4. It is too early to properly weigh the significance of this method.

5. It has long been established that portions of the Earths upper atmosphere are ionized enough to cause refraction and reflection of radio waves.

6. The negative poles in this case are far enough away so as not to influence the positive poles.

7. A winged spacecraft has rather large areas to be heat-protected.

8. These regions were too far away to be affected by the explosion.

9. Mere * observations of the stars cannot tell us which are young and which are old, for all their changes are far too slow to detect.

10. Переведите предложения, определив инфинитивные конструкции и функции инфинитивов.

1. Advancement in electronic techniques appears to be endless.

2. All forms of radiant energy have been found to travel through space with the same speed.

3. Temperatures on the surface of Mars, which seems to be the most comfortable place for life to exist beyond our Earth within the solar system, are also of some interest.

4. Most physicists believed in the latter half of the nineteenth century cathode rays to be charged particles.

5. Satellites in Earth orbits of about 600 miles or greater can normally be expected to remain in orbit for thousands of years.

6. The first satellite to be designed and developed in England was Ariel 3 which was successfully put into orbit on May 5, 1967.

7. To say that an object is travelling at a speed of 20 ft/sec (feet per second) does not describe the motion completely.

8. A day on Jupiter has been observed to be 9 Earth hours-and 55 minutes long, the shortest of any of the planets.

9. When sound waves are directed on the diaphragm they cause it to move backwards and forwards.

10. The choice of radioisotope to be used as the source is determined by the thickness of the product to be measured.

11. The penetrating power of this new radiation was an obvious point to investigate.

12. A current which always flows in one direction along a wire is said to be a direct current.

13. Fouriers theory states that any waveform that repeats at regular time intervals can be shown mathematically to be equivalent to the sum of a series of sine waves of different amplitudes and frequencies.

* mere -простой

14. The first attempt to measure the speed of propagation of light was undertalcen by Galileo in a very primitive way.

15. As we have seen earlier in this chapter, to cause thermonuclear reactions extremely high temperatures are required.

16. From classical electrodynamics we know that when a charge is accelerated it radiates. (This is the process that causes radio and television antennae to radiate).

17. In the so-called "gas counters" the radiation to be detected causes ionization in the gas, and the free charge is then collected and measured.

18. A satellite launched into an orbit which approaches the Earths surface closer than 200 km will not circulate for long. The air drag is sufficient to cause the orbit to spiral in quite quickly to the dense lower atmosphere.

19. These rays were shown by J. J. Thomson and others to consist of a mixture of molecules and atoms of the residual • gas,

20. For a sound to be heard by the human ear it should be between the frequencies Ы approximately 20 cycles and 15,000 cycles.

21. Newton stated that the force which makes objects fall towards the Earth is only a special case of a general attraction between any two masses.

22. The birthplace of man Is believed to-be somewhere in the eastern, hemisphere but in just what regiort" or even on what continent it is still impossible to say.

23. Interference by cosmic ray particles makes it necessary for neutrino detection to be carried out deepunderground where other particles cannot penetrate.

24. In the course of his theoretical investigations Maxwell discovered the pressure of light. He derived this effect from the electromagnetic theory, but as a matter of fact it can be shown to follow from any wave theory.

25. Even though the demand for coal and lignite * continues to rise there does not appear to be any danger of running out of these fuels for several hundred years at least.

26. The first rocket to be used as a vehicle for scientific research was the rocket-powered gyro-controlled missile.

27. This property of matter to resist any change in its motion is called inertia.

28. Calculations concerning the interior properties of the Sun show it to contain mostly hydrogen and helium.

29. The unstable isotopes that are almost stable have been found to occur naturally and these were known as early as the turn of the century.

• residual - остаточный

• lignite - бурый уголь

2 Зак. 849 33

30. For the purpose of this boolc we shall assume nuclei to be made up of two types of constituents, neutrons and protons.

31. There are certain principles to be followed in the design of propellers.

32. The important thing to notice is that the resolving power * depends on the diameter of the object glass.

33. In the electromagnetic theory of radiation the atom is supposed to be similar to the antenna of a radio transmitter, although much smaller and radiating a much higher frequency.

34. To determine the magnitude of anything, it is necessary to make a measurement.

35. For the sound to arise it is necessary to have a sound source and a medium to travel through.

36. If plane waves fall perpendicularly on a surface they may be shown to exert a pressure on it of a magnitude equal to the density of energy in the waves. This result is exceedingly difficult to observe, as the pressure is very small in practical cases.

37. In 1850 the French physicist Jean Foucault measured the speed of light in water. He found it to be substantially less than the velocity in air.

38. The basic requirements for any orbital research laboratory are heavily dependent upon the experiments to be performed.

39. There appear to be small but real fluctuations of a few per cent in the solar constant.

40. The penetrating power of this new radiation was an obvious point to investigate.

41. At first, man believed the Earth to be flat.

42. Considerable progress has been made with the difficult task of processing the information quickly enough for it to be of use for weather forecasting.

43. On the basis of new theoretical investigations it was demonstrated that it is hardly possible for the primary cosmic radiation to be of "near-solar" or metagalactic origin.

44. The hydrogen atom was the object of the first theoretical attack, because as the lightest of all atoms it was assumed to have the simplest structure.

45. In order for life to arise on a planet, the mass of the planet must lie between certain limits.

46. There does not appear to be a promising * approach to the solution of the problem.

47. As mentioned earlier, there seems to be no doubt that the X-ray emission changes very much over the solar cycle.

48. Using data of this kind it was found that the theory does not seem to give results which are in good agreement with observation.

♦ resolving power - разрешающая способность

* promising -перспективный

be in agreement - соответствовать