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Date: 2015-10-07; view: 421.

III. Answer the following questions.

I. Copy the underlined words and word-combinations, translate them into Ukrainian and learn them.

II. Find the following words and word-combinations in English in the text: незначні зміни; кількість машин, які використовуються; останній найшвидший тип; електричні двигуни; сила м'язів; найбільше досягнення; мистецтво повідомлення думок; повністю змінили наше життя.

1. What machines of recent origin do you know?

2. What machines of rapid transit do you know?

3. What kind of motors is now used instead of muscle power to operate the machines?

4. What is the role of machines in the home?

5. Have machines completely transformed our life?

Test yourself:

1. A machine is a device that

a) uses force to accomplish something.

b) transmits and changes force or motion into work.

c) all of the mentioned above.

2. A machine receives input from

a) an energy source and transforms it into output in the form of mechanical or electrical energy.

b) an energy source and transforms it into output in the form of mechanical energy.

c) an energy source and transforms it into output in the form of electrical energy.

3. Machines whose input is a natural source of energy are called

a) electric motors.

b) prime movers.

c) generators.

4. Machine elements are

a) basic mechanical parts used as the building blocks of most machines.

b) assembled together to form what we call as complete machine, which performs various applications.

c) individual parts of the machine that move and impact on other parts to make the machine work.

5. General-purpose machine elements can be used

a) in some application.

b) only in specific applications.

c) in any application.

6. Mechanisms are used

a) to transform input forces and movement into a desired set of output forces and movement.

b) to convert between one type of motion and another.

c) all of the mentioned above.