01-04-2020-Дедушенко И.С.Обучение чтению и устной речи на английском языке (1171845), страница 4
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Derive a formula expressing the kinetic energy of an objectin terms of its momentum and mass.3 Two people in a rowboat wish to move around withoutcausing the boat to move. What should be true about their totalmomentum? Explain.4. You are driving your car, and you hit a brick wall head on,at full speed. The car has a mass of 1500 kg. The kinetic energyreleased is a measure of how much destruction will be done to thecar and to your body.
Calculate the energy released if you aretraveling at (a) 40 km/hr, and again (b) if you’re going 80 km/hr.What is counterintuitive about this, and what implication doesthis have for driving at high speeds?5. All stars, including our sun, show variations in their lightoutput to some degree. Some stars vary their brightness by afactor of two or even more, but our sun has remained relativelysteady during the hundred years or so that accurate data havebeen collected. Nevertheless, it is possible that climate variationssuch as ice ages are related to long-term irregularities in the sun’slight output.
If the sun was to increase its light output evenslightly, it could melt enough Antarctic ice to flood all theworld’s coastal cities. The total sunlight that falls on Antarcticaamounts to about 1 × 1016 watts.Grammar and vocabulary revisionEx. 1. Study the meanings of due, be due to and due to andtranslate the sentences.Due (to) adj — соответствующий, надлежащий, вызванный, обусловленный.Be due to — быть обусловленным, являться следствием,быть разработанным, предложенным.Due to prep — благодаря, из-за, вследствие (syn.
becauseof, on account of, owing to, in view of, thanks to, by/in virtue of,consequent on).221. Due consideration must be given to missile performancerequirements.2. No difference due to n–p scattering in the target was found.3. Coincidences arise due to second-order effect.4. A due explanation of the phenomenon of radioactivity wasfirst given by the Curies.5. This phenomenon was found to be due to the lowering ofthe temperature down to –200 C.6. An up-to-date apparatus, due to Frankenburg, is shown inFig. 10.Ex. 2.
Insert “due to” or “to be due to”.1. The errors … careless analysis.2. We shall discuss the errors … the scattering of rays.3. The physical properties of metals … relatively free mobileelectrons.4. The problem could be solved … very careful investigations.5. High yields were obtained … extremely pure startingproducts.6. Part of the filtering action … mechanical properties ofcrystals.7.
… its motion around the Sun the Earth will representdifferent systems of inertia.8. The quantum theory … Planck.9. The discovery of radioactivity … pure accident.10. Some misunderstanding … the complexity of the problem.Ex. 3. Make up singular-rplural pairs.Foci, quanta, maximum, analyses, vacua, axis, maxima,radius, genii, radii, locus, nuclei, analysis, focus, hypothesis,criteria, nucleus, quantum, crisis, theses, momenta, axes,synthesis, criterion, phenomena, genius, species, loci, hypothesis,thesis, momentum, syntheses, phenomenon, vacuum, species.23Ex.
4. Translate the following sentences into Russian,paying attention to the form and function of the Participle.1. Electrons forming an atom are in motion.2. Having considered the problem involved they arrived at adefinite conclusion.3. Following the method involved we found it to be effective.4. The results obtained agree with those predicted by thetheory.5. Having been separated from a mixture the substance wasinvestigated under the microscope.6.
When heated to a high temperature in a vacuum a metalgives off free electrons.Ex. 5. Translate the following sentences into Russian,paying attention to the Absolute Participial Construction.1. An electron leaving the surface, the metal becomespositively charged.2. With the experiments carried out, they started newinvestigations.3. A magnet is broken into two parts, each piece becoming amagnet with its own pair of poles.4. All the liberated electrons having reached the anode,saturation occurs.5. The temperature of the conductor being raised, the motionof electrons also increases.6. Hydrogen is the simplex substance, atoms of all otherelements having a more complex structure.7.
The nucleus of an ordinary hydrogen atom consists of oneproton, with one electron moving around it.8. All these elements radioactive, their atoms being unstableand undergoing spontaneous disintegration.9. The pressure being reduced within the tube, certainremarkable phenomena occur.10.
