Match each word from the text with its synonym.

1. property a) shape

2. tool b) solidity

3. force c) characteristic

4. application d) power

5. form e) capacity

6. ability f) use

7. hardness g) instrument

 

6. Put these word combinations in the right order to make sentences:

1. All ductile materials / necessarily ductile / are malleable / are not / but all malleable materials /.

2. Hardnessis / and deformation / abrasive wear / to resist / indentation/the ability /.

3. Durabilityis / with time / tear and deterioration / to withstand wear / the ability /.

4. Plastic materials / less prone to / and are therefore durable / are generally / corrosive effects /.

5. Strengthis / of a material to / without breaking or / the ability / withstand force / permanently bending /.

6. Structures such as / tall building / a degree of elasticity / bridges and/must have /.

7. Hardness is / and saws / such as turning tools / the important property of / drills, files / cutting tools /.

 

Group the following words into three columns: nouns, adjectives and verbs. Some of them fit into more than one column.

Mechanical,property, material, react, subject, external, force, stress, load, area, strain, result, application, define, distortion, extension, compression, length, strength,elasticity,bent, flex, return, previous, form, remove, structure, bridge, tall, building, plasticity, ability, change, fracture, become, plastic, heat, extent, shape, call, malleability, ductility, undergo, cold, deformation, ductile, malleable, hardness,resist, abrasive, wear, indentation, important, tool, drill, file, saw, toughness, brittleness,brittle.

 

 

NOUNS	ADJECTIVES	VERBS

 

8. Read the clues and complete the crossword:

^1

^2

^3

^4

^5

^6

^7

^8

^9

^10

^11

 

Across:   The quality of material to be hard but easily broken.   The ability to last; long-lasting.   The quality of being plastic.   The quality of being tough.   The quality of being hard.   The condition of being tightly pulled or stretched.   The outer form of something, by which it can be seen to be different from something else.   The quality or degree of being strong or powerful.

Down:   The quality of material, such as rubber, to spring back into shape after being stretched or bent.   The quality or state of being stable.   The force of weight caused by pressure.

 

LISTENING

9. Listen to the text and answer the questions:

1. Where does the conversation take place?

2. What tool is being discussed?

3. Which materials can be used for its different parts?

4. What material is mentioned as expensive?

5. What material is mentioned as one of the hardest?

6. What requirements to the material do the engineers need?

7. Why it is important for the material of a tool to have a good degree of thermal stability?

Listen to the text and complete the sentences.

1. That’s certainly a scary-looking collection of __________.

2. The latest ones can __________ at over half a million revs per minute.

3. The requirement is abrasion __________, of course.

4. Obviously, they need to be very __________.

5. The last thing, you want is __________ material.

6. Drilling into a tooth at __________ speed, you obviously get a lot of heat build-up.

7. You can actually __________ burning.

 

SPEAKING

11. Work in small groups. Imagine that you are a 1^st year student and you have to prepare for an examination in physics. Discuss the differences between the following mechanical properties of materials:

- strength and strain

- strength and resistance

- elasticity and plasticity

- stability and durability

- hardness and toughness.

Work in pairs. Discuss the following quotations with your partner.

1. “After a certain high level of technical skill is achieved, science and art tend to coalesce in esthetics, plasticity, and form. The greatest scientists are always artists as well.”

Albert Einstein

2. “Man is unique not because he does science, and he is unique not because he does art, but because science and art equally are expressions of his marvelous plasticity of mind.”

Jacob Bronowski (Mathematician and science writer)

3. “Every man of action has a strong dose of egoism, pride, hardness, and cunning. But all those things will be regarded as high qualities if he can make them the means to achieve great ends.”

Charles de Gaulle

4. “There is only one quality worse than hardness of heart and that is softness of head.”

Theodore Roosevelt

5. “I try not to break the rules but merely to test their elasticity.”

Bill Veeck (American businessman)

WRITING

13. Imagine you are an architect and you are going to design a building, a bridge, a sky-scraper, etc. What should be done to avoid engineering or design disaster? Write a short paragraph (60-80 words) to express your point of view. You may use words and word combinations in the box:

- design and construction - dimensions of the object

- analysis of the design - moveable structure

- detailed structural analysis - substandard design

- draw a diagram - collapse

- scientific calculations - mechanical properties

GRAMMAR IN USE

These tasks can help you to practise the Past Simple Passive (See Appendix 1 p. 228 – 230) and do the following exercises.

In the following sentences underline the verbs and define the voice (Active / Passive).

1. Strain was defined as the amount of distortion (extension or compression) that takes place per unit of length.

2. Stabilityis the ability to resist changes in shape and size over time.

3. Force caused material to become stressed.

4. Geothermal energy was produced below the earth's surface.

5. The main sources of greenhouse gas emissions include fossil fuel generating by plants and transportation vehicles.

6. Manufacturers chose plastic containers for many different reasons.

7. Oil was formed in underground rocks millions of years ago.

 

15. Transform the sentences from the Active into Passive Voice, as in the example.

Example: Romans cremated Julius Caesar’s body 2,000 years ago.

Julius Caesar’s body was cremated 2,000 years ago.

1. Primitive man found metals free in nature.

2. They changed the shape of material by rolling.

3. Someone warped this wooden thing.

4. If someone mixed tin with copper the resulting substance would be harder.

5. The Egyptians and Assyrians made some use of iron a number of centuries before our era.

6. Scientists developed methods for separating iron from its ores in reasonably large quantities and at fairly low cost.

7. They deformed cold plastic by bending.

 

Put the questions into the Passive Voice.

1. When did Pasteur discover Penicillin?

2. Where do people speak Mandarin?

3. Did Spain win the last basketball Olympics?

4. Do people speak English in Hawaii?

5. How many paintings did the police find?

6. When did Cook discover Australia?

7. Did the government order them to build a new bridge?

 

Complete the following report of an accident which happened in a factory. Use the correct form of the verbs in brackets.

On Friday morning at 9.25 a worker in the chemical plant (a) ….. (to find) by female colleague. He (b) ….. (to lie) on the floor. His colleague (c) ….. (to check) that he (d)….. still ….. (to breathe) and then (e) ….. (to call) the emergency services. The injured man (f) ….. (to take) to hospital where he later (g) ….. (to recover). An investigation at the factory (h) ….. (to find) that a bottle containing a dangerous chemical liquid (i) ….. (to leave) open. Vapour from the liquid (j) ….. (to escape) into the air. While he had been working in the room he (k) ….. (to become) unwell. He (l) ….. (to become) drowsy and then (m) ….. (to fall) unconscious. Investigating officers are interviewing everyone who (n) ….. (to work) in the factory that morning.

UNIT 13

NUMBERS

LEAD-IN

How are numbers classified? Give examples of rational and irrational numbers.