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Match the notions and their definitions

Поиск

a. Scattering 1. a process of making waves of light, etc. vibrate in a single direction

b. Absorption 2. the sound or other vibration produced in an object by sound or vibrations of a similar frequency from another object

c. Radar 3. the greatest distance that a wave, especially a sound or radio wave, vibrates

d. Resonance 4. a process of a liquid, gas or other substance being taken in

e. Polarization 5. a process of spreading in different directions

f. Coherence 6. the situation in which all the parts of smth fit together well

g. Software package 7. a small colored mark or spot on a background of a different color

h. Speckle 8. a set of related programs for a particular type of task, sold and used as a single unit

i. Amplitude 9. a system that uses radio waves to find the position and movement of objects

 

1.3. Find the Russian equivalents of the following expressions in the text above:

1. Наиболее распространенный вид

2. Общепринятое название

3. Показатель преломления

4. Верхний предел

5. Ослабление излучения

6. Произвольная форма

7. Метод конечных элементов

8. Неясное, малоизученное явление

9. Распространяться сквозь среду

10. Применять модель

11. Локальный максимум

12. Случайные флуктуации

13. Явление интерференции

14. Слабая локализация

15. Узкий/ ограниченный угловой диапазон

16. Распределение в пространстве

17. Точечный источник

1.4. Find the synonyms to the following words in the text above:

 

Noun Verb Adjective/ adverb
exhaustion/ depletion reason/ motive rate/ speed displacement to promote/ encourage to explain/ clear up to alter to evaluate traditional very/ specifically different/ various technically complicated

 

Translate the sentences below paying attention to concessive clauses

As (though)... - Хотя и; как бы ни; как ни

 

Example: Difficult as ii was, the author tried to cite the data.

Хотя это и трудно, автор пытался привести данные.

 

1. Incomplete though the information about the constitution of the atmosphere of the planet may be it is still of value.

2. This hypothesis, surprising as it may seem at first, contains a considerable element of truth.

3. Important though the question may be in itself the debate on the subject went far beyond its original bounds.

4. Safe though an alternative method seemed thus far it was not extended to electronic states of low density plasma.

5. Difficult though it is to observe the surface of Mercury, it is more difficult to obtain certain evidence of the atmosphere.

6. Acceptable though these models proved in a general case they also suffer from shortcomings in the data available.

7. Strange as it may seem, the theory of numbers can be called an empirical or even experimental science.

1.6. Prepare short reports to explain the following topics:

· Brillouin scattering

· Raman scattering

· X-ray scattering

· Compton scattering

· LIDAR

· Rayleigh scattering

· Mie scattering

· Young's interference experiment

· Anderson localization

 

TEXT 2

Before reading the text below explain the following notions.

1. attenuation

2. the Beer-Lambert law

3. absorption

4. spectroscopy

5. deforestation

6. global warming

7. albedo

Absorption in Physics

In physics, absorption is the process by which the energy of a photon is taken up by another entity, for example, by an atom whose valence electrons make transition between two electronic energy levels. The photon is destroyed in the process. The absorbed energy may be re-emitted as radiant energy or transformed into heat energy. The absorption of light during wave propagation is often called attenuation.

The absorbance of an object quantifies how much light is absorbed by it (not all photons get absorbed; some are reflected or refracted instead). This may be related to other properties of the object through the Beer-Lambert law.

For most substances, the amount of absorption varies with the wavelength of the light, leading to the appearance of color in pigments that absorb some wavelengths but not others. For example, an object that absorbs blue, green and yellow light will appear red when viewed under white light. More precise measurements at many wavelengths allow the identification of a substance via absorption spectroscopy.

 

The specific phenomena involving absorption of electromagnetic radiation at the Earth's surface have several important aspects. These phenomena include regulating the temperature of the Earth's crust, surface waters and lower atmosphere. Changes in the Earth's crust such as glaciation, deforestation, polar ice melting, will necessarily alter the quantity and wavelength selectivity of electromagnetic absorption at the Earth's surface; correspondingly, changes in climate such as global warming may accompany changes in electromagnetic absorption or its inverse, the albedo. Regulation of the temperature of surface waters has been analyzed with respect to the influence of electromagnetic radiation absorption, indicating the effects of total solar insolation and the local albedo.

 

Absorption refers to the absorption of sound waves by a material. The absorption is the "missing piece", when comparing the total reflected and transmitted energy with the incident energy.

It is the property of a material that changes acoustic energy into usually heat energy. A material or surface that absorbs sound waves does not reflect them. Absorption of a given material is frequency dependent as well as being affected by the size, shape, location, and mounting method used.

A good sound absorber is normally a porous material e.g. mineral wool, glass wool, but also Micro perforated plates work as sound absorbers.

Absorption is not a single mechanism of sound attenuation. Propagation through a heterogeneous system is affected by scattering as well.

2.2. Match the words to form collocations:

 

 

 

2.3. Translate the sentences below paying attentionto the emphatic constructions.

 

1. It was only very gradually that the ideas of atoms became advanced and useful.

2. It is the "optical theorem" put in precise form by Niels Bohr that enabled us to compute the total cross section.

3. Again, it was the temperature change that turned out to be sufficient to account for an appreciable part of resistance change while the field was on.

4. It was Heinrich Hertz who in 1887 - 1888 succeeded in showing that rapidly oscillating electric charges do indeed produce electromagnetic waves.

5. Therefore one can conclude that Cygnus X-I docs comprise a black hole. At least this conclusion is the most reasonable cue.

6. Not until mechanics of fluids, mechanics of solids and applied mathematics were sufficiently advanced was ii possible io solve the main problems of fluid mechanics.

7. The first radio noise from outerspace was detected in 1930, but it was not until after the Second World War that a new branch of science, radio astronomy, was developed.

8. Not only did they collect material on the problem but they also arranged it properly.

9. Thus not only docs elastic scattering respond to the overall charge magnetic moment of the neutron but also reveals what is going on inside.

10. Not only did the newly discovered electron provide an entity (сущность, нечто реально существующее) which was assumed to be a constituent of all atoms, but it also provided a natural unit of electricity.

11. Perhaps, never before has been achieved more extensive and complete cooperation among scientists as in this task to prevent war.

12. There is no denying the fact that never before was there any discrepancy in our work between theoretical and experimental data.

13. No sooner had the existence of the electron been established than many phenomena were nicely accounted for.

14. No sooner did the electron flow through the coil cease than the magnetic field collapsed and the iron was no longer magnetized.

15. This circuit will not be suitable for many applications, neither will it greatly facilitate the attainment of the amplified signal.

16. Mercury is not known to have atmosphere, nor is a permanent gaseous envelope expected to occur under the conditions existing on the planet.

17. The history of modern optics is related to two theories of light. Neither concept has been rejected. Nor is there any paradox in the occurrence of both wave and particle theory of light.

TEXT 3

For questions 1-6, read the text below and decide which answer (A, B, C or D) best fits each gap.



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