My speciality. Овчинникова Т.Е - 33 стр.

      2.10.8 Answer the questions

1.What happens if an electron strikes the plate with sufficient velocity ? 2. What
process is called secondary emission ? 3. In what case will secondary electrons be
attracted to the screen ? 4. What does the amount of secondary emission under given
conditions of electron bombardment depend on ? 5. What would cause to remember
in computing the reactance?

       2.10.9 Find a conditional sentence and define its type, tense form
(paragraph 2), gerunds (paragraphs 4, 5). Find the function of would (paragraph
4), should (paragraph 5). Find infinitive in the function of attribute and define
its form.

      2.10.10 Underline suffixes and prefixes. Translate the words into Russian

depend, dependence, independence, independent, independently, use (n), useful,
usefulness, usefully; careful, carefully, carefulness; useless, uselessness, uselessly;
careless, carelessly, carelessness.

      2.10.11 Describe figures 11 and 12

      2.10.12 Summarize the main points the text

                               BEAM POWER TUBES

1. Instead of using a suppressor grid to control the secondary emission from the plate,
it is possible to obtain the same effect by shaping the tube elements in such a way as
to control the space charge near the place. The beam – forming plate is connected to
the cathode, and its potential is therefore zero. The field produced           by this
combination of elements is such as to cause a concentration of electrons to occur near
the plate, and thereby to produce a region of minimum potential there. As long as the
plate potential is higher than the potential minimum due to electron concentra-
tion, secondary electrons will return to the plate, just as if a suppressor grid were
present.
2. The accurate focusing of the electron beam causes it to pass between the turns of
the screen grid. When this is done the screen current is much reduced as compared
with earlier tubes, and most output power is available for a given amount of peak
cathode emission.

      2.10.13 Answer the questions

1. How is it possible to obtain the same effect instead of using a suppressor grid? 2.
What is the beam – forming plate connected to?