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Experiments show that all gases expand on heating.

, .

, Present Indefinite Tense (3- ).

Hydrogen finds numerous uses in modern industry.

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Means of regulation may include fuel control.

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already, always, never, just, often, seldom, usually), , be.

We usually denote work by W.

W.

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We form any colour, shade and tint by changing the proportions of the primary colours.

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Unit 4

TRANSMISSION MEDIA

Wires and Cables were the original medium for telecommunications and are still the primary means for telephone connections. Wireline transmission evolved from telegraph to telephone service and continues to provide the majority of telecommunications services. Wires connect telephones together within a home or business and also connect these telephones to the nearest telephone switching facility.

Other wireline services employ coaxial cable, which is used by cable television to provide hundreds of video channels to subscribers. Much of the content transmitted by the coaxial cable of cable television systems is sent by satellite to a central location known as the headend. Coaxial cables flow from the headend throughout a community and onward to individual residences and, finally, to individual television sets. Because signals weaken as distance from the headend increases, the coaxial cable network includes amplifiers that process and retransmit the television signals.

Fiber-Optic Cables use specially treated glass that can transmit signals in the form of pulsed beams of laser light. Fiber-optic cables carry many times more information than copper wires can, and they can transmit several television channels or thousands of telephone conversations at the same time. Fiber-optic technology has replaced copper wires for most transoceanic routes and in areas where large amounts of data are sent. This technology uses laser transmitters to send pulses of light via hair-thin strands of specially prepared glass fibers. New improvements promise cables that can transmit millions of telephone calls over a single fiber. Already fiber optic cables provide the high capacity, "backbone" links necessary to carry the enormous and growing volume of telecommunications and Internet traffic.

Radio Waves. Wireless telecommunications use radio waves, sent through space from one antenna to another, as the medium for communication. Radio waves are used for receiving AM and FM radio and for receiving television. Cordless telephones and wireless radio telephone services, such as cellular radio telephones and pagers, also use radio waves. Telephone companies use microwaves to send signals over long distances. Microwaves use higher frequencies than the radio waves used for AM, FM, or cellular telephone transmissions and they can transmit larger amounts of data more efficiently. Microwaves have characteristics similar to those of visible light waves and transmit pencil-thin beams that can be received using dish-shaped antennas. Such narrow beams can be focused to a particular destination and provide reliable transmissions over short distances on Earth. Even higher and narrower beams provide the high-capacity links to and from satellites. The high frequencies easily penetrate the ionosphere (a layer of Earths atmosphere that blocks low-frequency waves) and provide a high-quality signal.

Communications satellites provide a means of transmitting telecommunications all over the globe, without the need for a network of wires and cables. They orbit Earth at a speed that enables them to stay above the same place on Earth at all times. This type of orbit is called geostationary or geosynchronous orbit because the satellites orbital speed operates in synchronicity with Earths rotation. The satellites receive transmissions from Earth and transmit them back to numerous Earth station receivers scattered within the receiving coverage area of the satellite. This relay function makes it possible for satellites to operate as "bent pipes"that is, wireless transfer stations for point-to-point and point-to-multipoint transmissions. Communications satellites are used by telephone and television companies to transmit signals across great distances. Ship, airplane, and land navigators also receive signals from satellites to determine geographic positions.

 

 

GRAMMAR EXERCISES

 

I. Translate the following sentences, pay attention to the Modal Verb with the Infinitive in passive.

1. Electrolysis may be defined as a process, by which a chemical reaction is carried out. 2. The mass may often be defined as the quality of matter remaining constant everywhere. 3. When the forces act in the same direction, the resultant can be found by adding the applied forces. 4. The energy, which has to be supplied by the generator or battery, is transformed into heat within the conductor. 5. The frequency of anoscillator is to be kept constant by means of an oscillating crystal. 6. To detect very weak radio signals a directional antenna and a highly sensitive radio receiver are to be used. 7. A number of scientific problems were to be solved in connection with the construction of a network of electrotransmision lines.

 

II. Translate the following sentences into Russian.

1. Before installing of new equipment the engineers were to test its performance. 2. Due to the application of powerful of relays we shall be able to televise programmes to vast territories. 3. To improve the operation of that system some tubes are to be replaced. 4. According to the design the instrument cabin of a spaceship is to house various transmitters, power sources and other equipment. 5. The pilots had to maintain direct radio contact between the planes.

6. The students were allowed to examine numerous devices installed in the laboratory. 7. The engineers have to investigate the possibilities of improving radio contact in that locality. 8. To provide the required data, a satellite has to be equipped with a transmitter containing a very stable oscillator.

 

III. Translate the following sentences, pay attention to the meanings of the Modal Verbs with the Perfect Infinitive.

1. The experiment must have been done in a wrong way because of the data obtained being in contradiction with Lenz's law. 2. The voltage may have been too high, the insulation being broken down. 3. The friction between the wax and the flannel must have rubbed off some electrons of the flannel molecules and left them on the surface of the wax. 4. The operator should have test the trouble caused due to the conductor being overheated. 5. This magnetized body may have exerted some attractive or repulsive force on the other one. 6. The alpha-grains must have formed during the 30-sec cooling required to reach temperature below which diffusion was negligible. 7. get better results another method ought to h been applied. 8. It must have been known for centuries the colorless glass is cooler at the bottom of a pot than a colorless glass.

