Fill the gaps using the derived adjectives from Ex. 9.

1.Even the historian Joseph Needham, who admired Chinese achievements in technology, confessed himself puzzled by their failure to make … progress in science.

2. Material atoms are the smallest … units of chemical compounds;

3. A principle becomes a law if what before could not be observed becomes… by the virtue of some advance in experimental technique.

4. Scientists calculate mathematically what is … in the same way as with the most common things.

5. Scientists do not worry whether what they find is ‘logical’ and … ‘or ‘possible’.

6. For decades Hawking had been debating with other scientists over the ‘information paradox’,  that was the question of whether or not data might be … from the black holes.

11. Match the symbols with the Russian and English names of elements and symbols.

Elements

1) As   2) C  3) H  4) Hg     5) Fe   6) K 7) Mn 8) N  9) Na 1 0) Pb   11) Sb  12) Sn

а) азот   б) водород в) железо г) калий д) марганец е) мышьяк

Натрий    ж) олово       з) ртуть и) свинец к) сурьма л) углерод

a) antimony   b) arsenic   c) carbon   d) hydrogen f) iron g) lead

H) manganese i) mercury j) nitrogen k) potassium l) sodium      m) tin

Fill the gaps with the names of appropriate elements. The first is done for you.

1 …C (carbon).. is non-metal. It is unique among elements because a whole branch of chemistry (organic chemistry) is devoted to it .

2. Metallic … is the main constituent of the earth crust, but it is rarely found in its core. It is found in meteorites. Its deficiency in the human body causes anemia

3.  …compounds are used in the manufacture of medicines, paints, explosives and fireproofing materials

4. … is used in roofing, water pipes, radiation shields and alloys including solder. It is added to to gasoline as antiknock agent.

5. … oxide or white arsenic is used as a poison.

6. … It is also known as quick silver. The metal is used to form amalgams, for electrodes, in barometers, thermometers.

7. The compound of… with oxygen referred to as laughing gas is used as a weak anesthetic, sometimes producing mild hysteria and as an aerosol propellant.

8. … has one natural radioactive isotope with half-life of 1.28 bln. years and can be used to date ancient rocks. The salts of this element are essential to plant life (hence their use as fertilizers) and important for animals for the transmission of impulses through the nervous system.

9. …is the sixth most common element and occurs naturally in common salt and many other important minerals such as cryolite.

10. …is used as a protective coating for steel, and in alloys including solder, bronze, pewter, Babbitt metal.

11. The  oxide  of…is used as a bleach, disinfectant and powerful oxidizing agent.

12. The atoms of … make up 90% of the universe, on earth it occurs combined with oxygen as water or with carbon as hydrocarbons (e.g. petroleum).

 

UNIT 10     PHYSICAL QUANTITIES, UNITS, CONSTANTS

 

Read the text and give headings to the numbered paragraphs.

 

Forces

1. ___ Some words in physics have a meaning that is more closely defined than the word’s meaning in everyday use. There is a multitude of words in the English language that represent force. Some examples of these words are: push, pull, hit, knock , shove, effort, load, pressure, strength, power, and vigour. In science it is essential to be careful in the use of words, so that when a word is used its meaning is clear. For instance, in the above list, some of the terms are scientifically inaccurate. Power means the wok done per time, it does not mean force. Pressure means force per unit area; this is different from force. Other words in the list are simply descriptions of particular situations where force occurs; tension, load and effort come into this category.

2.____When dealing with types of force, however, we find, surprisingly, that outside the nucleus of atoms there are only two possible types of force, which are electromagnetic and gravitational. Electromagnetic forces exist between moving or stationary charges. Since all atoms have charged particles within them, it is electromagnetic forces that bind atoms together in solids and liquids. On some occasions the electrical nature of a force is important, while sometimes the magnetic nature is important. In these cases there is not usually any problem pinpointing where the force exists.

3. ___ In the vast majority of mechanics problems, however, it is the electromagnetic forces between atoms that are of prime importance. Whenever

the atoms of one object are close to the atoms of another object, there will be a contact force between them. All forces of contact are electromagnetic forces. In the list given above push, pull, hit,   knock, shove, effort are all examples of electromagnetic forces. Tension is also a contact force, but is used in a rather special way involving internal electromagnetic between atoms in a string as well as the contact force between the string and the object to which it is attached.

4. ____ Gravitational forces exist between any two masses and can usually be neglected unless one of those masses is very large. The gravitational force that a car exerts on a caravan is negligible; the electromagnetic force of contact that the car exerts on the caravan is the force that pulls the caravan along. In practice, the only gravitational force that usually concerns us is the gravitational attraction of the Earth. One of the results of the work of Newton is the introduction of the concept of gravity. Gravity is a very mysterious force. How one mass exerts force on another when there is no contact between them and nothing in the space between them is the mystery. As gravity is such a familiar force, its strangeness is often overlooked.

 

VOCABULARY STUDY

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