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Translate the following sentences into English



1. Розкажіть нам все про ваш винахід.

2. Ніхто не знав нічого про Америку до того як Колумб відкрив її.

3. Хтось вчора залишив журнал у нашій аудиторії.

4. Чи є тут хтось хто знає англійську мову?

5. Деякі винаходи покращили життя людей.

6. Вони нічого не сказали.

7. Чи є в будинку хто-небудь? – Так, там є хтось.


UNIT 18

TYPES OF ENGINES

LEAD-IN

 

1. What types of engines are used to drive these means of transport?

A B C D

 

2. What other types of engines do you know? What is the difference between them?

READING

Read the text and decide whether the statements that follow are true or false.

Types of Engines

An engine or motor is a machine designed to convert energy into useful mechanical motion.

Devices converting heat energy into motion are referred to as engines, which come in many types. A common type is a heat engine such as an internal combustion engine which typically burns a fuel with air and uses the hot gases for generating power. External combustion engines such as steam engines use heat to generate motion via a separate working fluid.

A common type of motor is the electric motor. This takes electrical energy and generates mechanical motion via varying electromagnetic fields.

Other motors include pneumatic motors that are driven by compressed air. Motors can also be driven by elastic energy, such as springs. Some motors are driven by non combustive chemical reactions. Molecular motors like myosins in muscles generate useful mechanical motion in biological systems by chemical reactions.

Originally an engine was a mechanical device that converted force into motion. Military devices such as catapults, trebuchets and battering rams are referred to as siege engines. Most devices used in the industrial revolution were referred to as engines, and this is where the steam engine gained its name.

In modern usage, the term is used to describe devices capable of performing mechanical work, as in the original steam engine. In most cases the work is produced by exerting a torque or linear force, which is used to operate other machinery which can generate electricity, pump water, or compress gas. In the context of propulsion systems, an air-breathing engine is one that uses atmospheric air to oxidise the fuel carried rather than supplying an independent oxidizer, as in a rocket.

In common usage, an engine burns or otherwise consumes fuel, and is differentiated from an electric machine (i.e., electric motor) that derives power without changing the composition of matter. A heat engine may also serve as a prime mover, a component that transforms the flow or changes in pressure of a fluid into mechanical energy. An automobile powered by an internal combustion engine may make use of various motors and pumps, but ultimately all such devices derive their power from the engine.



The term motor was originally used to distinguish the new internal combustion engine-powered vehicles from earlier vehicles powered by steam engines, such as the steam roller and motor roller, but may be used to refer to any engine.

 

 

1. Civil devices such as catapults, trebuchets and battering rams are referred to as siege engines.

2. External combustion engines such as steam engines use heat to generate movement via a separate working fluid.

3. Most devices used in the industrial revolution were referred to as motors, and this is where the steam engine gained its name.

4. An engine or motor is a machine designed to convert energy into important mechanical motion.

5. Electric motor takes electrical power and generates mechanical motion via varying electromagnetic fields.

6. Originally an engine was a mechanical machine that converted force into motion.

7. Molecular motors like myosins in muscles generate useful automatic motion in biological systems by chemical reactions.

 

T T T T T T T
F F F F F F F

 





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