electric current, a magnetic field is set up about that conductor. This effect exists always whenever an electric current flows, although in many cases it is so weak that one neglects it in dealing with the circuit. An electric charge at rest does not manifest any magnetic effect. The use of such a machine as the electric motor has become possible owing to the electromagnetic effect.
The last effect to be considered is the chemical one. The chemical effect is known to occur when an electric current flows through a liquid. Thanks to it a metal can be transferred from one part of the liquid to another. It may also effect chemical changes in the part of the circuit comprising the liquid and the two electrodes which are found in this liquid. Any of the above mentioned effects may be used for detecting and measuring current.
Answer the questions.
1. What are three important effects accompanying the motion of electric charges?
2. How is the heating effect of the current detected?
3. What is heat loss?
4. What is the other way of the electric current manifestation?
5. When does the chemical effect of the electric current occur?
ВАРИАНТ 4
I. Перепишите следующие предложения, подчеркните в каждом из них глагол-сказуемое и определите его видо-временную форму и залог. Переведите предложения на русский язык.
1. Much work had been done for improving soil fertility on this farm.
2. Modern agriculture is developing in close contact with science and new technologies.
3. Our industry will increase the output of faster and more powerful tractors.
4. The driver usually increases speed gradually.
5. Some cities are so noisy and polluted that in many places vehicles have been banned in the city centre.
6. I was watching TV from 7 to 9 p. m. yesterday.
7. Ann had done her homework before her parents came.
II. В следующих предложениях подчеркните Participle I и Participle II установите функции каждого из них, т.е. укажите, является ли оно определением, обстоятельством или частью глагола-сказуемого. Переведите предложения на русский язык.
1. A letter sent from St. Petersburg today will be in Moscow tomorrow.
2. When sending the telegram, she forgot to write her name.
3. A fish taken out of the water cannot live.
4. They will be working at that time tomorrow.
5. He had translated the text before I came.
III. Работа с текстом:
a) переведите текст письменно на русский язык;
b) составьте глоссарий (13-15 слов или словосочетаний терминологического характера с их значениями);
с) письменно ответьте на вопросы.
SEMICONDUCTORS
There are materials that really occupy a place between the conductors of the electric current and the non-conductors. They are called semiconductors. These materials conduct electricity less readily than conductors but much better than insulators.
Semiconductors include almost all minerals, many chemical elements, a great variety of chemical compounds, alloys of metals, and a number of organic compounds. Like metals, they conduct electricity but they do it less effectively. In metals all electrons are free and in insulators they are fixed. In semiconductors electrons are fixed, too, but the connection is so weak that the heat motion of the atoms of a body easily pulls them away and sets them free.
Heat is by no means the only phenomenon influencing semiconductors. They are sensitive to light, too. Just as they are influenced by falling light, semiconductors are also influenced by all radiation. Generally speaking, they are so sensitive that a heated object can be detected by its radiation.
Such dependence of conductivity on heat and light has opened up great possibilities for various uses of semiconductors. The semiconductor devices are applied for transmission of signals, for automatic control of a variety of processes, for switching on engines, for the reproduction of sound, protection of high-voltage transmission lines, speeding up of some chemical reactions, and so on. On the one hand they may be used to transform light and heat energy directly into electric energy without any complex mechanism with moving parts, and on the other hand, they are capable of generating heat or cold from electricity.
Russian engineers and scientists turned their attention to semiconductors many years ago. They saw in them a means of solving an old engineering problem, namely, that of direct conversion of heat into electricity without boilers or machines. Semiconductor thermocouples created in Russia convert heat directly into electricity just as a complex system consisting of a steam boiler, a steam engine and a generator does it.
Answer the questions.
1. What are semiconductors?
2. What do semiconductors include?
3. What are semiconductors influenced by?
4. What are semiconductor devices applied for?
5. Did Russian engineers turn their attention to semiconductors many years ago?
ВАРИАНТ 5
I. Перепишите следующие предложения, подчеркните в каждом из них глагол-сказуемое и определите его видо-временную форму и залог. Переведите предложения на русский язык.
1. Much work had been done for improving soil fertility on this farm.
2. Modern agriculture is developing in close contact with science and new technologies.
3. Our industry will increase the output of faster and more powerful tractors.
4. The driver usually increases speed gradually.
5. Some cities are so noisy and polluted that in many places vehicles have been banned in the city centre.
6. I was watching TV from 7 to 9 p. m. yesterday.
7. Ann had done her homework before her parents came.
II. В следующих предложениях подчеркните Participle I и Participle II установите функции каждого из них, т.е. укажите, является ли оно определением, обстоятельством или частью глагола-сказуемого. Переведите предложения на русский язык.
1. A letter sent from St. Petersburg today will be in Moscow tomorrow.
2. When sending the telegram, she forgot to write her name.
3. A fish taken out of the water cannot live.
4. They will be working at that time tomorrow.
5. He had translated the text before I came.
III. Работа с текстом:
a) переведите текст письменно на русский язык;
b) составьте глоссарий (13-15 слов или словосочетаний терминологического характера с их значениями);
с) письменно ответьте на вопросы.
DYNAMOS
The term «dynamo» is applied to machines which convert either mechanical energy into electrical energy or electrical energy into mechanical energy by utilizing the principle of electromagnetic induction. A dynamo is called a generator when mechanical energy supplied in the form of rotation is converted into electrical energy. When the energy conversion takes place in the reverse order the dynamo is called a motor. Thus a dynamo is a reversible machine capable of operation as a generator or motor as desired.
A generator does not create electricity, but generates or produces an induced electromotive force, which causes a current to flow through a properly insulated system of electrical conductors external to it. The amount of electricity obtainable from such a generator is dependent upon the mechanical energy supplied. In the circuit external to a generator the e. m. f. causes the electricity to flow from a higher or positive potential to a lower or negative potential. In the internal circuit of a generator the e. m. f. causes the current to flow from a lower potential to a higher potential. The action of a generator is based upon the principles of electromagnetic induction.
The dynamo consists essentially of two parts: a magnetic field, produced by electromagnets, and a number of loops or coils of wire wound upon an iron core, forming the armature. These parts are arranged so that the number of the magnetic lines of force of the field threading through the armature, coils will be constantly varied, thereby producing a steady e. m. f. in the generator or a constant torque in the motor.
Answer the questions.
1. What is the term “dynamo” applied to?
2. What kind of a generator is called dynamo?
3.Isa dynamo a reversible machine capable of operation as a generator or motor as desired?
4. How many parts does dynamo consists of?
5. How are these parts arranged?
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