91. In an amplifier, the coupling capacitors are used to:

1. 1. match the impedances.

   
   
   

   2. control the output.

   
   
   

   3. limit the bandwidth.

   
   
   

   4. prevent d.c. mixing with input and output.

   
   
   

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   The main purpose of using coupling capacitor is to prevent d.c. mixing with input and output.

   Correct Option: D

   The main purpose of using coupling capacitor is to prevent d.c. mixing with input and output.

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92. The C-E amplifier is characterised by:

1. 1. low voltage gain.

   
   
   

   2. very high input impedance.

   
   
   

   3. signal phase reversal

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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93. R-C coupling is proper in low-level audio amplifier because it:

1. 1. is expensive and needs no adjustment.

   
   
   

   2. provides an output signal in phase with the input signal.

   
   
   

   3. has better low frequency response.

   
   
   

   4. needs low voltage battery for collector supply.

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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94. The main component responsible for the fall of gain of an R-C coupled amplifier in low frequency range is:

1. 1. coupling capacitor

   
   
   

   2. resistor RE

   
   
   

   3. the device (i.e. transistor)

   
   
   

   4. biasing system.

   
   
   

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   NA

   Correct Option: A

   NA

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95. Multistage amplifiers are used in order to achieve greater:

1. 1. voltage regulation

   
   
   

   2. frequency response

   
   
   

   3. power gain

   
   
   

   4. All of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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