| 1. | Under average service conditions, motor bearings may be safely operated at temperatures upto ? | |
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120ºC
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105ºC
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95°C
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75ºC
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View Answer
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Report Question| 2. | For a 50 H.P. motor, which type of rotor will be preferred ? | |
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Die cast aluminium rotor
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Wound rotor
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Squirrel cage rotor using round copper bars
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Squirrel cage rotor using rectangular copper bars
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| 3. | Type of bearing used for 25 H.P. motor ? | |
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roller bearing
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bush bearing
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needle bearing
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ball bearing
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| 4. | If air gap of the induction motor is increased, its ? | |
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power factor will decrease
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magnetising current will decrease
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magnetising current will increase
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power factor will increase
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| 5. | The starting torque of a three phase induction motor can be increased by ? | |
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increasing slip
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increasing current
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both (a) and (b)
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none of the above
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| 6. | A squirrel cage induction motor is not selected when ? | |
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initial cost is the main consideration
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maintenance cost is to be kept low
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higher starting torque is the main consideration
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all above considerations are involved
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| 7. | For driving high inertia loads best type of induction motor suggested is ? | |
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slip ring type
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squirrel cage type
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any of the above
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none of the above
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| 8. | The overheating of an induction motor maybe due to ? | |
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overloading
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loss of ventilation
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low supply voltage
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any of the above
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| 9. | The rotor of an induction motor runs at ? | |
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synchronous speed
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below synchronous speed
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above synchronous speed
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any of the above
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| 10. | Star-delta starting of motors is not possible in case of ? | |
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single phase motors
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variable speed motors
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low horse power motors
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high speed motors
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