31. If a synchronous condenser is installed to current the 2400 kVA, 0.65 power factor load in a plant to unity, then kilovolt ampere rating of condenser is
    

1. 1. 27 kVA

   
   
   

   2. 1560 kVA

   
   
   

   3. 1825 kVA

   
   
   

   4. 3690 kVA

   
   
   

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   NA

   Correct Option: C

   NA

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32. If power input to the d.c. field at a 15 kVA (input) synchronous motor is 6 per cent of the rates a.c. input, then direct current that excites the field at 120 volt, is
    

1. 1. 7.5 amps

   
   
   

   2. 125 amps

   
   
   

   3. 15 amps

   
   
   

   4. none of these

   
   
   

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   NA

   Correct Option: A

   NA

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33. If a 10 pole 25 Hz alternator is directly coupled to and is driven by a 60 Hz synchronous motor, then number of poles in a synchronous motor are
    (a)

1. 1. 48
      

   
   
   

   2. 12

   
   
   

   3. 24

   
   
   

   4. none of these

   
   
   

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   NA

   Correct Option: C

   NA

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34. The torque angle at a synchronous machine operating from a constant voltage bus is usually defined as the space angle between
    

1. 1. rotor mmf wave and startor mmf wave

   
   
   

   2. rotor mmf wave and resultant flux density

   
   
   

   3. startor mmf wave and resultant flux density wave

   
   
   

   4. none of these

   
   
   

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   NA

   Correct Option: A

   NA

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35. Two synchronous generators G₁ and G₂ are operating in parallel and sharing the load equally. To shift part of the load from G₂ to G₁ while keeping the frequency constant,
    

1. 1. lower the frequency-power characteristic of G₁ or raise that of G₂

   
   
   

   2. raise the frequency-power characteristic G₁ or lower that of G₂

   
   
   

   3. raise the frequency power characteristic of G₁ and lower that of G₂

   
   
   

   4. lower the frequency power characteristic of G₁ and raise that of G₁G₂

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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