Tungsten Filament High Resistance

An Amp (A) is a unit measure of the amount of current in a circuit. An ammeter permits the current to be measured.

Molybdenum Wires Low Resistance

Glass Bulb

Very High Resistance

(Insulator)

The pressure that forces the current to flow is measured in Volts (V). A transformer is used to change the voltage of electricity. This allows electricity to be transmitted over long distances at high voltages, but safely used at a lower voltage.

 

A Watt (W) is a unit measure of electric power that depends on amps and volts. The more watts the bulb uses the more light is produced. Watts = Volts x Amps.

a) overhead conductor wires,

b) magnetic field,

c) capacitor,

An Ohm (0) is a unit measure of materials resistance to a flowing current. The filament in this light bulb glows because its high resistance makes it hot. Low resistance of the support wires does not let them glow. The glass has a resistance so high that it does not allow the current to move through it - this property makes glass a good insulator.

 

Provide answers to the questions below.

1. What is electricity and an electron?

2. How is electricity produced?

3. What types of power plants do you know?

4. What is the function of the transformer?

5. How does the light bulb work?

6. Glass is a poor insulator, isn't it?

 

Match the words with the similar meaning.

to convert to solve to absorb to seem to supply usually huge to think

to tackle

large

to turn into

to provide

to consider

to appear

to capture

normally

 

Make up all possible word combinations.

 

Array

huge

electrical

inexhaustible

to power

metal

to supply

 

amount

energy

resource

cars

surface

heat

solar

 

Find in В the derivatives from the words in A.

А В

1. to pollute - power, pollution, production, pressure

2. to charge - change, research, discharge, consumer

3. to power - solar-powered, overcharge, operation, piping

4. to exhaust - explanation, expensive, efficiently, inexhaustible

5. to vary - vice versa, variation, weekly, invention

6. new - well-known, consequently, renewable, efficiency

7. complete - competition, completely, tremendous, economical

 

Engineers make use of machine tools in all their activities. List as many

Applications of machine tools as possible. Compare your list with that of

Your group mates.

 

Paul, a student of Mechanical Engineering, has visited an exhibition

"Advances in Machinery Engineering" and now he is telling his friend

Alex about it. Listen to their dialogue and learn how to name different

Machine tools.

 

Alex: Hello, Paul! Glad to see you. Where have you been? I was looking for you all day yesterday. But unfortunately, I didn't find you.

Paul: You know, our lessons had been finished by five o'clock yesterday and I went to our Exhibition Hall and saw different types of machine tools there, such as lathes, milling machines and grinding machines.

Alex: That sounds interesting. It's impossible to imagine a work shop today that is not equipped with multi-purpose machine tools.

Paul: I can't but agree with you. People have already fully automated all transportation operations.

Alex: And were there any interesting types of machine tools at the Exhibition, I wonder?

Paul: Oh, definitely, the latest developments in the design of machine tools were well represented there. And as far as I know, some of these types will have been put into operation by the end of the next year.

Alex: And what impressed you most of all at the Exhibition?

Paul: Well, you know, there was one fantastic machine known as the "machining centre". This machine performs about a hundred different operations simultaneously.

 

Complete the dialogues.

 

1. А...

В: Well, you see, I had finished the test by 2 o'clock yesterday

and I went to the machine tool works.

A …

 

. A: What types of machine tools did you see at the Exhibition?

B:...

A: Which one did you like most?

B:...

A: Will any of these new machine tools have been put into operation by the end of the year?

B:...