Англ.мова

Newton‟s contribution to the world science was a decisive one in finding the mathematical method for converting physical principles into quantitatively calculable results confirmable by observation, and, conversely, to arrive at the physical principles from such observations.

The instrument by which he did this was the infinitesimal calculus which he used to solve vital questions in physics and taught others to do the same.

By its use it is possible to find the position of a body at any time by knowledge of the relations between that position and its velocity or rate of change of velocity at any other time. In other words, once the law of force is known, the path can be calculated. Applied inversely, Newton‟s law of gravitational force follows directly from Kepler‟s law of motion.

Mathematically they are two different ways of saying the same thing; but whereas the laws of planetary motion seem abstract, the idea of a planet held in its course by a powerful gravity attraction is understandable, even if the gravitational force itself remains a complete mystery.

The calculus, as developed by Newton, could be used and was used by him for solving a great variety of mechanical and hydrodynamic problems. It immediately became the mathematical instrument for all understanding of variables and motion, and hence of all mechanical engineering, and remained almost the exclusive one until well into the present century. In his Principia

Newton did far more than establish the laws of motion of the planets. His object

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was certainly to demonstrate how universal gravity could maintain the system of the world. But he wished to do this not in the old philosophical way but in the new, quantitative, physical way. He destroyed all previous philosophic conceptions, old and new, and established his own not only the correct but also the most accurate way of accounting for the phenomena. In a word, Newton established, once and for all, the dynamic view of the universe instead of the static one and showed that the universe was regulated by simple mathematical laws.

Though Newton used the calculus in arriving at his results, he was very careful in his Principia and did all the work in the form of classical Greek geometry understandable by other mathematicians and astronomers. The immediate practical consequence of its publication was to provide a system of calculation enabling the positions of the moon and planets to be determined far more accurately on the basis of a minimum of observations. Three observations, for instance, were sufficient to fix the position of a celestial object for an indefinite future. The proof of this was given soon after Newton‟s time by his friend Halley in his famous comet, whose return he successfully predicted on the basis of Newton‟s theories.

Exercise 4. Complete the following sentences using information from the text. Try not to look into the text.

1.Newton‟s Principia was published ….

2.In it Newton developed ….

3.The importance of the theory of gravity can only be compared to ….

4.In this work Newton established … and showed ….

5.Newton developed the mathematical method for ….

6.By means of his infinitesimal calculus it is possible to find ….

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7.Newton‟s calculus can be used for solving a great variety of problems in such fields as ….

8.The first proof of his theory was ….

Exercise 5. Agree or disagree with the following statements. If you don‟t agree,

explain why.

1.Newton‟s book Philosophie Naturalis Principia Mathematica was published in 1687.

2.In its physical insight and its effect on scientific ideas it could be compared

only to Darwin‟s Elements.

3.The main Newton‟s instrument was the infinitesimal calculus.

4.Once the law of force is unknown, the path can be calculated.

5.The calculus, as developed by Newton, could be used and was used by him for solving a great variety of mechanical and hydrodynamic problems.

6.Newton established, once and for all, the dynamic view of the universe instead of the static one and showed that the universe was regulated by simple mathematical laws.

Exercise 6. Pretend that your partner does not know the meaning of the following word combinations. Try to explain him/her how you understand them.

Physical insight, calculable results, planetary motion, complete mystery, accurate way of doing something, gravity attraction.

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Exercise 8. Find synonyms to the given words. Make up sentences using these words.

Powerful, vital, velocity, motion, mystery, establish, consequence.

Exercise 9. You have read the text. Fill in the gaps. Try not to look into the text.

1)Mathematically Phylosophie Naturalis Principia Mathematica could only be … to Euclid‟s Elements.

2)Once the law of force is known, the path can be … .

3)Newton‟s law of gravitational force follows … from Kepler‟s laws of motion.

4)In his Principia Newton did far more than establish the laws of motion of the … .

5)Newton … all previous philosophic conceptions, old and new, and … his own way of accounting for the phenomena.

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Exercise 10. Make up your own sentences with the given words. Do this task in

writing.

1)velocity;

2)instrument;

3)accurate;

4)motion;

5)insight.

Exercise 11. Make reports on the following topics:

Newton‟s “Philosophie Naturalis Principia Mathematica”;

Darwin‟s “Origin of Species”.

