5. Match the words with their definitions;

A conductor of electricity Non-conductors A conductor A circuit

Any substance or material which will afford continuous passage of an electric current when subjected to a difference of electric potential.

Certain substances that are known to possess little conductivity.

A body so constructed of conducting material that it may be used as a carrier of electric current.

A material of relatively high conductivity. A path of an electric current.

A conducting part or a system of parts through which an electric current is intended to flow.

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6. Translate into English:

Рух електричного струму зумовлений рухом електронів. Наявність вільних електронів робить речовину добрим провідником. Ці вільні електрони, що знаходяться в постійному хаотичному русі, під дією е.р.с. рухаються по провіднику у певному напрямку. Якщо електрони рухаються постійно в одному напрямку, струм називається постійним. Якщо ж рух електронів через рівні проміжки часу змінюється на протилежний, струм називається змінним.

Чисті метали вважаються добрими провідниками електричного струму, тому що вони створюють дуже малий опір. Ізоляторами називаються ті речовини, які створюють великий опір електричному струму. Електропровідність також іноді залежить від температури речовини.

6. Tell your group-mates what you know about the capacity of a conductor.

7. Speak on the topic «Capacity».

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Parts 5

Kinds of Circuits

1. Remember the words and word combinations:

Series circuit

Parallel circuit

Network

Path

Device

To be connected in tandem

The positive terminal

The negative terminal

To be fastened

A common point

2. Read and translate the text:

Circuits can be divided into four classes: series, parallel, combination of series-parallel, and network.

Series circuits are those having only one closed path for the flow of electricity. All the elements, or devices which make up the circuit are connected in tandem, one after the other, so that the end of one is connected to the beginning of the other; or, in other words, the positive terminal of one is connected to the negative terminal of the other. If the series circuit is opened anywhere, the current will not flow through the circuit.

A parallel circuit is one divided into two or more branches, each branch carrying part of the current.

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Another way of saying the same thing is that all the elements or devices are connected so that one half of the terminals is fastened to a common point or a common conductor, and the other half is fastened to another common point, or another conductor. •1

3. Answer the questions:

1. What can be divided into four classes?

2. What four classes can circuits be divided into?

3. What are the series circuits?

4. What is the parallel circuit?

4. Explain the meanings of the following words and word combinations. Make up sentences using them.

Series circuit

Parallel circuit

Network

Path

Device

To be connected in tandem

The positive terminal

The negative terminal

To be fastened

A common point

5. Put in the necessary terms:

______ can be divided into four classes: series,

parallel, combination of series-parallel, and network.

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the flow of electricity.

________are those having only one closed path for

________is one divided into two or more branches,

each branch carrying part of the current.

6. Speak on the topic "Kinds of Circuits".

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Part 6

Measuring Devices

1. Remember the words and word combinations:

Ammeter

Voltmeter

Wattmeter

Scale

Ampere

Calibration

Volt

Of the same type or design

Identical moving units

To be used for either meter

Positive or negative lead

In series

Otherwise the readings would be incorrect

Is to be measured

In this instance

As high as possible

Consumed by it

Or else

A drop of potential

Across the circuit

At any instant

By means of

Is the product of

The instantaneous values

Direct reading

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