I. Translate the following sentences. Pay attention to the use of participles:

1. A direct current is one which always flows through a conducting circuit in the same direction.

2. The tube containing 5 electrodes - the cathode, the plate, the control grid, the screen grid and the supressor grid is called a pentode.

3. When speaking about thermionic emission we should know that all metals are composed of positive and negative charges.

4. This effect prevents the escape of the free electrons to the surrounding space.

5. In electric tubes the emitting material is heated by an electric current flowing through the material or through an electric heater.

6. A control element being placed between the cathode and anode in the tube is called a grid.

7. Having discovered the properties of the electron, scientists used it for the service of man.

8. While isolating and separating radium, Curie found other radioactive elements.

II. Translate the sentences. Pay attention to the use of Participle II as an attribute:

1. A computer processes the information supplied.

2. The resistance of a conductor is proportional to its length, it is inversely proportional to its cross-sectional area and it depends on the material used.

3. The temperature at the sensing head selected is shown on the meter scale.

4. All the information on the word chosen is taken from the vocabulary to the high speed store of the computer.

5. The Russian text translated is printed out on a paper tape.

6. These self-learning cybernetic systems can collect various data needed, analyse them and perform certain operations as a result of the analysis.

7. The machine processes this information given in accordance with the rules of arithmetic or other formal logic and represents the final result in numerical form.

8. At the end of the timed period, the spring must be rewound or the timer reset for the next interval which may range, depending on the type of timer employed. III. Translate the sentences paying attention to the participles as attributes:

1. With increased knowledge of these fluctuations we may improve the accuracy of this test.

2. The measured changes of neutron intensity with magnetiza­tion of the iron proved that the neutron is influenced strongly by the magnetic fields of the iron atoms.

3. The reduction in propellant weight made possible by the use of nuclear rockets permits an increased payload.

4. The intensity recorded during the first few days after the solar protons had arrived showed the decreased intensity of galac­tic cosmic radiation.

IV. State the function of ed-forms and translate the sentences:

1. The tube elements are sealed in an evacuated glass or metal enclosure so that the electrons should have an unobstructed part between the cathode and the anode.

2. In some electronic tubes, when desired, a small amount of inert gas at a low pressure may be added.

3. When made in the form of a filament, it is called the directly heated cathode.

4. The effect of the grid is to increase the flow of electrons from the cathode to anode when charged positively with respect to the cathode.

5. We may effectively control the anode currentproduced by means of the grid.

6. The vocabulary used included 952 English words.

V. Translate the sentences paying attention to the participles as adverbial modifiers:

1. Subsequent observations showed a high degree of variabi­lity, indicating that the X-ray emission changes considerably throughout the sunspot cycle.

2. The nature of the solar particle radiations needs to be explo­red out to distances of many Earth radii, calling for the use of satellites in eccentric orbits.

3. Ordinary hydrogen has a single proton in its nucleus but its heavy isotope has both a proton and a neutron, making its mass number 2 instead of 1.

4. While working to isolate Polonium, the Curies discovered a second radioactive element, calling it "radium."

5. Certain natural radioactive elements which differ greatly from one another in their radioactive properties were found to be chemically inseparable, suggesting that their external structures are identical though their nuclei differ.

6. The penetration of neutrons through the iron was found to be markedly different, depending whether the iron was magnetized or not.

7. A separate compressor must be inserted in the nuclear reactor in order to circulate the coolant gas, resulting in additional mechanical complexity and further loss of thermal efficiency.

VI. Define the function of Participle I in the following sentences and translate them:

1. The scientist working at this design is well known.

2. Carrying out the experiment he made use of some new instruments.

3. These new devices are replacing their older equivalents.

4. Speaking about the new method of work the engineer told us many interesting details.

5. Radio occupies one of the leading places among the greatest achieve­ments of modern engineering.

6. Being cooled water turns into ice.

7. The electric current passing through a wire will heat it.

8. Transistors contain no moving parts.

9. The scientist is carrying on an important research.

10. Developing the new method they achieved good results.

VII. Choose the sentences with Participle I from the ones given below, translate them:

1. The falling water has kinetic energy.

2. While testing the motor we put down the results.

3. There is no simple explanation of the func­tioning of transistors.

4. Obtaining new data engineers can improve their knowledge.

5. Look at the reading of the device.

6. Robots are helping research scientists to answer many difficult questions.

7. By the beginn­ing of the 20th century man had learned something of the structure of the atom.

8. When applying these automatic devices we shall be able to control automatic lines.

9. A person beginning some experiment should be very careful and attentive.

VIII. Find Participle II in the following sentences and translate them:

1 The performance of this type of propulsion system obtained in the initial investigations showed some advantages as compared with electric rockets.

2. Detailed analysis of data obtained in these ways showed that it is this current which produces the very marked variations over the geomagnetic equator.

3. The standard operating conditions employed included a 50V potential difference between the anode and cathode in the ion chamber.

4. The results obtained established beyond doubt that the high concentrations of particle radiation exist in these regions.