 

 

IV. Translate and put the following sentences into the Passive Voice.

Pattern: Other factors may affect the process.

The process may be affect by other factors.

1. This radiation dose may damage the cells. 2. This substance may catalyze for process. 3. The environmental factors may bring about such changes. 4. These conditions may affect the course of the reaction. 5. The structural changes may produce a marked effect. 6. This defect may account for the discrepancy in the results. 7. These organelles may accumulate energy. 8 This mechanism may involve an unknown factor. 9. Ultraviolet radiation may produce ionization.

 

V. Translate the following sentences, pay attention to the different functions since .

1. Since the distance of the electrons from the nucleus is about a hundred thousands times as large as the diameter of the nucleus, most of the atom consists of empty space. 2. Since the end of World War II there has been a rapid development of jet engines. 3. Since the first rocket appeared many changes has taken place in this field of science. 4. Since the jet engine is a powerful source of energy, it is widely used for machines flying at supersonic speed. 5. A few elementary substances such as gold, silver, cuprum have been known since old times. 6. About 100 years passed since the day when radio was discovered.

 

LEXICAL EXERCISES

 

VI. Translate the text without dictionary.

Artificial communication satellites are placed in an orbit around the Earth. They relay radio and television signals around the curved surface of the Earth and thus serve the purpose of intercontinental radio and television transmission. There are two types of satellites in the orbit: active and passive. As for active satellites, they are used to receive, amplify, and retransmit signals being sent for the purpose of communication. The function of passive satellites is only to reflect the transmitted signals from the surface of the Earth.

Artificial satellites are being used to receive and reflect back information about the upper atmosphere and the ionosphere. It is a well-known fact that the ionosphere forms part of the Earths upper atmosphere. It reflects electromagnetic radiations of radio frequencies, which makes it possible to carry out intercontinental radio transmission round the curved surface of the Earth.

 

VII. Translate the following international words.

Radio, genius, human, priority, demonstrate, contribution physical, chemical, university, laboratories, problem, electromagnetic, communication, operation, apparatus, progress, transmission, music, vision, signals, television, meeting, industry, period, centre, radar, telecontrol, telemetric systems, electronic microscopes.

 

VIII. Translate the following word combinations.

1. travelling speed; 2. return pressure; 3. space current; 4. spaceships launched from; 5. altitude flight; 6. travelling wave; 7. long-wave transmitter; 8. velocity microphone.

 

IX. Translate the following word combinations into Russian.

1. The development of science. The development of new methods The development of new devices

2. The performance of a plane The performance of a task

3. The stroke of a piston The stroke of a clock

4. The treatment of a problem The treatment of a metal The treatment of diseases

5. The handling of an instrument The handling of dangerous fission products

 

X. Form the words using the prefixes and translate them into Russian.

re-: to construct, construction, to use, to take, to name, to create, to group, to equip, production

super-: low, critical, to cool, man, to heat, bomb

sub-: to divide, division, station, way, group, normal

en- able, circle, large, close, force, rich

 

GRAMMAR REFERENCES

Infinitive Passive Perfect Infinitive.

Infinitive Passive Perfect Infinitive.

Infinitive Passive , , , . , .

The man was so excited he could not be understood.

, .

must, may might Perfect Infinitive , , , .

The instrument may have been improved because it became more accurate.

, , , .

We now see that this point must have been the center of mass of the body.

, , , .

could Perfect Infinitive .

cannot have made such a serious mistake.

He , .

 

ought (to), should, could might Perfect Infinitive , , , .

You should have changed the current strength at all points of the circuit.

.

You could have done it carefully.

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LEXICAL REFERENCES

(INTERNATIONAL WORDS)

- , , . .

, - : film, text, visit, radio, doctor.

, , : revolution ; atom legal .

, , , . , accumulator, alpha, alphabet, energy, element, economic , , , , .

.

:

atom, proton, focus, cosmos;

plus, integra;

radio, diod, triod.

, physics, mathematics, medicine.

, . :

(, , ) + on

, : electron, photon, neutron, pi mi, ion, microtron.

, : fermion , , . , .

Henry , Joule , Newton , Ohm .

, , . , , . , . . : accurate , ; resin , ; control , . .

,

, .

, , analysis, candidate, scenario, critical, originally, history, pioneer, practical, signal, revolutionary, traditionally . . , . , , , - (, , ). . , activities , ; direction , ; obligation , ; magazine , .

- . , - . , revolutionary changes in tube design- () , ; ssive failures , .

- ptimistic, pessimistic - : optimistic percent ; theory is pessimistic .

- . , , . . , .

 

METHODS OF TRANSLATION





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