Read the text and translate it: A Laser



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Read the text and translate it: A Laser



Render the text: Laser

UNIT 2

Pre-text exercises:

Choose the right word: Say, tell, speak, talk

1. Don't … him about our plans. 2. I waited for an answer, but she didn't … a word.

3. He … us that he was going to buy a new car. 4. Do you … English? 5. Mike, we need to … . 6. To … you the truth, I don't remember anything. 7. Did the director … at the conference? 8. Do you know how to … good-bye in Arabic?

2. Find the Ukrainian equivalents for the following English and word combinations:

a) electronic devices, to increase the value, outside your home, current weather conditions, the digital door lock, wireless cameras,

b) за межами вашого дому; безпровідні камери; цифровий дверний замок; електронні прилади; збільшити величину (важливість); поточні погодні умови.

3. Match two parts of word combinations:

1) rainfall …

2) … Door Locks

3) … Camera

4) Roomba … Cleaner

5) little …

6) battery-…

7) a weather …

8) security reasons

a) Wireless

b) guy

c) amounts

d) Vacuum

e) Digital

f) man

g) powered

Read the text, translate and entitle it.

Today's robotic vacuums are a far cry from the first models that you had to track down, stranded somewhere in your house, by their melancholy, "I'm out of power" beeping. The latest products clean your house, remember the layout to increase efficiency, dump their own dirt in a receptacle and find their way back to the charging station so they can rejuice. Roombas run on a rechargeable NiMH battery. The Roomba Red battery pack is rated at 3 amp-hours and takes about seven hours to fully charge to about 18 volts. Some of the more recent Roomba models have cut that charge time down to about three hours. A full charge equals approximately two hours of cleaning time, which in the Roomba world means vacuuming three medium-size rooms before it needs to rejuice. The mobility system consists primarily of two motor-driven, tracked wheels. Roomba steers by alternating the power supplied to each wheel.

The first thing Roomba does when you press "Clean" is to calculate the room size. iRobot is a bit hazy on how it does this, but HowStuffWorks believes that it sends out an infrared signal and checks how long it takes to bounce back to the infrared receiver located on its bumper. Once it establishes the size of the room, it knows how long it should spend cleaning it.

While Roomba is cleaning, it avoids steps (or any other kind of drop-off) using four infrared sensors on the front underside of the unit. These cliff sensors constantly send out infrared signals, and Roomba expects them to immediately bounce back. If it's approaching a cliff, the signals all of a sudden get lost. This is how Roomba knows to head the other way. When Roomba knocks into something, its bumper retracts, activating mechanical object sensors that tell Roomba it has encountered an obstacle. It then performs (and repeats) the sequential actions of backing up, rotating and moving forward until it finds a clear path.

Render the text: Electronic Devices for the home.

 

UNIT 3

Pre-text exercises:

1. Make the collocations with the following words:Do, keep, make, pay, save

Business, a difference, interest, space, cash, a promise, quiet, money, a mistake, energy, the housework, attention, time, the cooking, a noise, control

Find the Ukrainian equivalents for the following English words and word

combinations :

a) burglar alarm, part of the circuit, opposite charge, a flashlight, detect, the act of intrusion, a magnetic sensor, a battery, a magnet

b) охоронна сигналізація; магніт; виявляти; магнітний датчик, чутливий елемент; ручний електричний ліхтар; частина схеми; протилежний заряд; акт втручання; акумулятор

3. Which of these words from the list are similar in your language? Do they mean the same? Say what words in the Ukrainian language help you to guess their meaning:

Most, electricity, act, category, sensor, a magnet, slide, control, box, monitor, glass, opposite, sort

Read the supplementary text, translate and entitle it.

If you want something done right then do it yourself. Have you heard this saying? I'm sure that you have and while some things are better left up to the professionally trained, there is no good reason why you couldn't install your own do it yourself alarm system. In fact there are security alarm kits at the Home Security Store just waiting for you to buy it right now as we speak. So what are you waiting for?

If you don't have a burglar alarm system, you need one. Here's why, you work hard to make money to buy a home, and pay a mortgage, and have a car, and have nice things, and so your family can also have nice things, and it could all be gone in a blink of an eye. Protect what’s yours and if you can't afford a big alarm system then install one yourself. Sure insurance might protect your home and your valuables but your family might never feel safe again.

You can do it yourself and be well protected. If you can handle a drill then you can install a do it yourself burglar alarm system in your home or office. Save money and protect your family at the same time, get a do it yourself burglar alarm system today and start protecting your family by tonight.

Recent studies suggest that homes without alarm systems are three times more likely to be burglarized than homes with alarm systems. Your household is probably already among the growing number of families who feel the peace of mind of having an alarm system in their home.

Most standard alarm systems cover the basics: a keypad, door and window sensors, and motion detectors. While these components offer a great deal of protection for your home, you may want to upgrade your current alarm system with some of the latest in security technology.

