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UNIT 1

I. Выпишите из Прил. 1 значения следующих слов, запомните их:

movement (n), according to (prep), permit (v),flow (v, n).substance(n), therefore (adv),provide (v),path (n),copper (n),liquid (a, n),release (v),perfect (a) .allow (v), behave (v),act (v),germanium (n) silicon (n).condition (n),mixture (n), device (n).

II. Выпишите из Прил. 2 значения следующих терминов, запомните их:

III. Прочтите следующие интернациональные слова и дайте их русский

эквивалент:

battery (n), electron (n), material (n), classify (v), group (n), electric (a), category (n), metal,(n), cable (n), ignore (v), temperature (n), positive (a).

IV. Прочтите следующие слова, определите по суффиксу, какой частью речи они являются, переведите их:

V. Прочтите и переведите следующие пары слов, образованных по способу конверсии V « N, V« A:

flow (n) – flow (v), contact (n) – contact (v), charge (n) – charge (v), liquid (n) – liquid (a).

VI. Дайте исходную форму следующих слов:

classified, readily, used, easily, switches, permitting..

VII. Прочтите и переведите следующие микротексты, обращая внимание на указательные местоимения this – “эта”, “это”, “этот”; these – “эти”.

  1. Hans Oërsted discovered that an electric current flowing through a conductor creates (создавать) a magnetic field around it. This discovery was later used to make an electromagnet. 2. In 1833 Faraday discovered the effects of passing (пропускание) an electric current through certain solutions (растворы), He called these effects the laws (законы) of electrolysis, 3. The passage of current may produce light. This can happen (случаться) in a number of ways.

VIII. Прочтите и переведите сдедующие предложения, учитывая, что местоимения this, these в функции заместителей ранее упомянутых существительных переводятся местоимениями “он”, “она”, “оно”.

1. A simple capacitor (конденсатор) is made from two metal plates, called electrodes. These are separated by an insulating material such as air, paper, or mica (слюда). 2. All insulators will allow some flow of electrons, however this can be usually ignored. 3. The main contacts of a switch are called poles. These are connected when the switch is on.

IX. Прочтите и переведите следующие предложения, учитывая различные значения as: a) союз: “когда”, “так как”, “поскольку”, “ибо”, б) наречие: “как”; as...as – так...как.

1. Resistance represents (представлять) the energy dissipated (рассеивать) by electrons as they move through the atomic structure of a conductor. 2, An electric current can be described as electric charge in motion. 3. As electrons are negatively charged they are attracted by a positive charge and repelled (отталкивать) by a negative charge. 4. Semiconductors can conduct electricity better than insulators but not as readily as metals.

X. Прочтите следующий текст, скажите, о чем в нем идет речь.

CONDUCTORS, INSULATORS AND SEMICONDUCTORS

1. If we connect a battery across a body, there is a movement of free electrons towards the positive end. This movement of е1eсtrons is an electric current. All materials can be classified into three groups according to how readily they permit an electric current to flow. These are: conductors, insulators and semiconductors,

2. In the first category are substances, which provide an easy path for an electric current. All metals are conductors, however some metals do not conduct well. Manganin (манганин), for example, is a poor conductor. Copper is a good conductor, therefore it is widely used for cables. A non-metal, which conducts well, is carbon. Salt water is an example of a liquid conductor.

3. A material, which does not easily release electrons, is called an insulator. Rubber, nylon, porcelain (фарфор) and air are all insulators. There are no perfect insulators. All insulators will allow some flow of electrons, however this can usually be ignored.

4. Semiconductors are midway (промежуточное положение) between conductors and insulators. Under certain conditions they allow a current to flow easily but under others they behave as insulators. Germanium and silicon are semiconductors Mixtures of certain metallic oxides also act as semiconductors. These are known as thermistors. The resistance of thermistors falls rapidly as their temperature rises. They are therefore used in temperature sensing devices.

Прочтите 2 и 3 абзацы текста, найдите ответ на следующие вопросы:

What materials are called conductors? Do all metals conduct well? What metal is a poor conductor? Why is copper widely used for cables? What substance is an example of а liquid conductor? What materials are called insulators? What insulators are mentioned in the text? Do insulators allow any flow of electrons?

XI. Замените подчеркнутые слова синонимами из текста.

1. The flow of free electrons is an electric current. 2. Materials in the first group are called conductors. 3. Materials, which provide a path for an electric current, are conductors. 4. All insulators permit some flow of electrons, 5. Germanium sometimes acts as an insulator and sometimes as a conductor.

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