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UNIT IV. THE STRUCTURE OF THE ATOM

Exercise 1. Listen to the text. State whether the following sentences are true or

false.

1.An atomic bomb exploded over Hiroshima 60 years ago today.

2.George W. Bush will attend a memorial service in Hiroshima.

3.A ceremony will remember people who died while begging for water.

4.August 6 is a holiday in Hiroshima.

5.The bomb‟s blast killed half of Hiroshima‟s population.

6.The bomb destroyed 30 per cent of the city.

7.An equal number died three days later in the Nagasaki bombing.

8.The atomic bombings of Japan brought a quicker end to WWII.

Exercise 2. Learn the new words. Work in pairs and check up your memorizing.

THE STRUCTURE OF THE ATOM

It is difficult to say definitely who was the first to say the word “atom”; perhaps, that was the ancient Greek philosopher Democritus (5-4 B.C.). The word “atom” comes from Greek and means “that which has no parts”. The atom we know is far from being solid and indivisible, but we continue to use the word to designate the smallest particle which takes part in chemical interactions.

The origin of atomic physics as a branch of science can be attributed to

Röntgen‟s discovery of X-rays. It was this discovery that enabled J. J. Thomson to complete his understanding of the generators of X-rays – the cathode rays or electrons. He found that not only did electrons striking matter generate X-rays, but that X-rays striking any kind of matter generated electrons. The discovery that electrons could be extracted from most different kinds of matter pointed to them as the substance of electricity. But this substance was made of individual particles – it was “atomic” – and it is this idea that led J. J. Thomson to take the first decisive step towards the discovery of the inner structure of the atom.

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In 1903 J. J. Thomson advanced the first hypothesis concerning the structure of the atom. He suggested that atom is electrically neutral because it contains equal numbers of positive and negative charge carriers. This carriers are uniformly distributed throughout the atom as a whole and they occupy all the space in the atom, a sphere with the radius of 10-10 metre. The Thomson‟s model is often called the plum-pudding model of the atom because the electrons which neutralize the positive charge are supposed to be scattered around in the positive charge mass like raisins in a plum-pudding.

Thomson‟s model of the atom structure was rejected, as it didn‟t account for the results of the experiments made by the Rutherford team. In 1910 two of Rutherford‟s workers, Geiger ['gaɪgə] and Marsden showed that the alpha particles, instead of going straight through thin sheets of matter were occasionally shot straight back. From this surprising result Rutherford drew a simple conclusion that the alpha particle must have hit something very small and very hard. He understood that atoms had nuclei. The nucleus was the other partner of the electron, and because the electrons were negatively charged, the nucleus must have a positive charge exactly equal to the total charge of the electrons around it. How were these electrons arranged? The problem had many strange analogies with that of the arrangement of the planets in the solar system and it pointed out to a similar solution. Rutherford‟s model of the atom was called nuclear atom or solar system atom. According to Rutherford‟s theory the positive charge carriers in the atom are not uniformly distributed throughout the atom but are concentrated in a small region at its centre with the radius which is much less than that of the atom while the electrons are revolving around the nucleus.

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Exercise 3. You have read the text. Complete the following sentences. Try not to

look into the text.

1.As a branch of science atomic physics is concerned with ….

2.Its origin may be ascribed to the discovery of ….

3.Röntgen‟s discovery of X-rays enabled J. J. Thomson to understand ….

4.Thus, in 1903 J. J. Thomson discovered the nature of … and put forward the first hypothesis concerning ….

5.According to Thomson‟s model the atom ….

6.The word “atom” comes from … and means ….

7.However, Thomson‟s model of the atom didn‟t account for … and therefore was ….

8.In their experiments Rutherford and his colleagues observed ….

9.Rutherford came to the conclusion that atom ….

10.Rutherford‟s model of the atom is called … because ….

Exercise 4. State whether the sentences are true or false. Explain why.

1)It is not difficult to say definitely who was the first to say the word

“atom”.

2)Atomic physics is not a branch of science.

3)Thomson took the first decisive step towards the discovery of the inner structure of the atom.

4)Thomson suggested that atom is electrically neutral.

5)According to Rutherford‟s theory the positive charge carriers in the atom are uniformly distributed throughout the atom.

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Exercise 6. Match the words with their synonyms. Translate them into Ukrainian.

Exercise 7. Find antonyms to the given words. Make up sentences with these words.

Negatively, inner, small, simple, similar, solid, continue, indivisible.

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