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5. The negative terminal of a dry cell is the zinc metal container in which all chemical ingredients are sealed, whereas the positive terminal is a round carbon rod.

a) a switch or bundle of switches used to administer corporal punishment;

Сb) a metal shaft that transmits power in axial reciprocating motion c) a slim cylinder of metal, wood, etc.

6. The positive electrode of a storage cell is known to be set of lead grills. иa) a device on a cooker that radiates heat downwards for grilling meat, fish, etc.

b) a device with parallel bars of thin metal.

7. Separators are used between the positive and negative plates of a lead acid battery to prevent short circuit through physical contact.

a) a person or thing that separates;

b)a device acting as a barrier between.

b)Составьте предложения с каждым выделенным словом, используя «лишние» определения из части а).

9. НайдитебАв следующем тексте глаголы, определите их видовременную форму и переведите предложенияДна русский язык:

Around 1936, archaeologists uncovered in a village near Baghdad a set of terracotta jars which each contained a rolled-up sheet of copper which housed an iron rod. Some scientists believe that this may have been an ancient galvanic cell (roughly 2,000 years old, though its age is still debated), and dubbed them the "Baghdad Batteries".ИIt is believed a common food acid, such as lemon juice or vinegar, served as an electrolyte. Modern replicas have successfully produced currents, lending credence to this hypothesis. It is possible these jars were used for electroplating, to produce mild electric shocks as a source of religious experience, or simply used to store ancient scrolls. The claims are controversial because the claims lack any evidence supporting the exact uses of the artifacts, conflicting physical evidence that does not make the objects conducive for electrical functions, and if they were even electrical in nature. As a result, the nature of these objects is based on speculation, and the function of these artifacts remains in doubt.

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10. Выделите в тексте элементы, которые, на ваш взгляд, несут важную информацию. Обсудите ваш выбор с одногруппниками.

11. оставьте логический план текста и на его основе, а также пользуясь ключевыми элементами из упражнения 7, расскажите об аккумуляторах.

/ устройств / процессов. Расскажите, что вы знаете о них. Опредепо формальным признакам часть речи выделенных в тек-

сте слов.

3. Прочтите и переведите текст.

ELECTRICAL MEASURING INSTRUMENTS

General Electrical Principles. To measure the magnitude of any phenomenon calls for the use of theДeffects produced by it. For the measurement of a mass, for example, we determine its weight; or we might utilize the force required to give it a certain acceleration. Again, for the measurement of temperature we use the expansion of solids, liquids, or gases, the change in electrical resistance of a wire, or the thermoelectromotive force produced at the junction ofИtwo conductors, etc. For the everyday measurement such indicating instruments are most convenient, in which the amount of the quantity to be measured is directly shown by the position of a pointer on a graduated scale or dial.

For the production of such instruments, some effect is employed which enables the phenomenon to be measured to produce a mechanical force tending to move the pointer along its scale; this is resisted by a controlling force which tends to move the index in the opposite direction, towards some zero position. The actual displacement of the index, or deflection, is the resultant of these two forces, and is greater the greater the magnitude of the deflecting force or of the phenomenon to be measured.

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As a matter of fact, one single principle is known to underlie all electromagnetic instruments, viz. that the current-carrying circuit tends to enclose as large a magnetic field as possible. In the moving needle galvanometers, the magnetic needle turns so that more of its lines or force pass

through the coil, while in the moving coil instrument the coil sets itself so Сas to enclose as much of the field of the magnet as possible. In the soft iron instruments, the iron moves so as to increase the magnetic flux produced by the coil, and in the dynamometer the moving coil turns so that its magnetic effect increases that of the fixed coil. Should the conducting circuit be made entirely of flexible material in a uniform field, it would become circular in order to enclose the maximum possible area, while, if the current flowed in a liquid conductor – such, for instance, as mercury – it would actually try to reduce its section so as to shorten the path of the lines of

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6. Найдите синонимические соответствия для следующих слов и словосочетаний (при необходимости воспользуйтесь словарем): to require, magnitude, to determine, certain, to undicate, quanity, entirely, path, force, while, to reduce, for example, to such an extent, i.e., utilize, owing to.

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8. Переведите предложения на русский язык, обращая внимание

2. When current flows in the solenoid, a pivoted softiron disc is attracted

towards the solenoid and the movement causes a pointer to move across a scale.

3. A moving-coil instrument, which measures only d.c., may be used in conjunction with a bridge rectifier circuit.

4. An ammeter, which measures current, has a low resistance (ideally zero) and must be connected in series with the circuit.

5. When an ammeter is required to measure currents of larger magnitude, a proportion of the current is diverted through a low-value resistance connected in parallel with the meter.

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