| 1. | For the same rating which of the following motors has the highest starting torque ? | |
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Synchronous motor
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Universal motor
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Split-phase motor
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All have identical starting torque
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Report Question| 2. | Which of the following statements regarding permanent-split single value capacitor motor is incorrect ? | |
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It is generally used for exhaust and intake fans and unit beaters
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It is easily reversed because of its low running torque
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It has very low power factor at full load
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It is more sensitive to voltage variations because of its low running torque
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| 3. | What could be the size of a universal motor for use in vacuum cleaners ? | |
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2 H.P.
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1 H.P.
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3/4 H.P.
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1/4 H.P.
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| 4. | In a universal motor, the most common cause of brush sparking is ? | |
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open armature winding
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shorted armature winding
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shorted field winding
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all of the above
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| 5. | centrifugal switch disconnects the auxiliary winding of the motor at about ...... percent of synchronous speed ? | |
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30 to 40
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70 to 80
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80 to 90
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100
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| 6. | The wattage rating for a ceiling fan motor will be in the range ? | |
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200 to 250 W
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250 to 500 W
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50 to 150 W
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10 to 20 W
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| 7. | A schrage motor can run on ? | |
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zero slip
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negative slip
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positive slip
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all of the above
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| 8. | Direction of rotation of a split phase motor can be reversed by reversing the connection of ? | |
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running winding only
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starting winding only
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either (a) or (b)
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both (a) and (b)
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| 9. | A centrifugal switch is used to disconnect starting winding when motor has ? | |
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run for about 1 minute
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run for about 5 minutes
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Picked up about 50 to 70 per cent of rated speed
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picked up about 10 to 25 per cent of rated, speed
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| 10. | If the capacitor of a single-phase motor is short-circuited ? | |
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the motor will not start
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the motor will run
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the motor will run in reverse direction
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the motor will run in the same direction at reduced r.p.m.
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