Учебно-методическое пособие по чтению специальной литературы для студентов 1 курса физического факультета. Дроздова И.В - 23 стр.

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                                  Discussion
Use your background knowledge to answer the questions or to develop the points.

1. Define the following terms: chain reaction, critical mass, control rods.
2. Do we have fusion reactors? If not, why?



                                           Unit VI

                                            Laser
Pre-reading activity

         1. Do you know what the “Laser” stand for?
         2. Do you know what “coherent light” is?

Reading

I.   Read the text quickly. Match a paragraph 1-5 with a heading below:
-    Laser Types.
-    How a Laser Works.
-    Stimulated Emission.
-    Basic Principles.
-    History.

II. The following statements are false. Read the text and change one word or a phrase
in each statement to make it true.
a) A laser is a device that produces a beam of energy.
b) Information is encoded in the beam as variations in the length or shape of the light
    wave.
c) A laser is made of four basic components.
d) According to quantum mechanics, atom will interact with light of two particular
    frequencies.
e) Stimulated emission can happen only to lower-state atoms.
f) Ultraviolet laser or excimers haven’t gained widespread use in industry.
g) In 1968 Townes, Basov and Prokhorov were jointly awarded the Noble Prize for
    physics.

III. Choose the synonym. Find the underlined word in the text and translate the
sentence with it.

     1.occur, v.                             5. burst, n.
     A. repulse                              A. bulb
     B. take place                           B. explosion
     C. extend                               C. excitement