Work in pairs or groups. Read the following definitions and decide what they mean. Then enlarge the list of definitions and ask your groupmates to guess what they mean

1. the number of atoms likely to decay in a given infinitesimal time interval (dN/dt) is proportional to the number (N) of atoms present.

2. any material capable of attracting iron and producing a magnetic field outside itself.

3. radiation that produces ions in matter during interaction with atoms in the matter.

4. electromagnetic radiation that can be detected by the human eye.

5. emission of light from a substance exposed to radiation and persisting as an afterglow after the exciting radiation has been removed.

6.spontaneous loss of water by a hydrated salt, which occurs when the aqueous tension of the hydrate is greater than the partial pressure of the water vapour in the air.

7. a set of numbers arranged in rows and columns so as to form a rectangular array.

8. is the property of certain nuclides of spontaneously emitting particles or gamma radiation.

9. ………………………………………………………………………………

10. …………………………………………………………………………….

11. …………………………………………………………………………….

12. …………………………………………………………………………….

Explain the meanings of the words below.

1. indivisible

2. immutable

3. inert

4. external

5. powerful

6. magnetic

7. similar

8. contradictory

1.5. Pay attention to the Complex Object after the verbs: to allow, to permit, to enable, to let, to make, to cause.

1. This model enables us to estimate how thick dense plasma must be to absorb all the incident laser light.

2. Spectroscopic studies of the radiation have enabled determination of the temperature to be made.

3. Other scanning methods will enable the over-all optical gain to be accomplished which is equal to the refractive index, n, of the optical material employed.

4. Classical physics doesn't allow physicists to describe phenomena on the atomic or molecular level, it is appropriate to seek a quantum-mechanical description of such phenomena.

5. Dependence of the phase relation between cavity field and the signal does not permit the signal to be amplified or attenuated.

6. These effects let the viewer infer a three-dimensional structure from a two-dimensional micrograph.

7. Some modern computers let eight programmes run simultaneously if all the necessary equipment is available.

8. In an ordinary TV set an electron beam causes the luminous image to appear on the tube.

9. There is no way to make a black hole rotate any faster than a=l; in effect a hole with a rotation parameter very close to 1 should slow down.

10. If there were no earth's gravitation the satellites would move through airless space in a straight line at a uniform speed.

11. Constant temperature must be maintained to make the process continue at any rate.

12. The pressure in the cylinder makes the piston descend; the piston is made to descend as the pressure in the cylinder rises.

13. And eventually more sensitive instruments made it possible to detect X-rays from distant sources at very high energies, corresponding to wavelength of Angstroms or less.

14. Indeed, new results make it necessary to modify the picture that has emerged from earlier experiments.

1.6. Mind the translation of the verb "to prove".

Example: We proved this metal to be an alloy.

Мы доказали, что этот металл является сплавом.

The metal proved to be an alloy.

Оказалось, что этот металл является сплавом.

The metal was proved to be an alloy.

Было доказано, что этот металл является сплавом.

1. Former tests proved these figures to be equally important.

These figures proved to be equally important.

These figures were proved to be equally important.

2. We proved the two reports to be contradictory.