Words and word combinations to be remembered

put forward – выдвигать, предлагать	increase – возрастать, увеличивать	harness – использовать. приспосабливать
alter – менять, изменять	decrease – уменьшаться, убывать	capture – поглощать, завладеть
regard – касаться, иметь отношение	destroy – разрушать, уничтожать	constrain – заставлять, обязывать, сдерживать
convert – превращать, переводить, трансформировать	fuse – объединяться, сливаться, смешиваться	remain – оставаться
support – поддерживать, подтверждать	expend – тратить, расходовать	capacity for doing smth – способность ч-л делать, мощность, производительность

Ex. 1. Translate the following sentences and explain the use of tenses in them:

1. Whenever work is done, energy of some other form is used up. 2. If too much fuel is supplied to the engine, more kinetic energy will be produced than is being used up, and the car will go faster. 3. If the car is slowed down by application of the brakes, the lining of these bring very large forces of friction into play and kinetic energy is destroyed in overcoming these forces and liberated as heat. 4. The electrical energy is converted into heat and light. 5. The loudspeaker is made to vibrate and energy in the form of sound results.

Ex. 2. Choose the right word:

1. What do you know about Einstein’s work on the theory of (relativity, relativism)? 2. This scientist (put out, put forward) his theory two centuries ago. 3. The mass and energy can be (supported, converted) from one to the other. 4. The law of conservation of (matter, energy) states that the total quantity of matter in the universe is fixed and cannot be increased or decreased. 5. The law of conservation of energy affirms that the total quantity of energy in the universe is likewise (constant, distinct) and can be neither created nor destroyed. 6. These two laws have become (used, fused) into one. 7. One type of energy has been (transformed, simplified) into another. 8. Whenever energy in one form is (separated, expended), an equal amount of energy in some other form takes its (part, place). 9. We have different (units, laws) in which various forms of energy are measured. 10. The law of the conservation and transformation of energy is one of the (fundamentals, constants) of physics.

Ex. 3. Make up all possible questions to these sentences:

1. The rate at which machines can work is called their power rating and is usually given in horsepower or watts. 2. Large machines may have ratings of several thousands of horsepower. 3. The forces of nature are capable of working at tremendous rates for very short intervals of time.

Ex. 4. Make up sentences with the following words and word combinations:

Theory of relativity, put forward, regarding mass and energy, separate, distinct, simplified, were accepted, constant, the law of conservation, electrical energy, quantity, a number of experiments.

Ex. 5. Fill in the blanks:

1. Einstein’s work … our ideas regarding mass and energy.

2. Einstein … our picture of the universe.

3. His view … by a number of experiments.

4. These two laws … fused into one.

5. We have seen a number of cases where one type of energy … into another.

6. Whenever energy in one form is … , an equal amount of energy in some other form … .

7. The transformation of energy is never 100% efficient because we cannot … .

8. Energy can be defined as … .

9. The energy transformations are constrained by a fundamental principle, … principle.

10. The conservation of energy is a statement that the quantity called energy remains … regardless of when it is evaluated or what processes go on between successive evaluations.

Ex. 6. Answer the following questions:

1. What kind of theory did Einstein put forward? 2. What has his view been supported by? 3. What does the law of conservation of matter state? 4. What does the law of conservation of energy affirm? 5. Can one type of energy be transformed into another? 6. Is the actual amount of energy the same as before the conversion of work into heat? 7. Why is the transformation of energy inefficient in every situation? 8. Is it possible to convert the chemical energy of coal directly into electrical energy? 9. What does the principle “Energy can neither be created nor destroyed” mean? 10. Could you give any examples of transformations of energy from one form into another?

Ex. 7. Translate into English:

Эйнштейн выдвинул теорию относительности. Он показал, что масса и энергия могут переходить друг в друга. До того как была выдвинута эта теория, физики признавали два закона: закон сохранения вещества и закон сохранения энергии. Они утверждали, что общее количество вещества и энергии в мире постоянно. В свете теории относительности эти два закона слились в один. Один вид энергии переходит в другой, но общее количество энергии остается таким же, как и до перехода.

UNIT13. 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.

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. These 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^-¹º 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 soon 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 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.