Render the text: How Burglar Alarms Work

 

UNIT 4

Pre-text exercises:

1. Fill in the blanks confusing words and memorize them:

Hear, listen, see, look, watch

1. Hey John! Can you… that sound? 2. Do you like to …to Rock music? 3. The children …to the teacher carefully. 4. Can you speak a little louder? I can't … you. 5. That's good to … 6. You can't… far in this fog. 7. Denny and Phil… good tonight. 8. Did you …Coronation Street yesterday evening? 9. Can you …the blue car on the left? 10. … you tomorrow, if nothing comes in between. 11. It … like rain, doesn't it? 12. Hey, what's wrong? You really … unhappy.

2. Find the Ukrainian equivalents for the following English words and word combinations:

a) a visible range, а widespread use, the spectrum, unfortunately, light bulbs, candles, central heating system, radiates Infra-Red light, in a particular frequency.

b) свічі; електричні лампи; спектр; випромінює інфрачервоне світло; системи центрального опалення; видимий діапазон; на жаль; широке використання; з відповідною частотою.

3. Translate the following words and word combinations into English:

дистанційне управління, відео обладнання, широко розповсюджений, досить легко, певний колір, найяскравіше джерело, власні проекти, без помилок, більш вживане, центральне опалення

Render the text: IR Remote Control Theory.

 

UNIT 5

Pre-text exercises:

1. Fill in the blanks with the following confusing word: accept / except, past / passed,affect / effect, dessert / desert, further/ farther, well / good, lie/ lay, two/ to/ too.

1. All of the soldiers___my brother are out of step. 2. Please ___ this pot of Mom's chicken soup. 3. You may keep all of his gifts ___ the ring. 4. That there are other universes is now an ___ scientific fact. 5. Weather conditions ____ many people's moods. 6. Crossing wire A to wire B will produce an explosive ___. 7. The politician wanted to ___ a change in the system. 8. Karen said that her chocolate ___ was delicious. 9. The world's largest hot desert is the Sahara ___. 10. I wish the professor had discussed this __. 11. Perhaps the poem would be better if the poet had provided ___detail. 12. A little bit of water in the mixture makes the paint go ___ . 13. Most students write ___ by the time they finish high school. 14. That was a ___ report that you gave yesterday. 15. Unfortunately, I didn't hear your instructions very ___.16. After I get home from work, I often ___ down for a nap before dinner. 17. Please ____ the papers on Mr. Hart's desk. 18. Write this essay in the ___ tense. 19. By the time I saw him, he had already ___ me. 20. Are you only taking ___ classes? 21. Please don't ask me ___ come. 22. Now, now, don't study ___ often.

Render the text: Radar

 

Read the text and translate it: A Laser

A laser is a device that emits light (electromagnetic radiation) through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation. The emitted laser light is notable for its high degree of spatial and temporal coherence. Spatial coherence typically is expressed through the output being a narrow beam which is diffraction-limited, often a so-called "pencil beam."

Laser beams can be focused to very tiny spots, achieving a very high irradiance. Or they can be launched into a beam of very low divergence in order to concentrate their power at a large distance. Temporal coherence implies a polarized wave at a single frequency whose phase is correlated over a relatively large distance along the beam. A beam produced by a thermal or other incoherent light source has an instantaneous amplitude and phase which vary randomly with respect to time and position, and thus a very short coherence length.

A laser which produces light by itself is technically an optical oscillator rather than an optical amplifier as suggested by the acronym. It has been humorously noted that the acronym LOSER, for "light oscillation by stimulated emission of radiation," would have been more correct. With the widespread use of the original acronym as a common noun, actual optical amplifiers have come to be referred to as "laser amplifiers", notwithstanding the apparent redundancy in that designation.

A laser consists of a gain medium inside a highly reflective optical cavity, as well as a means to supply energy to the gain medium. The gain medium is a material with properties that allow it to amplify light by stimulated emission. In its simplest form, a cavity consists of two mirrors arranged such that light bounces back and forth, each time passing through the gain medium. Typically one of the two mirrors, the output coupler, is partially transparent. The output laser beam is emitted through this mirror. Light of a specific wavelength that passes through the gain medium is amplified (increases in power); the surrounding mirrors ensure that most of the light makes many passes through the gain medium, being amplified repeatedly. Part of the light that is between the mirrors passes through the partially transparent mirror and escapes as a beam of light. The process of supplying the energy required for the amplification is called pumping.

The energy is typically supplied as an electrical current or as light at a different wavelength. Such light may be provided by a flash lamp or perhaps another laser. Most practical lasers contain additional elements that affect properties such as the wavelength of the emitted light and the shape of the beam. The gain medium of a laser is a material of controlled purity, size, concentration, and shape, which amplifies the beam by the process of stimulated emission. It can be of any state: gas, liquid, solid or plasma. The gain medium absorbs pump energy, which raises some electrons into higher-energy quantum states. Particles can interact with light by either absorbing or emitting photons. Emission can be spontaneous or stimulated. In the latter case, the photon is emitted in the same direction as the light that is passing by. When the number of particles in one excited state exceeds the number of particles in some lower-energy state, population inversion is achieved and the amount of stimulated emission due to light that passes through is larger than the amount of absorption. Hence, the light is amplified. By itself, this makes an optical amplifier. When an optical amplifier is placed inside a resonant optical cavity, one obtains a laser.

