UNIT-VIII:
Single phase induction motors
1. At starting, the line current of a capacitor start
induction motor is ______ the normal full load current[ b ]
(a)8 to 10 times (b)4 to 5
times (c) equal to (d)7 to 8 times
2. The main winding and starting winding of a
single phase induction motor are connected in__________ across the supply. [b ]
(a)series (b) parallel
(c)series parallel (d)none
3. In
capacitor start induction motor the angle between Im and Is is about 75˚
4. The
purpose of starting winding in a single phase induction motor is to produce rotating flux
5. A
single phase induction motor employs squirrel cage
rotor
6. The main winding and starting winding of a
single-phase induction motor are connected in ________ across the supply [b ]
(a) series (b) parallel (c)
series-parallel (d) none of the above
7. A two-phase a.c. servometer has [b ]
(a) wound rotor (b) cage
rotor (c) wound or cage rotor (d) a rotor similar to that in d.c motors
8. A
50 Hz, 4-pole, single-phase induction motor will have a synchronous speed of 1500 RPM
9. The
full-load efficiency of a shaded-pole motor is about 30 to 35 %.
10. The
amount of torque required to move a stepper motor one full step is called holding torque
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