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These students will be sent to Moscow to take part in the conference.
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II. Перепишите и письменно переведите предложения, обращая внимание на разные значения слов it, that, one.
The crowd came close to the speaker, as it was interested in the theme of his
Speech.
One must choose a profession which one likes.
My room is very light, that of my brother is not so light but it is large.
III. Перепишите и письменно переведите предложения, обращая внимание на разные значения глаголов to be, to have, to do.
The examination paper had to contain not less than ten grammar exercises.
This book does not give any information on the history of chemistry.
I have been to Kiev this summer.
All the students were present at the lecture yesterday.
A new pump station is to be set up in this cotton-growing area.
IV. Перепишите и письменно переведите предложения, обращая внимание на функцию причастия, герундия, инфинитива.
He was informed about their coming to Moscow.
Energy is defined as the ability to do work.
While building the bridge the workers used new materials.
To study geometry means to train logical thinking.
V. Прочтите и устно переведите текст. Перепишите и письменно переведите 1, 2, 3 и 4-й абзацы.
ATOM AND ELECTRON
Present atomic theories, based on the atom model, place the mass and the positive charge of an atom in a central nucleus, surrounded by moving electrons. The nucleus is composed of neutrons and protons. Neutrons have a mass approximately one-sixteenth that of the mass of the oxygen atom and have zero electrical charge. The proton has a mass slightly lighter than that of the neutron and approximately equal to the mass of the hydrogen H.
The chemical elements are differentiated by varying numbers of protons and neutrons in the nucleus, numbers of protons being equal to the atomic number, hydrogen having one, helium two, and so on.
The electron is the smallest known indivisible unit of electric charge. Early experimenters succeeded in the measuring the ratio of the charge of the electron to mass, and in 1910 the charge was first measured, thus determining these properties of the electron.
The electron appears to have a dual personality, at times being best thought of as a particle, and in other experiments seeming to require wave properties for a satisfactory explanation of the phenomena.
Electric current is due to the movement of electric charges, frequently referred to as electrons. However, long before the existence of the electron was known, it was customary to speak of electric current as due to movement of positive charges from positive to negative in a metallic circuit external to the source.
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КОНТРОЛЬНОЕ ЗАДАНИЕ №3.
ВАРИАНТ 3.
I. Перепишите и письменно переведите предложения. Определите видовременную форму и залог сказуемого.
The construction of the oil center began after the plan had been adopted.
These text-books in chemistry were printed in our print shop.
A chain of thermal and atomic plants was built in 1970s in our country.
II. Перепишите и письменно переведите предложения, обращая внимание на разные значения слов it, that, one.
A barometer is an instrument that measures air pressure.
As the experiment was very interesting many people watched it.
One can easily forget foreign words that one does not use every day.
III. Перепишите и письменно переведите предложения, обращая внимание на разные значения глаголов to be, to have, to do.
Every candidate to the Institute has to take exams.
We did not know any student in that group.
He was the best football player of our school.
This new school building was to be ready last month.
Usually we have two lectures every day.
IV. Перепишите и письменно переведите предложения, обращая внимание на функцию причастия, герундия, инфинитива.
The teacher told the pupils to learn the poem by heart.
Seeing is believing.
The melting snow flows down from the roofs through pipes.
The transmitter operating on the low frequencies was constructed by these
Students.
V. Прочтите и устно переведите текст. Перепишите и письменно переведите 1, 2, 3 и 4-й абзацы.
ELECTROMAGNETIC WAVES
The conversion of sound waves into electric currents and the amplification of these currents are two basic electronic techniques required for record players, different electronic techniques.
There are many reasons why it is not possible to transmit radio waves of very low frequencies, but for one things (но, во-первых) the transmitting aerial will be impossibly large. It is therefore not possible to broadcast electromagnetic waves of audio frequencies, and for long-distance transmission it is necessary to resort to higher frequencies and therefore shorter wavelengths.
In general, electromagnetic waves are propagated through the Earth’s atmosphere in two ways: travel over the surface of the Earth, and waves, which leave the surface of the Earth.
Long waves are transmitted over ground and therefore lose a good deal of their energy in passing through ground obstacles; they consequently have only a limited range. The shorter waves escape more easily from the surface of the Earth. Very short waves pass through the ionosphere so they can be used for long-distance communication. This is why the range of TV stations is limited.
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This problem has been overcome in recent years by the use of communication satellite. If the satellite simply reflects the radiation, it is called a passive satellite, where if it receives the signal and retransmits an amplified signal, it is called an active satellite.
КОНТРОЛЬНОЕ ЗАДАНИЕ №3.
ВАРИАНТ 4.
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