| 1. | The number of slip rings on a squirrel cage induction motor is ? | |
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four
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three
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two
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none
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Report Question| 2. | The value of average flux density in air gap in an induction motet, should be small ? | |
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to achieve good efficiency
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to get poor power factor
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to get good power factor
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for minimum cost
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| 3. | Which of the following motors requires the most complicated speed control arrangement ? | |
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DC shunt motor
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Rotor supplied three-phase commutator
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Stator supplied three-phase commutator
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Three-phase squirrel-cage induction motor
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| 4. | Which of the following methods of speed control is not affected through stator side ? | |
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Change of number of poles
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Change of rotor resistance
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Change of supply voltage frequency
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Change of supply voltage
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| 5. | Which of the following motors has the highest power to weight ratio ? | |
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Synchronous motor
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Capacitor motor
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Induction motor
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Universal motor
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| 6. | When a load on a squirrel-cage induction motor is increased from no-load to full load, which of the following statement is incorrect ? | |
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Slip increases
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The magnetising component of the stator exiting current is increased
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Stator power factor is improved
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Torque developed by the motor increases till it equals the applied torque
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| 7. | In induction motor, percentage slip depends on ? | |
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supply frequency
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supply voltage
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copper losses in motor
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none of the above
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| 8. | The speed characteristics of an induction motor close]y resemble the speed load characteristics of which of the following machines ? | |
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D.C series motor
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D.C. shunt motor
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universal motor
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none of the above
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| 9. | If an induction motor with certain 'ratio of rotor to stator slots, runs at ~ of the normal speed, the phenomenon will be termed as ? | |
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humming
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hunting
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crawling
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cogging
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| 10. | For which motor the speed can be controlled from rotor side ? | |
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Squirrel-cage induction motor
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Slip-ring induction motor
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Both (a) and (b)
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None of the above
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