Методическая разработка по предмету «Английский язык» по теме : «фос по специальностям спо «Технология машиностроения»

часть)

Modern DC generators use drum armatures that usually consist of a large number of windings set in longitudinal slits in the armature core and connected to appropriate segments of a multiple commutator. In an armature having only one loop of wire, the current produced will rise and fall depending on the part of the magnetic field through which the loop is moving. A commutator of many segments used with a drum armature always connects the external circuit to one loop of wire moving through the high-intensity area of the field, and as a result the current delivered by the armature windings is virtually constant. Fields of modern generators are usually equipped with four or more electromagnetic poles to increase the size and strength of the magnetic field. Sometimes smaller interpoles are added to compensate for distortions in the magnetic flux of the field caused by the magnetic effect of the armature.

DC generators are commonly classified according to the method used to provide field current for energizing the field magnets. A series-wound generator has its field in series with the armature, and a shunt-wound generator has the field connected in parallel with the armature. Compound-wound generators have part of their fields in series and part in parallel. Both shunt-wound and compound-wound generators have the advantage of delivering comparatively constant voltage under varying electrical loads. The series-wound generator is used principally to supply a constant current at variable voltage. A magneto is a small DC generator with a permanent-magnet field.
2.ТЕСТЫ.

TEST 1. PAST SIMPLE / PAST CONTINUOUS / PAST PERFECT CONTINUOUS /

PAST PERFECT

4. 
   I (talk) over the phone when they brought me the letter.
   

A talked B had talked С had been talking D was talking

5. 
   They (sit) in the room when the taxi arrived.
   

A sat В had sat С had been sitting D were sitting

6. 
   He quickly forgo: everything he (learn) at school.
   

A learnt В had learnt

С had been learning D was learning

4.I visited Brazil in April. I (stay) at a nice hotel for a fortnight

A stayed В had stayed С had been staying D was staying

5. I(stay) at the hotel for a fortnight when I received your letter.

A stayed В had stayed С had been staying D was staying
6.The musician (play) the piano for a whole hour when we came in.

A played В had played С had been playing D was playing

7. Alice closed the magazine and rose from the sofa on which f she (lie) for more than two hours. A lay В had lain С had been lying D was lying

8. A man (be) unconscious for a few minutes when an ambulance arrived.

A was В had been С had being

9. We (walk) along a forest road for two hours when we saw a house.

A walked В had walked С had been walking D were walking

10.I (talk) over the phone for a whole hour when the porter knocked at the door.

A talked В had talked С had been talking D was talking
TEST 2. PLURAL (make plural form)

2. 
   a baby 2. a pencil
   

A babys A penciles

B babies B pencils

3. 
   a man 4. an umbrellas
   

A man A umbrellaes

B men C mans B umbrellas C umbrells

5. a boy 6. a city

A boys A citys

B boies C boyes B cities C cityes

7. a mouse 8. A postman

A mouses A postman

B mice C mouss B postman C postman

9. a knife 10. a fish

A knifes A fish

B knifs C knives B fishes C fishs