Материал: 2048

Student: Well, the soft iron has high permeability and low retentivity, while steel has low permeability and high retentivity.

Demonstrator: -------------------------------------!!!

11. Прочтите и выучите следующие слова: needle – игла, стрелка (прибора);

cease – прекращать (-ся), переставать, приостанавливать; collapse – руш ться, сплющиваться, обваливаться;

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Рис. 6

2. Прочтите текст и выделите основные темы повествования.

HISTORY OF ELECTRONICSИ

Electronics is the science dealing with devices operated by control of the movement oа electric charges in a vacuum, in gases, or semiconductors: or with the processing of information or the control of energy by such devices. This definition covers the wholу complex family of vacuum and gaseous electron tubes and their applications. It also includes metallic contact or semiconductor rectifiers and the transistors which utilize the control of electrons or positive charges (holes) to process information or to convert energy.

Electrononics was born in the 19-th century. Like hydrolysis or chemistry, it has come into its own only recently. Electronics first established itself, however, in wireless telegraphy. Industrial applications of electronics include control gauging, counting, heating, speed regulation,

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etc. But in a larger field, electronocs leads to automatic control of largescale industrial operations.

Today, electronics has started у new era. Electronic devices are doing simple, but human-like thinking. Some industries are controlled by electronic robots. Automation is the industrial keynote of the day. Planes and rockets are electronically controlled. Some radiotelescopes work like radar to receive radio waves from outer space. Shortly speaking, electronics is not so much a new subject as a new way of looking at electricity.

1. What is electronics? 2. When was electronics born? 3. Where did electronics first establish itself? 4. What does electronics lead to in a larger field? 5. What thinking is electronics doing? 6. In what branches of science and technology is electronics used?

7. Перескажите текст, пользуясь планом и ответами на вопросы.

8. Измените предложения, используя страдательный залог, согласно модели. Обращайте особое внимание на правильное употребление времен.

Model: T.: Electronic devices have revolutionized life.

St.: Life has been revolutionized by electronic devices.

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1. Our engineers have developed many new devices. 2. Mendeleyev observed interesting regularities in the properties of elements. 3. We use boilers for many purposes. 4. We frequently cannot burn fuels completely. 5. The application of electronics is changing the entire life of people. 6. Our engineers will design and construct new thermal power stations.

С9. Измените предложения со страдательным залогом в предложе-

ния с действ тельным залогом, используя образец. Model: T.: Human-like thinking is done by electronics.

иSt.: Electronics does human-like thinking.

1. A new phenomenon of electricity was discovered by Edison. 2. Tremendous hydro potential will be seen by the delegates in Siberia. 3. Computers are usedбАby engineers in all the branches of economy. 4. Considerable scientific and technical progress has been achieved by our people. 5. Large atomic power stations are being constructed by the engineers in our country, US, and UK.

TEXT 2

1. Составьте2 вопроса покартинке (рис.7) и обсудите ихв группе.

Д И

Рис. 7

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2. Просмотрите текст и постарайтесь понять, о чем идет речь.

TRANSISTORS

In 1948 a revolutionary concept was introduced to the electronics world: the invention of the transistor, a crystal which amplified, was an- Сnounced. Nothing like this had happend in electronics since the discovery of the triode vacuum tube in 1907; some years later radio tubes replaced

the crystal detectors of the wireless era.

Now a crystal amplifier, the transistor, challenges the vacuum tube because transistors are smaller, simpler, more efficient, more rugged and longer lived. Already transistors have replaced tubes in hearing aids, with unheard-of battery economy. Moreover, many transistor circuits have fewer components than the vacuum tube circuits, such as multi-vibrators.

4. Задайте общие вопросы к следующим предложениям и дайте краткие ответы.

1. The beginnings of all science lie far back near the dawn of human history. 2. The transformer grew out of the experiment of Faraday. 3. Both elements differ in their chemical and phisical properties. 4. This mixture is

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