1. The rotating part of a single - phase motor is called

Rotor

Stator

Running winding

Starting winding

2. If supply voltage in the above case is 110v, the voltage rating of the capacitor should be _ volt

2750

550

22

220

3. A 4 - pole induction motor is fed from a 50 hz source and is running at a slip of 4%. The speed of the motor is _ rpm

1500

1440

1560

1620

4. Out of the following methods of starting a 3-phase induction motor, which one requires six stator terminals?

Star- delta

Rotor rheostar

Autotransformer

Direct - on - line

5. Under no- load conditions power factor of an induction motor is about

0.2 lag

0.9 lag

Unity

0.5 lead

6. If maximum torque of an induction motor is 200 kg-m at a slip of 12%, the torque at 6% slip would be _ kg-m

100

160

50

40

7. If full load speed of a 6-pole, 50 hz SCTM is 960 rpm, it’s speed at half - load is _ rpm

480

980

940

990

8. When line voltage of an induction motor is reduced to 75% of its rated value, it’s starting current is reduced by _ percent

25

75

56.25

177.7

9. The magnetising current drawn by transformers and induction motors is the cause of their _ power factor

Zero

Unity

Lagging

Leading

10. The no-load speed of a 3- phase, 4- pole induction motor connected to a 3-phase, 50-hz supply is expected to be _ rpm

1400

1480

1450

1498