| 1. | The complete circle diagram of induction motor can be drawn with the help of data found from ? | |
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no-load test
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blocked rotor test
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stator resistance test
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all of the above
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Report Question| 2. | The circle diagram for an induction motor cannot be used to determine ? | |
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efficiency
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power factor
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frequency
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output
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| 3. | Temperature of the stator winding of a three-phase induction motor is obtained by ? | |
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resistance rise method
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thermometer method
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embedded temperature method
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all above methods
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| 4. | The torque of an induction motor is ? | |
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directly proportional to slip
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inversely proportional to slip
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proportional to the square of the slip
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none of the above
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| 5. | If there is an open circuit in the rotor of a squirrel cage induction motor ? | |
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rotor will overheat
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line fuses will blow
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motor will be noisy
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motor will not start
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| 6. | The pull-out torque for a normal squirrel cage induction motor usually occurs at a percentage slip of about ? | |
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10 to 16 per cent
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20 to 25 per cent
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35 to 46 per cent
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50 to 60 per cent
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| 7. | ln case of a 3-phase wound rotor induction motor an increase in rotor resistance affects the motor performance in the following way ? | |
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the motor efficiency decreases
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the motor efficiency increases
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starting current decreases
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starting current increases
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| 8. | The difference between the synchronous speed and the actual speed of an induction motor is known as ? | |
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lag
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regulation
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slip
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back lash
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| 9. | A wound rotor induction motor can be distinguished from squirrel cage induction motor by ? | |
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diameter of shaft
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size of frame
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presence of slip ring
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direction or rotation
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| 10. | Which of the following type of bearing is generally used to support the rotor of an induction motor ? | |
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Ball bearing
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Needle bearing
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Plummer block
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Bush bearing
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