Read the text. Match names and symbols of units with their definitions.

    As the nineteenth century drew to a close, scientists could reflect with satisfaction that they had pinned down most of the mysteries of the physical world: electricity, magnetism, gases, optics, acoustics, kinetics, and statistical mechanics, to name just a few, all had fallen into order before them. They had discovered the X- ray, the cathode ray, the electron, and radioactivity, invented the ohm, the watt, the Kelvin, the joule, the amp, and the little erg.

    If a thing could be oscillated, accelerated, perturbed, distilled, combined, weighed, or made gaseous scientists had done it, and in the process produced a body of universal laws so weighty and majestic that we still tend to write them out in capitals: the Electromagnetic Field Theory of Light, Richter’s Law of Reciprocal Proportions, Charles’s Law of Gases, the Law of Combining Volumes, the Zeroth Law, the Valence Concept, the Laws of Mass Actions, and others beyond counting. The whole world clanged and chuffed with the machinery and instruments that their ingenuity had produced. Many wise people believed that there was nothing much left for science to do.

Units named after scientists

1. Ampere (A)            a) a unit of force

2. Becquerel (Bq)  b) a unit of pressure, stress

3. Coulobm (C)     c) a unit of frequency

4. Farad (F)           d ) unit of energy, work, quantity of heat

5. Joul (J)              e) a unit of electric capacitance

6. Herzt (Hz)         f) a unit of electric charge, quantity of electricity

7. Kelvin (K)         g) unit of power

8. Newton (N)       h) a unit of electrical current

9. Pascal (Pa)        i) a unit of activity of a radionuclide

10. Watt (W)         j) unit of thermodynamic temperature

 

7. Read the text and decide whether the following statements are true or false:

С onstants

1. The constants depend on the accurate measurements.

2. Physicists have been fascinated by the nature of constants.

3. There have been considerable insights of the nature of constants lately.

4. Modern scientists come up with plausible explanation of constants.

 

    Some things never change. Physicists call them constants of nature. Such quantities as the velocity of light c, Newton’s constant of gravitation, G, and the mass of the electron, m (e) are assumed to be the same at all places and times at the universe. They form the scaffolding around which the theories of physics are erected, and they define the fabric of our universe. Physics has progressed by making ever more accurate measurements of their values.

And yet, remarkably, no one has ever successfully predicted or explained any of the constants. Physicists have no idea why they take into account the special numerical values that they do. The only thread running through the values is that if many of them were even slightly different, complex atomic structures such as living beings would not be possible. The desire to explain the constants has been one of the driving forces behind the effort to develop a complete unified description of nature, or “theory of everything”. Physicists have hoped that such a theory would show that each of the constants of nature could have only one logically possible value. It would reveal an underlying order to the seeming arbitrariness of nature.

In recent years the status of constants has grown more muddled, not less. Researchers have found that the best candidates for a theory of everything, the variant of string theory called m-theory, is self-consistent only if the universe has more than four dimensions of space and time – as many as seven more. One implication is that the constants we observe may not, in fact, be the truly fundamental ones. Those live in the full higher-dimensional space, and we see only their three-dimensional “shadows”.

Meanwhile physicists have also come to appreciate that the values of many of the constants may be the result of mere happenstance, acquired during random events and elementary particle process early in the history of the universe.

No further explanation would be possible for many of our numerical constants other than they constitute a rare combination that permits consciousness to evolve. Our observable universe could be one of many isolated oases surrounded by an infinity of lifeless space – a surreal place where different forces of nature hold sway and particles such as electrons or structures such as carbon atoms could be impossibilities. If you tried to venture into that outside world, you would cease to be.

Thus, string theory gives with one hand and takes with the left. It was devised in part to explain the seemingly arbitrary values of the physical constants, and the basic equations of theory contain few arbitrary parameters. Yet so far string theory offers no explanation for the observed values of the constants.

 

VOCABULARY STUDY

8. Form the word from the given one in each line:

Physical С onstants

Constant is a mathematical quantity that is not__ (1).                       vary

Constants occur in almost all polynomials in the form of__ (2)      efficient

or addends. Constant addends are __(3) by c, C, k or K.                symbol

Some constants occur __ (4). One such constant is                          nature

Pi , which is of__ (5) importance in mensuration                            consider

(a branch of geometry dealing with measurement of __(6),              long

area and volume), another is e (__ (7) or Euler’s number,                exponent

the base of natural algorithms). Physical quantities whose___(8)     scale

magnitude is constant, such as c, the velocity of light (the__(9)   electromagnet

constant) or G, the universal __(10) constant,                                   gravity

are termed physical constants.

 

GRAMMAR PRACTICE: Modals + Infinitives (GR-13 p.203)

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