1. . . .
Vocabulary
to detect ,
to employ ,
to extend , ()
to guide ,
to rotate (), ()
to scan ,
to feed (fed) -
detector tube -
extended aerial -
guide channel -
unguided missile -
feed circuit -
SPHERES OF USE OF THE RADARS
Radar is classified as means belonging to the sphere of radio communication. The word RADAR is an abbreviation of the words Radio Detection And Ranging.
Radar as a term is now used to include any system employing microwaves. To them belong microwaves ranging from 30 cm to 1 mm. Radar as a system of communication is used for locating, identifying, or guiding such moving objects as ships, aircraft, missiles, or artificial satellites. The radar system consists essentially of a generator, of electromagnetic radiation, the output of which is pulse modulated. Modulation is known as the process of varying some characteristic of one wave usually it is a radio-frequency carrier wave in accordance with some characteristic of another wave.
Then the output is fed to a movable aerial where from it is radiated as a beam. The aerial is rotating continuously when in use.
Questions
1. What is the basic principle of radar?
2. What is radar as a system of communication used for?
3. What function does a movable aerial perform?
4. What device was the radar technique extended to?
5. How is modulation defined?
6. What is the meaning of the abbreviation "radar"?
7. What kind of waves does radar employ?
Task 2. Translate and write down the following words and word combinations in your workbooks. Make up a short plan of the text SPHERES OF USE OF THE RADARS and write it down in your workbooks, summarize the text in short.
2. . » , .
Short theoretical information and a sample of implementation
( )
Past Simple Past Continuous
, . , , . , , .
| Past Simple | Past Continuous | |
| (Affirmative Form) | S (Subject) + V-ed ( ) | S + was/were + V-ing |
| I/You/He/She/We/They installed the equipment yesterday. | I/He/She was installing the equipment. | |
| I/You/He/She/We/They went to college last Monday. | You/We/ They were going to college. | |
| (Negative Form) | S (Subject) + did not + V ( to) | S + was/were + not + V-ing |
| I/You/He/She/We/They didnt install the equipment last evening. | I/You/He/She/We/They wasnt/werent going to college. | |
| (Interrogative Form) | + did + S + V ( to) | + was/were + S + V-ing |
| Did + S + V ( to) | Was/were +S + V-ing | |
| Why did they installed the equipment yesterday? | Why were they installing the equipment? | |
| Did they go to college last Sunday? | Was he telling you the truth? |
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