Модуль 2 - Времена группы Continuous и Perfect Active Voice (1096806), страница 7
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The scientists received another hologram after they had changed the light spectrum.11. After the researcher had studied the properties of the alloy, he made a report on thе subject.***12. She hadn’t finished her test by 5 o’clock.13. We hadn’t inspected the climate control system by 9 a.m.14. The engineers had not predicted the properties of the substance by the time they got this15.16.17.18.information.They had not begun the experiment before the assistant came.The scientist realized that he had not spotted a distant planet.The observers reported that they had not recorded laser signals from the Universe.We heard that they hadn’t bought up-to-date equipment for the lab.***19. Had the scientists split the nucleus by the middle of the 20th century? – Yes, they had.20.
Had he completed the chemical reaction by the appointed time? – No, he hadn’t.21. Had the engineers written many complicated programmes for the robots before the exhibition22.23.24.25.26.started? – Yes, they had.Had people invented mechanical devices long before the first robot was designed?Had the engineers constructed the first robot systems by the end of the 19th or 20th century? –They had already done it by the end of the 19th century.Why had the engineers equipped this device with new sensors before they put it into operation?What kind of experience had the students got by the end of the term?Who hadn't studied computer engineering before he entered our university? – My brotherhadn't.The Future Perfect Tense (Active):1.2.3.4.5.6.Our colleagues will have introduced their invention into practice by 2014.Our engineers will have reduced power losses in both models by the beginning of the test.We’ll have installed this equipment by the beginning of a new academic year.Our scientific group will have developed a new cooling system by the end of the winter.The water will have frozen by the end of the test.Our assistant will have done all the preparatory work by the time we come to the researchroom.7.
When our counterparts arrive, we’ll have already finished testing a new industrial robot.***8.9.10.11.12.13.They won’t have discussed this interesting problem by tomorrow.The students won’t have finished the experiment by the end of the lecture.We won’t have got any new equipment by next December.By this time next year you won’t have graduated from the institute yet.They won’t have built a new power plant by next year.The students will not have investigated the advantages of machine tools by the end of theirpractice.2814. The engineers will not have constructed a new moving device by the end of May.***15.16.17.18.19.20.21.22.23.24.25.Will she have become a famous scientist by then? – No, she won't.Will the engineers have improved the car design by the opening of the race? – Yes, they will.Will the students have taken their exams by the end of January? - Yes, they will.Will they have finished the first stage of the work by the time the laboratory experiment isover? – No, they won’t.Will the students have performed a series of experiments by the end of this or next week? –They’ll have already done it by the end of this week.What will they have repaired by Wednesday? – They’ll have repaired this control system.How many lectures will we have attended by the end of the course? – You’ll have attended 120lectures.What will have happened to the lead by the end of the experiment? - It will have melted.By what time will the students have learnt everything about electric current?What properties of steel will you have studied by the end of your tests?Who will have connected these pipes by the end of the test? – The instructor will.3.
Тексты для перевода1. CircuitsElectrons with a negative charge, can't "jump" through the air to a positively charged atom. Theyhave to wait until there is a link or bridge between the negative area and the positive area. Weusually call this bridge a "circuit."When a bridge is created, the electrons begin moving quickly. Depending on the resistance of thematerial making up the bridge, they try to get across as fast as they can. If you're not careful, toomany electrons can go across at one time and destroy the "bridge" or the circuit, in the process.In Chapter 3, we learned about electrons and the attraction between positive and negative charges.We also learned that we can create a bridge called a "circuit" between the charges.We can limit the number of electrons crossing over the "circuit," by letting only a certain numberthrough at a time.
And we can make electricity do something for us while they are on their way. Forexample, we can "make" the electrons "heat" a filament in a bulb, causing it to glow and give offlight.When we limit the number of electrons that can cross over our circuit, we say we are giving it"resistance". We "resist" letting all the electrons through.
This works something like a tollbooth on afreeway bridge. Copper wire is just one type of bridge we use in circuits.Before electrons can move far, however, they can collide with one of the atoms along the way. Thisslows them down or even reverses their direction. As a result, they lose energy to the atoms. Thisenergy appears as heat, and the scattering is a resistance to the current.Think of the bridge as a garden hose. The current of electricity is the water flowing in the hose andthe water pressure is the voltage of a circuit.
The diameter of the hose is the determining factor forthe resistance.29Current refers to the movement of charges. In an electrical circuit – electrons move from the negativepole to the positive. If you connected the positive pole of an electrical source to the negative pole,you create a circuit. This charge changes into electrical energy when the poles are connected in acircuit – similar to connecting the two poles on opposite ends of a battery.Along the circuit you can have a light bulb and an on-off switch. The light bulb changes the electricalenergy into light and heat energy.Circuit ExperimentAs a boy, Thomas Edisonbuilt a small laboratory in hiscellar.
