| 1. | Which of the following motors has two separate windings on the motor ? | |
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Repulsion motor
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Repulsion induction motor
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Repulsion start induction run motor
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None of the above
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Report Question| 2. | In a A.C. series motor armature coils are usually connected to commutator ? | |
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through resistance
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through reactance
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through capacitors
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solidly
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| 3. | If a D.C. series motor is operated on A.C. supply, it will ? | |
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spark excessively
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have poor efficiency
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have poor power factor
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all of the above
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| 4. | Locked rotor current of a shaded pole motor is ? | |
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equal to full load current
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less than full load current
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slightly more than full load current
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several times the full load current
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| 5. | Which of the following statements regarding hysteresis motor is in incorrect ? | |
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It is extremely sensitive to fluctuations in supply voltage
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Its high starting torque is due to its high rotor hysteresis loss
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It is extremely quiet in operation
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It accelerates from rest to full-speed almost instantaneously
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| 6. | Which of the following motors is used in a situation where load increases with speed ? | |
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Induction motor
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3 phase series motor
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Schrage motor
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Hysteresis motor
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| 7. | Which of the following applications would need the smallest size of motor ? | |
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Table fan
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Sewing machine
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Domestic mixi
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Electric clock
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| 8. | Shading coils, in case of a shaded pole motor, are used to ? | |
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protect against sparking
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reduce windage losses
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reduce friction losses
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Produce rotating magnetic field
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| 9. | The direction of rotation of universal motor can be reversed by ? | |
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interchanging the brush leads
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switching over from A.C to D.C
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reversing the supply terminals
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any of the above
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| 10. | When a universal motor is operated on no-load, its speed is limited by ? | |
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supply voltage frequency
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armature-reaction
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windage and friction
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weight of the armature
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