Electronic Devices and Circuits – Multiple Choice Questions (MCQs)

1. 85. The purpose of a bypass capacitor across the emitter resistor in a BJT amplifier is to:

   • A. Increase DC voltage gain
   • B. Decrease AC voltage gain
   • C. Increase AC voltage gain
   • D. Provide stability

2. 86. The efficiency of a power supply is defined as:

   • A. Output power / Input power
   • B. Input power / Output power
   • C. Output voltage / Input voltage
   • D. Input current / Output current

3. 87. The noise figure of an amplifier is a measure of its:

   • A. Distortion
   • B. Output power
   • C. Noise generation
   • D. Input noise

4. 88. The transconductance (gm) of a BJT in the active region is directly proportional to the:

   • A. Base current
   • B. Collector current
   • C. Emitter current
   • D. Supply voltage

5. 89. Which type of amplifier provides phase inversion?

   • A. Common Emitter
   • B. Common Base
   • C. Common Collector
   • D. Voltage Follower