d mainly for portable power sources.
Electric power produced in large power stations generally is transmitted by using an that reverses direction 25, 50, 60 times per second.
The basic unit for measuring electric power is the - .
Watt, alternating current, electricity, electric power, power stations.
Task 4. Read the words and put down their Russian equivalents. (Переведите с английского на русский язык)
Generator
Material
Mechanical
Thermal
Motor
Relay
Contact
System
Automatic
Commutator
Stator
Rotor
Process
Rheostat
Task 5. Fill in using the verbs to detect, to appear, to disappear, to decrease. (Вставьтеподходящийпосмыслуглагол в нужнойформе. )
When resistance increases, the risk of electric shock . . . . .
Faults in electric installations are . . . . by means of special devices.
Electric power . . . . only on live conductors with power on.
When the device is switched off electric power . . . . .
Task 6. Choose the suitable words. (Выберите подходящее слово из скобок. )
The danger ofelectric shock (appears, disappears) when the conductor becomes (live, dead).
Current passes through faulty (earthed, unearthed) part of installations when the power is on.
Low accuracy of measurement is (an advantage, a disadvantage) of the measuring device.
The danger ofelectric shock (increases, decreases) in the wet and hot atmosphere.
No current flows through a (dead, live) conductor.
Task 7. Complete the sentences choosing the right ending. (Закончите предложения, подобрав соответствующее продолжение. )
Resistors are used . . . a) to convert different forms of energy into
mechanical energy
An electric cell is u
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