Having applied a positive pulse of voltage to the controlelectrode, we made the valve conducting.24Ex. 6. Translate the following sentences into English,paying attention to the Participle and the Absolute ParticipialConstructions.1. Двигаясь по кругу с одинаковой скоростью, телонепрерывно изменяет свое направление.2. После того как прибор прошел тщательное испытание,его ввели в эксплуатацию.3. Луч лазера имеет почти неограниченные возможностиприменения в промышленности.4. Нейрон — частица, имеющая одинаковую массу спротоном, но не несущая электрического заряда.5. Так как измерения производились неточнымиприборами, данные были ненадежными.6. Испытываемое оборудование требует дальнейшегоусовершенствования.7. Когда атом возбужден, он испускает квант излучения.8. Получивнеобходимуюэнергию,электроныионизируют атомы.9.
После того как информация обработана, выходноеустройство передает окончательный результат.25Unit 3. VIBRATIONSMemorize the following vocabulary to text 3A.conjure v — 1. показывать фокусы; 2. вызывать ввоображении (— up)link v — соединять, связыватьto be linked to — быть привязанным к чему-либоpitch n — высота тона, звукаrepetition n — повторениеrepetitive adj — повторяющийсяseam n — шовseamless adj — бесшовныйrandom adj — произвольный, случайныйrandomly — произвольноat random — наугад, наобумprevail v — преобладать, господствоватьprevail over — одолевать, торжествовать над кем-либоprevail on — убедить кого-либоprevalent adj — распространенный, преобладающийText 3A.
VibrationsRead and translate the text.Dandelion. Cello. Read those two words, and your braininstantly conjures a stream of associations, the most prominent ofwhich have to do with vibrations. Our mental category of“dandelion-ness” is strongly linked to the color of light wavesthat vibrate about half a million billion times a second: yellow.26The velvety throb of a cello has as its most obvious characteristica relatively low musical pitch — the note you are spontaneouslyimagining right now might be one whose sound vibrations repeatat a rate of a hundred times a second.Evolution has designed our two most important senses aroundthe assumption that not only will our environment be drenchedwith information-bearing vibrations, but in addition thosevibrations will often be repetitive, so that we can judge colors andpitches by the rate of repetition.Granting that we do sometimes encounter nonrepeating wavessuch as the consonant “sh,” which has no recognizable pitch, whywas Nature’s assumption of repetition nevertheless so right ingeneral?Repeating phenomena occur throughout nature, from theorbits of electrons in atoms to the reappearance of Halley’sComet every 75 years.
Ancient cultures tended to attributerepetitious phenomena like the seasons to the cyclical nature oftime itself, but we now have a less mystical explanation. Supposethat instead of Halley’s Comet’s true, repeating elliptical orbitthat closes seamlessly upon itself with each revolution, we decideto take a pen and draw a whimsical alternative path that neverrepeats. We will not be able to draw for very long without havingthe path cross itself. But at such a crossing point, the comet hasreturned to a place it visited once before, and since its potentialenergy is the same as it was on the last visit, conservation ofenergy proves that it must again have the same kinetic energy andtherefore the same speed. Not only that. The comet’s direction ofmotion cannot be randomly chosen, because angular momentummust be conserved as well.
Although this falls short of being anironclad proof that the comet’s orbit must repeat, it no longerseems surprising that it does.Conservation laws, then, provide us with a good reason whyrepetitive motion is so prevalent in the universe. But it goesdeeper than that. Up to this point in your study of physics, Ihave been indoctrinating you with a mechanistic vision of the27universe as a giant piece of clockwork. Breaking the clockworkdown into smaller and smaller bits, we end up at the atomiclevel, where the electrons circling the nucleus resemble — well,little clocks!From this point of view, particles of matter are thefundamental building blocks of everything, and vibrations andwaves are just a couple of the tricks that groups of particles cando. A chain of discoveries initiated by Albert Einstein at thebeginning of the 20th century led to the realization that the socalled subatomic “particles” were in fact waves.
In this newworld-view, it is vibrations and waves that are fundamental, andthe formation of matter is just one of the tricks that waves can do.(2608)Text 3B. Period, Frequency, and AmplitudeRead the text and render it.A spring is our most basic example of a vibration. With noforces on it, the spring assumes its equilibrium length. It can bestretched, or compressed.
Imagine that the spring is attached to awall on the left and to a mass on the right. If now the mass is hitwith a hammer, it oscillates. If we assume that the mass slidesback and forth without friction and that the motion is onedimensional, then conservation of energy proves that the motionmust be repetitive.When the block comes back to its initial position again, itspotential energy is the same again, so it must have the samekinetic energy again. The motion is in the opposite direction,however. Finally, it returns to its initial position with the samekinetic energy and the same direction of motion. The motion hasgone through one complete cycle, and will now repeat forever inthe absence of friction.
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