4. For a long time the atom was thought to be indivisible. 5. There is a tendency for these tiny (small) currents to cancel one another out.
6. It will hardly be possible for them to solve this problem. 7. It will be easy for the trained technician to locate the fault. 8. They waited for the experiment to be continued. 9. Automatic control permits this process to be sped up.
In the blanks below insert the proper form of verbs given in Russian in brackets. The text concerns the theory of electron tube.
1. The part of some devices ... in electronic control . . . the electron tube (используемых, является).
2. Like those ... in radios, it ... of a glass or metal envelope that . . . several electrodes (используемым, состоит, включает).
3. The simplest tube . . . the diode, which ... of two electrodes, an anode or plate, and a cathode (есть, состоит).
4. For this tube . . . , it ... necessary that electrons . . . (работала, есть, эмиссировались).
5. This . . . so . . . that it . . . a course of electrons when it . . . (сконструирован, может стать, нагревают).
6..........the electrons (нагревание стремится освободить).
7. Some cathodes . . . like the filament of an incandescent lamp with an . . . coating of a material, which ... a large number of electrons while the filament ... hot (делают, дополнительный высвобождает, есть).
8. The tube......after the . . . material . . . by long use (прекратит
действовать, покрывающий, испарится).
9. Some tubes ... a cathode that ... indirectly (имеют, нагревают).
10. ... useful, the electrons that . . . from the cathode . . . , otherwise they . . . simply . . . around in space or . . . cathode (чтобы быть полезными, испускаются, должны быть собраны, будут разноситься, вернутся).
11. The electrons ... by the anode when it ... a positive charge on it (будут собираться, имеет).
12. The anode ... to the positive terminal of a battery . . . the electrons . . . quickly to the anode and ... a current . . . through the empty space between the anode and cathode (подключается, заставляя, двигаться, заставлять, протекать).
18 15
Ноте exercise. Write a letter to a firm requesting delivery of an electric equipment set. Don’t forget to include all the information concerned. Note that you expect delivery at the specified dates and on usual terms.
19 20
Home exercise. Rephrase the indirect instructions from the text below in a direct way where it is possible.
Model. The megger reading may be well within the prescribed parameters for the motor to be started. — Follow the prescribed parameters of the megger readings while starting the motor.