Post-text exercises:

1. Put the words in the right order to make a sentence:

1. Some, lasers, power, on, applications, of, constant, depend, a, whose, output, over, is, time, beam. 2. The, laser, mechanism, emission, producing, radiation, in, a, of, on, relies, stimulated. 3. The, the, the, of, for, is, process, supplying, called, energy, required, amplification, pumping. 4. Albert, and, Einstein, established, for, the, the, the, theoretic, foundations laser, maser. 5. Solid-state, glass, which, lasers, that, use, a or, rod, is, "doped", with, ions, energy, provide, the, required, crystalline, states. 6. The, emitted, output, beam, through, laser, is, this, mirror.7. The, which, absorbs, some, pump, energy, higher-energy, quantum, raises, electrons, into, gain, medium, states.

8. Particles, emitting, by, can, with, either, absorbing, or, interact, light, photons. 9. The, the, the, process, for, is, of, supplying, energy, required, pumping, amplification, called.

2. Fill in the blanks with the following words:

Device, wavelength, LOSER, coherence, amplitude, pumping, spots, cavity, beam.

1. A laser is a… that emits light. 2. The output laser … is emitted through the mirror. 3. The process of supplying the energy required for the amplification is called….4. A laser consists of a gain medium inside a highly reflective optical…5. The energy is typically supplied as an electrical current or as light at a different….6. Laser beams can be focused to very tiny …, achieving a very high irradiance. 7…., for "light oscillation by stimulated emission of radiation," would have been more correct.8. Temporal … implies a polarized wave at a single frequency. 9. A beam has an instantaneous ….

3. Complete the following sentences, using active vocabulary:

1. Particles can interact with light by … 2. Most practical lasers contain additional elements that affect properties such as … 3. The emitted laser light is notable for its high degree of … 4. Laser beams can be focused to very tiny spots, achieving…

5. … that affect properties such as the wavelength of the emitted light and the shape of the beam.6. …, for "light oscillation by stimulated emission of radiation," would have been more correct. 7. The surrounding mirrors ensure that most of the light makes many passes through … 8. Part of the light that is between the mirrors passes through …

9. Temporal coherence implies a polarized wave at a single frequency whose phase is ...

4. Say if the following statements are true or false:

1. Light of a specific wavelength that passes through the gain medium is not amplified.

2. Laser is light oscillation by stimulated emission of radiation. 3.The gain medium of a laser is a material of controlled purity, size, concentration, and shape. 4. A laser consists of a gain medium inside a highly reflective optical cavity. 5. There are no lasers which are single spatial mode and consequently their light beams diverge more than required by the diffraction limit. 6. The output laser beam is emitted through the optical cavity. 7. Particles of electrons can’t interact with light. 8. A laser consists of a gain medium inside a flash lamp.

5. Answer the following questions:

1. What is a laser? 2. What is the gain medium of a laser? 3. Can particles of electrons interact with light? 4. Is the output laser beam emitted through the mirror? 5. Does laser consist of a gain medium inside a highly reflective optical cavity? 6.When is the energy supplied? 7. Is photon emitted in the same direction as the light that is passing by? 8. Does laser produce light by itself?

6. Match the first part (1-5) of the sentence with the second part (a-e) :

1. The emitted laser light ...

2. A beam produced by a thermal or other incoherent light source ...

3. Pumping can interact with light by …

4. Particles have …

5. Emission ...

6. The gain medium ...

7. Stimulated emission is …

8. An optical amplifier is …

9. A light beam or beam of light is ….

a) … a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal.

b) … the process by which an atomic electron (or an excited molecular state) interacting with an electromagnetic wave of a certain frequency.

c) … an instantaneous amplitude and phase which vary randomly with respect to time and position.

d) … a narrow projection of light energy radiating from a source into a beam.

e) … is notable for its high degree of spatial and temporal coherence.

e) … is the process of supplying the energy required for the amplification is called.

f) … is a material with properties that allow it to amplify light by stimulated emission.

g) … can be spontaneous or stimulated.

h) … either absorbing or emitting photons.

7. Read the supplementary text, translate and entitle it:

Many scientific, military, medical and commercial laser applications have been developed since the invention of the laser in the 1958. The coherency, high monochromaticity, and ability to reach extremely high powers are all properties which allow for these specialized applications. In science, lasers are used in many ways, including: spectroscopy, atmospheric remote sensing, holographic techniques . Laser based LIght Detection And Ranging (LIDAR) technology has application in geology, seismology, remote sensing and atmospheric physics. Lasers have been used aboard spacecraft such as in the Cassini-Huygens mission. In astronomy, lasers have been used to create artificial laser guide stars, used as reference objects for adaptive optics telescopes.

Most types of laser are an inherently pure source of light; they emit near-monochromatic light with a very well defined range of wavelengths. By careful design of the laser components, the purity of the laser light (measured as the "linewidth") can be improved more than the purity of any other light source. This makes the laser a very useful source for spectroscopy.

Render the text: Laser

UNIT 2

Pre-text exercises:



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