His early experiments helped develop a veryinquisitive mind. His whole life was spent thinking about howthings work and dreaming up new inventions. The light bulband movie projector are just two of dozens of inventions.You can build a very basic electrical circuit similar to whatEdison may have crafted as a boy. And you can find out whathappens when a current is "open" compared with when it's"closed."Here's What You need:1.2.3.4.5.6.Penlight bulbFlashlight batteryTwo 6" pieces of insulated wire (any kind will work)Tape to keep the wire on the end of the batteryA small piece of thin flat metal to make a "switch"Small block of woodHere's What to Do1.2.3.4.5.6.To make a switch:Take the block of wood and stick one thumb tack in.Push the other thumbtack through the thin piece of flat metal.Push the thumb tack into the wood so that the piece of metal can touch the other thumbtack (see picture).Connect the first piece of wire to a thumbtack on the switch.Place the light bulb in the center of this wire piece.Tape the end of the first piece of wire to one end of the battery.Tape your second piece of wire to the opposite end of the battery.Attach the end of your second piece of wire to the remaining thumbtack on the switch.You've created an electrical circuit.When you press the switch connecting the two thumbtacks, your circuit is "closed" and your currentflows – turning your light bulb on.
When your switch is up, your circuit is "open" and your currentcan not flow – turning your light bulb off, just like Thomas Edison's may have done.The number of electrons we are willing to let across the circuit at one time is called "current". Wemeasure current using amperes, or "Amps".One AMP is defined as 6,250,000,000,000,000,000 (6.25 x 1018) electrons moving across yourcircuit every second!Since no one wants to remember such a big number, that big number is called a "coulomb," after thescientist Charles A Coulomb who helped discover what a current of electricity is.30The amount of charge between the sides of the circuit is called "voltage." We measure Voltage inVolts.
The word volt is named after another scientist, Alexader Volta, who built the world's firstbattery.You'll remember that back in Chapter 1, we defined energy as the "ability to do work."Well, one volt is defined as the amount of electrical charge needed to make one Coulomb(625,000,000,000,000,000,000 electrons) do one a specific amount of work – which is labeled onejoule.Joule is also named after a scientist, James Prescott Joule. Do you remember him from Chapter 2?Voltage, Current and Resistance are very important to circuits. If either voltage or current is too bigyou could break the circuit.
But if either is too small, the circuit will not be able to work enough to beuseful to us. In the same way, if the resistance is too big none of the electrons would be able to getthough at all, but if it were too small, they would rush though all at once breaking the circuit on theirway.An Electrical Circuit(From humorist Dave Barry's book Dave Barry in Cyberspace)"Electricity is supplied by the wall socket, which is in turn connected to the electrical company viabig overhead wires with squirrels running on them."A question many people ask ... is, 'How come the squirrels don't get electrocuted?' To answer thatquestion, we need to understand exactly what an electrical circuit is."When you turn on a switch, electricity flows through the wire into the appliance, where it isconverted via a process called electrolysis into tiny microwaves. These fly around inside the ovenarea until they locate the Hungry Hombre Heat 'n' Eat Hearty Burrito entree; they then signal thelocation to each other by slapping their tails in a distinctive pattern.
The workers, or drones, then ...swarm around the queen; this causes the rapid warming that makes the entree edible and leads viaamino acids, to digestion."This is followed by grunting and flushing, with the outflow traveling via underground pipes to thesewage treatment plant, which in turn releases purified water into the river, where it is used to formwaterfalls, which rotate the giant turbines that produce the electricity that flows through wires backto your appliance, thereby completing the circuit."So we see that squirrels have nothing whatsoever to do with it.
There is no need for you to worryabout squirrels; believe me, they are not worrying about you."Please Note: THIS IS A JOKE!!!Parallel Circuits!When we have only one circuit that electrons can go through to get to the other side we call it a"series circuit." If we were to set up another circuit next to the first one, we would have two circuitsbetween the charges. We call these "parallel circuits" because they run parallel to each other. Youcan have as many parallel circuits as you want. Parallel circuits share the same voltage, but theyallow more paths for the electricity to go over.
This means that the total number of electrons that canget across (the current) can increase, without breaking either circuit.31Electric MotorsAn electric motor uses circuits wound round and round. These wound circuits are suspendedbetween magnets. (We send a 'thank you' to How Stuff Works Website for their electric motorgraphic.)A motor works through electromagnetism. It has a coiled up wire (the circuit) that sits between thenorth and south poles of a magnet.
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