BASIC ELECTRONICS MCQs 2
(mcqs of basic electronics)
Q. 1 In an intrinsic semiconductor, the Fermi-level is
- (A) Closer to the valence band
- (B) Midway between conduction and valence band
- (C) Closer to the conduction band
- (D) Within the valence band
Ans: C
Q. 2 The reverse – saturation current of a silicon diode
- (A) Doubles for every 10°C increase in temperature
- (B) Does not change with temperature
- (C) Halves for every 1°C decrease in temperature
- (D) Increases by 1.5 times for every 2°C increment in temperature
Ans: A
Q. 3 The common collector amplifier is also known as
- (A) Collector follower
- (B) Base follower
- (C) Emitter follower
- (D) Source follower
Ans: C
Q. 4 In class–A amplifier, the output current flows for
- (A) A part of the cycle or the input signal.
- (B) The full cycle of the input signal.
- (C) Half the cycle of the input signal.
- (D) 3/4th of the cycle of the input signal.
Ans: B
Q. 5 In an amplifier with negative feedback
- (A) Only the gain of the amplifier is affected
- (B) Only the gain and bandwidth of the amplifier are affected
- (C) Only the input and output impedances are affected
- (D)All of the four parameters mentioned above would be affected
Ans: D
Q. 6 Wien bridge oscillator can typically generate frequencies in the range of
- (A) 1 KHz – 1MHz
- (B) 1 MHz – 10MHz
- (C) 10MHz – 100MHz
- (D) 100MHz – 150MHz
Ans: A
Q. 7 A differential amplifier, amplifies
- (A) And mathematically differentiates the average of the voltages on the two input lines
- (B) And differentiates the input waveform on one line when the other line is grounded
- (C) The difference of voltages between the two input lines
- (D) And differentiates the sum of the two input waveforms
Ans: C
Q. 8 The transformer utilization factor of a half-wave rectifier is approximately
- (A) 0.6
- (B) 0.3
- (C) 0.9
- (D) 1.1
Ans: B
0.286 ≈ 0.3
Q. 9 The dual of the Boolean expression: x + y + z is
Ans: C 
Q.10 It is required to construct a counter to count up to 100(decimal). The minimum number of flipflops required to construct the counter is
- (A) 8
- (B) 7
- (C) 6
- (D) 5
Ans: A
Q.11 The power conversion efficiency of an output stage is defined as_______.
- (A) (Load power + supply power) / supply power
- (B) (Load power + supply power) / (load power-supply power)
- (C) Load power / supply power
- (D) Supply power / load power
Ans. (C)
Power gain is defined as the ratio of output signal power to that of input signal power.
Q.12 A highly stable resonance characteristic is the property of a ____ oscillator.
- (A) Hartley
- (B) Colpitts
- (C) Crystal
- (D) Weinbridge
Ans. (C)
Q.13 The gate that assumes the 1 state, if and only ifthe input does not take a 1 state is called________.
- (A) AND gate
- (B) NOT gate
- (C) NOR gate
- (D) Both (B) & (C)
Ans. (D)
therefore output is high only when the values of both A and B are 0.
Q.14 The width of depleted region of a PN junction is of the order of a few tenths of a ___________.
- (A) Millimeter
- (B) Micrometer
- (C) Meter
- (D) Nanometer
Ans. (B)
Q.15 For NOR circuit SR flip flop the not allowed condition is ________.
- (A)S=0, R=0.
- (B)S=0, R=1.
- (C)S=1, R=1.
- (D)S=1, R=0.
Ans. (C)
When S=R=1 the output is subject to unpredictable behavior when S and R return to 0 simultaneously.
Q.16 In negative feedback the return ratio is __________.
- (A) 0
- (B) 1
- (C) Greater than 0
- (D) Greater than 1
Ans. (C)
In a negative feedback circuit, always the return ratio will be in the range of 0 to 1.
Q.17 A phase shift oscillator uses __________________.
- (A) LC tuning
- (B) Piezoelectric crystal
- (C) Balanced bridge
- (D) Variable frequency operation
Ans. (C)
Q.18 The voltage gain of basic CMOS is approximately _________.
Ans. (A)
Q.19 Transistor is a
- (A) Current controlled current device.
- (B) Current controlled voltage device.
- (C) Voltage controlled current device.
- (D) Voltage controlled voltage device.
Ans. (A)
The output current depends on the input current.
Q.20 A bistable multivibrator is a
- (A) Free running oscillator.
- (B) Triggered oscillator.
- (C) Saw tooth wave generator.
- (D) Crystal oscillator.
Ans. (B)
The transistors would change their state of operation from ON to OFF and vice versa depending on the external trigger provided.
(mcqs of basic electronics)