Кущ Т.Ю., Воловник М.С. Основы английского языка для судовых электриков (1998)

18. /12 мин./ а) Выпишите из словаря все значения слова.“current”,

б) Прочтите и переведите толкования значения слова “current”.

1. Current means running, flowing, fluent, in circulation or generalise. 2. Current means a running, a flowing, a body of water or air in motion; the flow of the river,'etc.; tendency, drift, transmission of electricity through a conductor.

в) Переведите следующие предложения, в состав которых входит слово “current".

1. We’ll have to introduce a current-controlled relay in this circuit. 2. The resistance to current flow remains constant. 3. Current & future trends may very likely move towards the production of small-scale computers.

г) Переведите следующие словосочетания, в состав которых входит “current”.

a) electric current /с./, b) alternating с. с) c.intensity = c.strength, d) out-of-time-phase с. e) c. affairs f/c. research on semiconductor materials, g) to be in c. use.

19. /4 мин./ а) Прочтите следующие предложения, б) Объяс- ■

ните собеседнику, что такое э.д.с. и разность потенциалов. :

Electromotive force /emf/ is defined as the work per unit charge done by the battery or generator on the.charges in moving them around the circuit. Potential difference between two points is defined as the work per. unit charge done by the charges in moving from one point to the other.

20. / 3 мин./ Найдите в основном тексте 12 интернациональных слов. Прочтите их вслух и переведите.

21. /30 мин./ Прочтите следующий текст. Письменно озаглавьте каждый абзац. Будьте готовы рассказать: а) в каких уело-, виях Ом открыл свой знаменитый закон; б) что такое электрическое сопротивление; в) какое соотношение открыл Ом; г) что помо-' гает определить этот закон; д) при каком условии можно узнать величину тока, используя уравнение, которым выражен закон Ома.

Ohm’s Law

1. G.Ohm was a German physicist. His discovery of the law in 1827 aroused such bitter antagonism that he lost his position. But years later, he was honored by a professorship in physics at the University of Munich. Ohm stated his law having no reliable voltmeters, ammeters or batteries. He employed thermocouple to generate currents.

2. What is ohm? Every electrical conductor opposes the passage of electric charges through it. This opposition arises because of the moving charges colliding with the atomic nuclei & other particles of the conductor. In so doing, the moving charges give up energy, which appears as heat. According to Ohm’s law, electrical resistance is the ratio of the potential difference to the current for a conductor at a given temperature.

3. One ohm is the resistance of a conductor through which the current is 1 ampere when the potential difference across the ends of the conductor is 1 volt. One ohm equals 1 volt per ampere.

4. This is the well known & fundamental law in electricity which makes it possible to determine the current flowing through a

.circuit when the resistance in the circuit & the potential difference applied to it are known. What Ohm discovered was that the ratio of the potential difference between the ends of a.metallic conductor & the current flowing through the metallic conductor is a constant. The proportionality constant is the electj&fcal resistance. Symbolically, Ohm’s law is often written I - V/R

5. If any two of the three quantities : resistance, current & potential difference are known for a circuit, the third can always be determined by substituting in Ohm’s law.

22. /2 мин./ Внимательно слушая или просматривая следующие пары словосочетаний, записывайте номера, в которые включены идентичные пары слов.

1) make up - make up; 2) walk out - watch out; 3) fine loss -fire loss; 4) hold right - hold tight; 5) fast train - fast train; 6) take time - take nine; 7) small house - small hours; 8) fall down,- call down; 9) talk softly - talk softly; 10) to write back - right back; 11) bus stop - bus top; 12) thick fog - thick fog; 13) short visit - short visit; 14) empty pen - empty pan

23. а) Прослушайте описание электрических цепей. Постарайтесь понять и описать электрическую цепь, используя рисунок 3. б) Парная работа. Поговорите со своим партнером о различиях в цепях “а” и “Ь”. Докажите, что в цепи “Ь” не может протекать ток. /Рис.З//8 мин./

К
Fig. 3. Electric circuit.

This is a circuit. Its elements are a voltage source, a resistor & a conductor. A voltage source supplies current. A resistor reduces current. A conductor connects the elements of the circuit. Compare circuit “a” with circuit “b”. What’s the difference'between them? Current passes through circuit “a” while no current passes through circuit “b”. Circuit “b” has an open. No current through circuit “b” results from an open. An open & a short are troubles in a circuit. A trouble in a circuit may result in no current in it.

24. /4 мин./ Слушая условия задачи, запишите числовые данные. Решите обе задачи и назовите результат.

1. A 70-ohm resistance is connected to the circuit. How much is the voltage if the current equals 4 A? 2. How much is the current in the circuit if a 60 V source is connected to a resistance of 1,600 ohms?

25. / 2 мин./ Прослушав/прочитав текст, скажите, как называется закон, о котором идет речь.

This law might have been predicted from the principle of the conservation of energy. When you move a magnet toward a coil & thus induce a current in its windings the induced current heats the wire. In order to supply the energy to do this, you must do work in overcoming an opposing force. If the force did not oppose the motion, you would create energy. Thus the magnetic field of the induced current is seen to oppose the change. This law & the right hand rule can be used to determine the direction of an induced current.

26. /9 мин./ а) Прослушайте/прочтите ряд слов и словосочетаний и запомните их значения.

What’s wrong with your car? - Что случилось с вашей машиной?; to take to pieces - разобрать /машину/; to put it together собрать ее; gear box - коробка передач; to straighten the bumper

- выпрямить бампер; to check the pressure - проверить давление; to put right - правильно установить; windscreen wiper - стеклоочиститель лобового стекла; to give a thorough overhaul - провести тщательный осмотр; except - кроме.