01. In a split phase motor, the running winding should have
High resistance and low inductance
High resistance and High inductance
Low resistance and high inductance
Low resistance and Low inductance
02. If the capacitor of a single-phase motor is short-circuited
The motor will not start
The motor will run in the same direction at reduced speed
The motor will run in reverse direction
None of the above
03. In a split phase motor
Both starting and running windings are connected through a centrifugal switch
Centrifugal switch is used to control supply voltage
The running winding is connected through a centrifugal switch
The starting winding is connected through a centrifugal switch
04. The torque developed by a single-phase motor at starting is
less than the rated torque
More than the rated torque
zero
None of the above
05. In a capacitor start and run motors the function of the running capacitor in series with the auxiliary winding is to
1 point
Improve power factor
Reduce fluctuations in torque
Increase overload capacity
To improve torque
06. Which of the following motor will have relatively higher power factor?
1 point
Capacitor start motor
Shaded pole motor
Capacitor run motor
Split phase motor
07. A centrifugal switch is used to disconnect ‘starting winding when motor has
1 point
Picked up 10% speed
Picked up 20% speed
Picked up 5 – 10% speed
Picked up 50 – 70% speed
08. In repulsion motor direction of rotation of motor
1 point
Same as that of brush shift
Independent of brush shift
Opposite to that of brush shift
None of the above
09. If a particular application needs high-speed and high starting torque, then which of the following motor will be preferred?
1 point
Shaded pole motor
Capacitor start motor
Capacitor run motor
Universal Motor
10. Which of the following motor is used in the mixer?
1 point
Repulsion Motor
Reluctance Motor
Hysteresis Motor
Universal Motor
11. The direction of rotation of an hysteresis motor is determined by
1 point
Retentivity of the rotor material
Position of shaded Pole with respect to the main pole
Interchanging the supply leads
None of the above
12. Direction of rotation of a split phase motor can be reversed by reversing the connection of
Starting winding
Running winding
Either 1 or 2
None of the above
13. In a capacitor start single-phase motor when capacitor is replaced by a resistance
Motor will consume less power
Motor will continue to run in the same direction
Motor will stop
None of the above
14. A capacitor start single phase induction motor when capacitor is replaced by inductance
Motor will not start
Start and run
Small hp motor can start but large hp motor will not start
None of the above
15. A hysteresis motor works on the principle of
1 point
Eddy current loss
Magnetization of rotor
Hysteresis loss
Electromagnetic induction
16. Which of the following single-phase motors is suitable for timing and control purposes
1 point
Universal Motor
Reluctance Motor
Series Motor
Split phase motor
17. In A.C. series motor compensating winding is employed to
1 point
Increase the torque
Reduce the effect of armature reaction
Reduce sparking in brushes
Both 2 and 3
18. The repulsion-start induction-run motor is used because of
Good Power factor
High efficiency
High starting torque
Low cost
19. The speed of a universal motor is generally reduced by using
Gear train
V- belt
Brakes
Chains
20. Which of the following motors can be used for unity power factor?
Hysteresis motor
Capacitor motor
Schrage motor
Split phase motor
21. In split-phase motor, auxiliary winding is made up of
Thick wire placed at top of the slot
Thin wire placed at the bottom of the slot
Thick wire placed at bottom of the slot
Thin wire placed at top of the slot
22. In a two value capacitor motor, the capacitor used for running purposes is
1 point
Paper spaced oil filled type
Air capacitor
Ceramic type
None of the above
23. In shaded pole motor, the direction of rotation of motor is
1 point
From shaded pole to the main pole
From the main pole to shaded pole
Either 1 or 2
None of the above
24. The direction of rotation of universal motor can be reversed the by reversing the flow of current through
1 point
Field winding
Armature winding
Either 1 or 2
None of the above
25. Which motor is normally free from mechanical and magnetic vibrations?
1 point
Capacitance motor
Hysteresis Motor
Reluctance Motor
Split phase motor
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