Words and word combinations to be remembered

skilful – опытный, квалифицированный	degree – учёная степень, диплом	feature – характерная черта, свойство, особенность
exact science – точная наука	chair – кафедра	conclusion – вывод
extend – расширять, продолжаться, длиться	influence – влияние	mechanics of the heavens – небесная механика
essential – важнейший, основной	approach – подход	pull – тянуть, притягивать
involving – касающийся	solution – решение	consider – рассматривать, считать

Ex. 1. Translate from Russian into English:

Своими руками, безуспешно, различные явления, кафедра физики и математики, курс лекций по оптике, все вопросы, касающиеся движения, дифференциальные и интегральные исчисления, теория гравитации, падение яблока, объяснить, бесконечное движение планет, основа всех расчетов, ученый, связующее звено, рассчитать силу гравитации, известный под названием.

Ex.2. Make up some questions on this text.

Ex.3. Make up the plan of this text.

Ex.4. Are these statements true or false?

1. Newton’s father was a fisherman. 2. Newton’s childhood was a happy one. 3. Newton did well at school. 4. He liked making models and toys. 5. Newton’s lecture course in geometry was very successful. 6. Newton was interested in all questions involving motion. 7. The differential and the integral calculus were developed by Descartes, his first "tutor" in science. 8. Newton assumed that the force of gravity exists only on the Earth. 9. Newton tried to explain the laws which could account for the ceaseless motion of the planets round the sun. 10. Newton’s great work Principle was published in 1687. 11. The genius scientist died very early.

Ex. 5. Say a few words about:

• The role Descartes played in Newton's life

• Newton as a scientist

• Newton's Principia and its significance for physics

• The theory of gravity

Unit4. Three states of matter

The gaseous state.

A gas is a substance which

a) has no set shape of its own; b) fills any vessel into which it is put; c) exerts a pressure on anything with which it comes into contact.

Now suppose that in a certain container there is a collection of molecules which are moving about with very high velocities in all directions. Then they will continually collide with each other, knocking each other violently aside. They will therefore keep each other at a distance and their average distance apart will be sufficiently large for the forces of attraction between them not to matter. The molecules will make full use of all the space available in the containing vessel. In their constant collisions the walls of the vessel or anything placed in their path, they will exert a pressure there. They rebound each other immediately on collision; they can exert no lasting forces of attraction and so will not take up any fixed shape of their own.

The liquid state.

A liquid is a substance which:

a) possesses a definite volume; b) has no shape of its own, but takes up the shape of that part of the containing vessel with which it comes into contact; c) if heated, it will evaporate and eventually boil, while it is cooled, it will eventually freeze and become solid.

Suppose the velocities of the molecules referred to above are by some means progressively reduced. Then the violence of their mutual collisions will steadily weaken. Soon the attractive forces will cause them to collapse together and their average distance apart to become very small. Each molecule will have little chance of escaping from the forces of attraction of its neighbouring molecules, though it can wander about amongst them. As a result, all the molecules will be weakly held together and will thereby occupy a much smaller but definite space. These are just the fundamental properties of the liquid state.

The solid state.

A solid is a substance which:

a) possesses a definite volume; b) has a fixed shape; c) shows a measure of mechanical strength which resists any effort made to change its shape.

If the motions of molecules are reduced enough, individual molecules may not be able to escape from the attractive forces of their immediate neighbours. On the average, the molecules will become closer together that they were in the liquid state – almost touching, and the forces between them will be correspondently greater. The motion of each molecule will have been reduced to a mere vibration to and fro about some fixed position in the solid structure. Molecules can no longer wander amongst one another as they could in the liquid state. Each forces its neighbours to stay in their places, and thus the collection as a whole retains its own shape. This state of affairs represents the solid state.