5. The results obtained showed no evidence of a marked in­crease of intensity of solar radiation.

IX. Translate the following sentences paying attention to the functions of Participle II:

1. The discovery mentioned remained unknown to most scientists for a long time.

2. The equipment tested required further improvement.

3. When passed through a motor, electric current can do work.

4. The students have conducted all the experiments.

5. These instruments recorded the cosmic rays and the information obtained was sent back by the radar to the ground.

6. When heated, a magnet loses some of its magnetism.

7. The results received changed with the material used.

8. Unless repaired, this part cannot be used in the radio set.

9. The substances investigated showed quite interesting properties.

10. When developed, the device was used for amplification of radio signals.

11. The developed technology enables us to improve the quality of articles produced.

12. The first laser was developed in 1960.

13. The methods introduced received general recognition.

14. The device used in our work is up-to-date.

15. The apparatus tested is looked upon as an experimental one.

16. When required, these data will be appli­ed in our practical work.

17. The investigation analyzed resulted in an interesting discovery.

X. State the functions of Participle I and Participle II:

1. Experiments made with radio waves have shown that the atmosphere conducting layer lies at heights above about 85 km.

2. The principle described above forms the basis of the hydrau­lic press in which pressure created within a liquid by a comparati­vely small force acting on a small piston exerts a much stronger force on another piston of considerably larger diameter.

3. Because all bodies have a constant downward acceleration produced by the pull of gravity, the equations of uniformly acce­lerated motion can be applied to any falling bodies.

5. Such water is about 11 % denser than that formed from ordi­nary hydrogen atoms and oxygen atoms and so is called "heavy water."

6. One can carry out studies of solids with neutrons analogous to those done with X-rays.

7. Rutherford's discovery of nuclear atom, further developed by Bohr, furnished a detailed explanation of the spectrum of the hydrogen atom.

8. The term “cyclotrons” covers cyclotrons of an entirely dif­ferent type from those already described.

9. A force may be defined as the action of one body on another body which changes or tends to change the motion of the body acted on.

10. A detailed discussion of the exact nature of all the funda­mental particles dealt with in physics is unnecessary in this book.

11. In this chapter we shall give some examples of calculations of various types frequently met with in radar.

12. Electrons play an important part in the operation of thermionic valves, including the magnetron and the klystron.

13. This property of the eye, known as "persistence of vision", is utilized in the cinema and in television.

14. The picture we see on the screen really consists of a single spot of light traveling at great speed.

15. Two reflected rays are needed to locate any image formed by a mirror.

16. Some of the video waveforms met with in radar are very different from sine waves, but it is still possible to deal with these waveforms in certain cases on the sine wave basis, by the use of Fourier's theory.

17. We shall not describe the laws of motion in detail here but they enable us to calculate the subsequent movements of objects acted upon by any set of forces.

XI. Translate the sentences with participles, state their functions:

1. Vectors are essentially geometrical quantities, being defined by a magnitude and a direction.

2. If the type of a particle being detected can be identified, then its energy can be calculated.

3. Being bombarded with slow neutrons, uranium splits approximately into halves producing radioisotopes.

4. A little more complicated example is shown in the picture, which shows a box being pulled by a man.

5. Having studied the electronic structure of electricity, we shall now discuss the quantum structure of light on the basis of the photoelectric effect.

6. The light from the object being photographed causes a permanent change in the chemical emulsion.

7. Being heated magnetized steel loses its magnetism.

8. Having defined the units for length, mass, and time, we can express through them the units for all other physical quantities.

9. The color of the light being seen is determined by the fre­quency of the light waves which affect the human eye.

10. All methods being considered at present use electromagnetic fields to hold the particles.

11. Having studied nuclear reactions we now turn to the ques­tion of how these radiations interact as they go through matter.

12. This book is concerned with the design of a specific kind of analog computer in which electrical voltages represent the vari­ables of the physical system being studied.

13. Having listed at the conclusion of the chapter a number of major programmes we now discuss what progress has been made in the systematic study of neutral atmospheric structure.

XII. Translate the following sentences. Pay attention to the use of various participle clauses:

1. Having reduced the high transmission voltage to safe and usable values transformers made possible the economical transmission of electrical energy over long distances.

2. When considering the choice of electrical equipment great care should be taken to specify ratings well suited to the application.

3. An electric controller is a device or group of devices, which serve to govern the electric power delivered to the apparatus.

4. The term "govern" appearing in the definition means the ability to vary, change, or modulate.

5. The substance being heated, the agitation of the free electrons in it is increased.

6. As stated before, the greater the binding energy, the more stable the nucleus.

XIII. Translate the following sentences paying attention to the Absolute Participial Clause:

1. The experiments being demonstrated, all the students watched them with great attention.

2. There are two diagrams in this figure, one of them showing the relation between volume and temperature.

3. A new radio set having been shown to them, they began to examine its details.

4. Electrons leaving the surface, the metal becomes posi­tively charged.

5. We defined the volume, all the measurements having been done with respect to the instruction.

6. The computer performing addition, two numbers to be added come from the memory.

7. Atoms consist of three kinds of particles — electrons, protons and neutrons, the number of particles determining the kind of element.

8. The workers increased the output of measuring instruments, new devices having been applied in all the shops of the plant.

9. The experiment having been carried out, the students left the lab.

10. I was writing the translation, my friend helping me.

11. Part of the energy being changed into heat, not all the chemical energy of the battery is transformed into electric energy.