| 1. | For which of the applications a reluctance motor is preferred ? | |
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Electric shavers
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Refrigerators
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Signalling and timing devices
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Lifts and hoists
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Report Question| 2. | The electric motor used in portable drills is ? | |
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capacitor run motor
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hysteresis motor
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universal motor
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repulsion motor
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| 3. | After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on ? | |
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running winding
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rotor winding
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field winding
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compensating winding
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| 4. | In a shaded pole motor, the direction of rotation is from ? | |
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shaded pole to main pole
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main pole to shaded pole
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depends on supply line polarity
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none of the above
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| 5. | Which of the following motors is used for unity power factor ? | |
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Hysteresis motor
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Schrage motor
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Universal motor
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Reluctance motor
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| 6. | Starting winding of a single phase motor of a refrigerator is disconnected from the circuit by means of a ? | |
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magnetic relay
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thermal relay
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centrifugal switch
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none of the above
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| 7. | When a ceiling fan employing a capacitor run motor is switched on, it hums but does not burn. When it is driven by external means, it runs in whatever direction it is made to run. The trouble is due to ? | |
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blown fuse
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short in the capacitor
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an open in centrifugal switch
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an open in capacitor
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| 8. | A.C. series motor as compared to D.C. series motor has ? | |
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smaller brush width
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less number of field turns
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more number of armature turns
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all of the above
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| 9. | Which of the following is most economical method of starting a single-phase induction motor ? | |
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Inductance-start method
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Split-phase method
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Resistance-start method
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Capacitance-start method
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| 10. | Which motor will make least noise ? | |
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Hysteresis motor
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Capacitor motor
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Shaded-pole motor
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Universal motor
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