| 1. | The armature of a DC machine is made of ? | |
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mild steel
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silicon steel
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stainless steel
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cast iron
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Report Question| 2. | DC generators are designed to develop armature voltages not exceeding 650 V because of the limitations of ............ ? | |
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field winding
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armature winding
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commutator
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starters
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| 3. | A step up transformer increases ........... ? | |
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power
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voltage
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frequency
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current
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| 4. | It is economical to transmit electricity at a ? | |
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very high voltage
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very low voltage
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very high current
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None of these
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| 5. | Rotating magnetic fields are also used in 3phase induction motors rotor developing .......... ? | |
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eddy current
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voltage lag
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load current
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phase current
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| 6. | One of the speed control methods of a 3 phase induction motors is ....... ? | |
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V/F control
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stator current control
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core loss control
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eddy current control
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| 7. | A centrifugal switch is provided for disconnecting the auxiliary winding in a ............ ? | |
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Capacitor- start motor
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Capacitor run motor
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Reluctance motor
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Hysteresis motor
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| 8. | In a split phase motor, the running winding should have ? | |
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high resistance and low inductance
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low resistance and high inductance
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high resistance as well as high inductance
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low resistance as well as low inductance
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| 9. | A reluctance motor ? | |
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is self-starting
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is constant speed motor
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needs no D.C. excitation
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all options are correct
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| 10. | The speed control of a universal motor used for sewing machines is done by ? | |
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friction
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varying the resistance
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tapping the field
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centrifugal mechanism
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