Exercise 2 Answer the following questions. 1. What is the text about?
1. What is the text about? 2. How does the sun’s energy manifest itself? 3. When could useful energy from the sun be generated? 4. What is the most ancient of man’s activated processes? 5. Where does photo-electricity find its application? 6. When is the intensity of the sun’s rays at its maximum and when is it at its minimum? 7. What is the effective way to minimize the loss of energy from the heated surface? 8. What is the simplest collector of solar energy? 9. What for can heat from the sun be used? 10. What was the secret of the Egyptian statue?
Exercise 3 Translate and memorize the following expressions from the text.
Photo-chemical effects, solar energy, to generate useful power, crude device, solar evaporation of sea water, light-meter, thermal solar process, surrounding air, surface temperature, absorbed heat, radiation intensity, loss of energy, heated surface, glass-like material, air space, flat plate, transparent sheets of glass, portable solar heater, distillation of sea water, high-pressure boilers, to track the sun.
Exercise 4 Find synonyms among the following words.
Solar power (n), manifest (v), earliest (adj), middle (adj), generate (v), application (n), apply (v), common (adj), similar (adj), occasion (n), prevent (v), loss (n), probably (adv), purpose (n), achieve (v), sun’s energy (n), announce (v), ancient (adj), average (adj), produce (v), use (n), employ (v), ordinary (adj), resembling (adj), cause (n), ward off (v), waste (n), very likely (adv), aim (n), attain (v).
Exercise 5 Write a summary of the text, presenting the content of each paragraph in 2-3 sentences. Use the expressions:
The main idea of the text is … The text deals with the one of the most important (urgent) issues … Much attention (consideration) is given to (classification, description) … It focuses on the matter of … The text gives an overview of … The text is mainly concerned with … The aim of the survey is to show (demonstrate, find) … Particular emphasis is given to the analysis of… The text gives a detailed analysis of (reports on) … To sum up … In conclusion …
Индивидуальное задание для студентов заочного отделения к курсу
«Английский язык»
Вариант № 23/3c
Exercise 1 Read the text and translate it in written form.
Atoms
(1) The story of atoms goes back to the time of Greek thinker Democritus (about 460-370 B. C.). He thought all substances to be made up of tiny particles or atoms which could not be further divided. He thought that there were only four elements: fire, earth, air and water. The theory of the ancient Greeks was not confirmed by further discoveries in science.
(2) John Dalton (1766-1844) like Democritus put forward the idea that all substances were made up of atoms, but unlike Democritus he believed that there were many elements. Some very wonderful discoveries have been made by the end of the 19th century.
(3) Everything including man is made up of atoms. They are about a hundredth of a millionth of an inch across, there being many millions of them in a single breath of air. Once people thought them to be hard, indivisible spherical balls, however it is now known that they are made up of even smaller particles.
(4) Bohr believes the atom to consist of two parts: a massive central core or nucleus in which the charge of positive electricity was concentrated and smaller particles called electrons that surrounded the core and in which the charge of negative electricity was concentrated.
(5) This model of the atom resembled our solar system. The nucleus could be compared to the sun and the electrons could be compared to the planets that circle about the sun.
(6) The nucleus and electrons in the atom are held together by the mutual electrical attraction between the positive nucleus and the negative electrons. The positive and negative electrical charges neutralize each other so that the atom as a whole is electrically neutral.
(7) In Bohr’s model the nucleus was made up of protons. Each proton carried one positive charge of electricity. Each electron circling about the nucleus carried one negative charge of electricity. For the atom to be electrically neutral, therefore, the number of protons must be equal to that of electrons.
(8) In Bohr’s atomic theory it was the number of protons in the nucleus that determined which element the atom was. Hydrogen, for example, is the simplest atom. It has one proton in its nucleus, and there is one electron circling about the nucleus. The next simplest atom is the helium atom. This atom has two protons in its nucleus and two electrons circling about the nucleus.
(9) Modern atomic theory says that each atom has at its centre a nucleus consisting of protons and neutrons. Electrons are orbiting the nucleus. Every atom consists almost entirely of empty space, its size being indicated approximately by the orbit of the outermost electron. The nucleus and electrons are each about a tenth of a millionth of a millionth of an inch across. Most of the mass of an atom is in the nucleus.
(10) Electrons are extremely light as compared with protons and neutrons which have nearly the same mass; the mass of an electron is only about 1/1840 the mass of a proton.
(11) Electrons are negatively charged and are held in the atom because protons have an equal but positive charge. Neutrons have no electric charge. The atom is electrically neutral, so that the number of orbital electrons it has must be equal the number of protons in the nucleus. This number which is important because it ‘identifies’ a chemical element, is called the atomic number and is sometimes represented by the symbol z.
(12) Nitely kinds of atoms with varying chemical properties occur naturally on the earth. They are chemical elements, such as hydrogen, oxygen, carbon, gold, uranium and so on.