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WORD BUILDING. 4. Translate the following words analyzing their word-formation model:
4. Translate the following words analyzing their word-formation model:
Completely, impossible, mysterious, different, communication, conductor, magnetism, magnetic, generator, arrangement, endlessly, remarkably, fundamental, longer, harder
5. Guess the meaning of the words in bold type:
Progress– progressive, direction – directionless,simple – simplicity,importance– important,technology– technological – technologically,to construct– construction — to deconstruct – deconstructive,to limit – to delimit,certain – uncertainty,security – insecurity
6. Translate the following complex words:
Fireplace; postcard; meanwhile; well-established; post-graduate; undergraduate; multi-coloured; straightforward, full-time; waterpower; hydroelectric; high-pressure; fan-like; electromagnetic; electromagnet; windmill; sunlight; semiconductor; doorbell; single-phase
7. Read and memorize the following words and word combinations:
8. Read the text below to learn about electricity, conductors and electrical circuits:
Text 10 A
What is Electricity?
Electricity completely surrounds us. For most of us modern life would be impossible without it. Here are just a few examples:
§ Throughout your house, you probably find electric outlets where you can plug in all sorts of electrical appliances.
§ Most portable devices contain batteries, which produce varying amounts of electricity depending on their size.
§ During a thunderstorm, there are huge bolts of electricity called lightning that shoot down from the sky.
§ On a much smaller scale, you can get a shock from static electricity on dry winter days.
§ It is easy to create electricity from sunlight using a solar cell; or you can create electricity from the chemical energy in hydrogen and oxygen using a fuel cell.
So what is this mysterious stuff that we call electricity? Where does it come from, and why is it able to do so many different things? The electricity that we get from power outlets and batteries can power all different kinds of devices. The fact is that electricity can be used in a thousand different ways. For example:
§ Electric motors turn electricity into motion.
§ Light bulbs, fluorescent lamps and LEDs* turn electricity into light.
§ Computers turn electricity into information.
§ Telephones turn electricity into communication.
§ TVs turn electricity into moving pictures.
§ Speakers turn electricity into sound waves.
§ Stun guns turn electricity into pain.
§ Toasters, hair dryers and space heaters turn electricity into heat.
§ Radios turn electricity into electromagnetic waves that can travel millions of miles.
§ X-rays machines turn electricity into X-rays.
It is hard to imagine modern people living without electricity. In electricity’s absence, we end up reverting back to fireplaces for heat, wood-fired stoves for cooking, candles for light and the slide rules for computation. To talk over long distances we are left with smoke signals and postcards. Electricity starts with electrons. You know that every atom contains one or more electrons; you also know that electrons have a negative charge. The electrons are tightly bound to the atoms. Wood, glass, plastic, ceramic, air, cotton ... These are all examples of materials in which electrons stick with their atoms.
Because the electrons don’t move, these materials cannot conduct electricity very well, if at all. These materials are electrical insulators. But most metals have electrons that can detach from their atoms and move around. These are called free electrons. Gold, silver, copper, aluminum, iron, etc., all have free electrons. The loose electrons make it easy for electricity to flow through these materials, so they are known as electrical conductors. They conduct electricity.
The moving electrons transmit electrical energy from one point to another. Electricity needs a conductor in order to move. There also has to be something to make the electricity flow from one point to another through the conductor. One way to get electricity flowing is to use a generator. A generator uses a magnet to get electrons moving.
There is a definite link between electricity and magnetism. If you allow electrons to move through a wire, they will create a magnetic field around the wire. Similarly, if you move a magnet near a wire, the magnetic field will cause electrons in the wire to move. A generator is a simple device that moves a magnet near a wire to create a steady flow of electrons.
One simple way to think about a generator is to imagine it acting like a pump pushing water along. Instead of pushing water, however, a generator uses a magnet to push electrons along. This is a slight over-simplification, but it is nonetheless a very useful analogy.
There are two things that a water pump can do with water:
§ A water pump moves a certain number of water molecules.
§ A water pump applies a certain amount of pressure to the water molecules.
In the same way, the magnet in a generator can:
§ push a certain number of electrons along
§ apply a certain amount of «pressure» to the electrons
In an electrical circuit, the number of electrons that are moving is called the amperage or the current, and it is measured in amps. The «pressure» pushing the electrons along is called the voltage and is measured in volts. So you might hear someone say, «If you spin this generator at 1,000 rpm, it can produce 1 amp at 6 volts».
One amp is the number of electrons moving (1 amp physically means that 6.24 x 1018 electrons move through a wire every second), and the voltage is the amount of pressure behind those electrons. Whether you are using a battery, a fuel cell or a solar cell to produce electricity, there are three things that are always the same:
§ The source of electricity will have two terminals: a positive terminal and a negative terminal.
§ The source of electricity (whether it is a generator, battery, etc.) will want to push electrons out of its negative terminal at a certain voltage.
§ The electrons will need to flow from the negative terminal to the positive terminal through a copper wire or some other conductor. When there is a path that goes from the negative to the positive terminal, you have a circuit, and electrons can flow through the wire.
§ Electrical circuits can get quite complex. But at the simplest level, you always have the source of electricity (a battery, etc.), a load (a light bulb, motor, etc.), and two wires to carry electricity between the battery and the load. Electrons move from the source, through the load and back to the source.
Moving electrons have energy. As the electrons move from one point to another, they can do work. In an incandescent light, for example, the energy of the electrons is used to create heat, and the heat in turn creates light. In an electric motor, the energy in the electrons creates a magnetic field, and this field can interact with other magnets (through magnetic attraction and repulsion) to create motion. Each electrical appliance harnesses the energy of electrons in some way to create a useful side effect.
Notes on the text
*LED - light-emitting diode - светодиод, светоизлучающий диод, СИД
TEXT AND VOCABULARY EXERCISES
9. Find in the text the words or phrases which mean the same as:
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