46. The major application of chopper drive is in—
    

1. 1. Traction
      

   
   
   

   2. Computers
      

   
   
   

   3. Heating furnaces
      

   
   
   

   4. Miniature motors

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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47. A Power MOSFET is a—
    

1. 1. Voltage controlled device
      

   
   
   

   2. Current controlled device
      

   
   
   

   3. Frequency controlled device
      

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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48. Which of the following regulator provides output voltage polarity reversal without a transformer?
    

1. 1. Buck regulator
      

   
   
   

   2. Boost regulator
      

   
   
   

   3. Buck-Boost regulator
      

   
   
   

   4. Cuk regulator

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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49. The efficiency of a chopper can be expected in the range:
    

1. 1. 50 to 55 per cent
      

   
   
   

   2. 65 to 72 per cent
      

   
   
   

   3. 82 to 87 per cent
      

   
   
   

   4. 92 to 99 per cent

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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50. A 1 – φ full bridge diode rectifier delivers a load current of 10 A, which is ripple free. Average and rms values of diode currents are respectively—
    

1. 1. 10 A, 7·07 A
      

   
   
   

   2. 5A, 10 A
      

   
   
   

   3. 5A, 7·07 A
      

   
   
   

   4. 7·07 A, 5A

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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