Translate into Russian and put down the Russian equivalents. Then translate the Russian equivalents back into English (orally).

a. current capacity	______________________________
resistor temperature	______________________________
voltage output	______________________________
current value	______________________________
b.to start supplying energy	______________________________
to stop operating	______________________________
to start lightening	______________________________
to stop lightening the bulbs	______________________________
c. to operate well	______________________________
to operate badly	______________________________
to increase the voltage output	______________________________
to substitute the resistor	______________________________

        

4. Read and translate into Russian. Mind one:

1. The element has a trouble. It operates badly. It should be substituted by a new one.

2. The element with a trouble was substituted with a new one and the cell started operating.

 

Electric Cells

An electric cell is used to produce and supply electric energy. It consists of an electrolyte and two electrodes. Electrodes are used as terminals, they connect the cell to the circuit - current passes through the terminals and the bulb lights.

Cells can be connected in series, in parallel and in series-parallel. In order to increase the current capacity cells should be connected in parallel. In order to increase the voltage output cells should be connected in series. In case a battery has a large current capacity and a large voltage output, its cells are connected in series-parallel.

When cells are connected in series the positive terminal of one cell is connected to the negative terminal of the second cell, the positive terminal of the second cell - to the negative terminal of the third... and so on.

When cells are connected in parallel their negative terminals are connected together and their positive terminals are also connected.

Fig. 6    Fig. 7

In case a cell has a trouble it stops operating or operates badly. This cell should be substituted by another one.

 

5. Complete the sentences using the correct variant:

1. A cell is used	a) to increase the voltage output. b) to reduce the current capacity. c) to supply electric energy.
2. The terminals of a cell are used	a) to conduct current. b) to increase voltage. c) to connect the battery to a circuit.
3. When cells are connected in series	a) all the positive terminals are connected together. b) all the negative terminals are connected together. c) the positive terminal of one cell is connected to the negative terminal of the second.
4. Cells are connected in series in order	a) to increase the current capacity. b) to increase the voltage output.
5. In order to increase the current capacity	a) cells are connected in series, b) cells are connected in parallel.

6. Answer the following questions:

1. What is a cell used for?

2. What does a cell consist of?

3. What is the function of the terminals?

4. In what way are cells connected in order to increase the voltage output?

5. In what way are cells connected in order to increase the current capacity?

6. In what way are the terminals of series cells connected?

7. In what case does a cell stop operating?

8. What should be done in case it stops operating?

 

7. Solve these problems:

1. Suppose that you have four electric cells. The current capacity of each cell equals l.5 amp, the voltage output equals 2 V.

a) Connect the cells in series. In what way should it be done?

b) Connect the battery to a circuit whose resistance value equals15 ohms. What is the value of current in the circuit?

2. Suppose that you have three cells of the same value.

a) Connect them in parallel. In what way should it be done?

b) Connect the second battery to the same circuit: what will it result in?

Suppose that one of the cells stops operating. What should be done in this case?

 

 

Unit Ten [10]

1. a) Cover the right column and read the English words. Translate them into Russian and check your translation.

b) Cover the left column and translate theRussian words back into English.

capacitor	[kəˈpæsɪtə]	конденсатор
insulator	[ˈɪnsjuleɪtə]	изолятор
frequency	[ˈfriːkwənsi]	частота
distance	[ˈdɪstəns]	расстояние
advantage	[ədˈvɑːntɪdʒ]	преимущество
disadvantage		недостаток
plate		анод (лампы)
part	[pɑːt]	часть
to apply	[əˈplaɪ]	прилагать, применять
to move	[muːv]	двигать(ся)
to prevent		предотвращать
reason		причина
forthisreason		по этой причине
besides		кроме того
provided that		при условии что