Analog Electronics – MCQs

By: Prof. Dr. Fazal Rehman | Last updated: April 22, 2025

1. : What is the basic building block of analog electronics?
(A) Diode
(B) Transistor
(C) Inductor
(D) Resistor

2. : Which component is used to amplify signals in analog circuits?
(A) Diode
(B) Transistor
(C) Resistor
(D) Capacitor

3. : What is the typical voltage gain of an ideal operational amplifier (op-amp)?
(A) 0
(B) 1
(C) Infinite
(D) 10

4. : The input impedance of an ideal op-amp is:
(A) Zero
(B) Low
(C) Very high
(D) Medium

5. : A capacitor stores energy in the form of:
(A) Magnetic field
(B) Electric field
(C) Mechanical stress
(D) Heat

6. : Which configuration of a transistor offers high voltage and current gain?
(A) Common base
(B) Common emitter
(C) Common collector
(D) Emitter follower

7. : What is the purpose of a biasing circuit in analog electronics?
(A) To limit current
(B) To regulate voltage
(C) To set the operating point of a transistor
(D) To amplify AC signals

8. : In an RC low-pass filter, increasing the resistance will:
(A) Increase cutoff frequency
(B) Decrease cutoff frequency
(C) Have no effect
(D) Eliminate all signals

9. : The frequency at which the gain of a filter falls to 70.7% of its maximum is called:
(A) Peak frequency
(B) Resonance frequency
(C) Cutoff frequency
(D) Threshold frequency

10. : What does the term “slew rate” refer to in op-amps?
(A) The input impedance
(B) The output resistance
(C) The rate of change of output voltage
(D) The power gain

11. : Which of the following is a linear analog circuit?
(A) Comparator
(B) Oscillator
(C) Differential amplifier
(D) Schmitt trigger

12. : The output of a full-wave rectifier is:
(A) Pure DC
(B) Pulsating DC
(C) AC
(D) Zero

13. : Which device is used to convert AC to DC in analog circuits?
(A) Transistor
(B) Diode
(C) Capacitor
(D) Inductor

14. : What is the unit of gain when expressed in decibels (dB)?
(A) Amps
(B) Volts
(C) No unit
(D) dB

15. : What type of feedback is used in oscillators?
(A) Negative feedback
(B) Positive feedback
(C) No feedback
(D) Mixed feedback

16. : A zener diode is primarily used for:
(A) Rectification
(B) Signal mixing
(C) Voltage regulation
(D) Current amplification

17. : The gain-bandwidth product of an op-amp is:
(A) Always decreasing
(B) Constant
(C) Variable with voltage
(D) Zero

18. : A phase shift oscillator uses which components to create a phase shift?
(A) Resistors only
(B) Inductors and capacitors
(C) Resistors and capacitors
(D) Diodes and capacitors

19. : Which amplifier configuration has a voltage gain less than 1?
(A) Common emitter
(B) Common base
(C) Common collector
(D) Differential amplifier

20. : A transistor in active region behaves like a:
(A) Switch
(B) Variable resistor
(C) Amplifier
(D) Short circuit

21. : Which component blocks DC but allows AC to pass?
(A) Diode
(B) Resistor
(C) Capacitor
(D) Transformer

22. : Which parameter determines the sharpness of a resonance in a circuit?
(A) Gain
(B) Frequency
(C) Quality factor (Q)
(D) Slew rate

23. : What is the role of an emitter resistor in a BJT amplifier?
(A) Increase current
(B) Reduce voltage
(C) Stabilize biasing
(D) Boost gain

24. : In a BJT, current flows from:
(A) Emitter to collector
(B) Collector to emitter
(C) Base to emitter
(D) Base to collector

25. : A Class A amplifier conducts for:
(A) 90° of input cycle
(B) 180° of input cycle
(C) 270° of input cycle
(D) 360° of input cycle