Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

For the circuit in figure the output wave shape is

A. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/315-206-2.png">
B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/315-206-3.png">
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/315-206-4.png">
D. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/315-206-5.png">
Answer» E.
Discussion
2.

In figure, ID = 4 mA. Then VS =

A. 20 V
B. 16 V
C. 6 V
D. 0.6 V
Answer» D. 0.6 V
Discussion
3.

For an npn transistor connected as shown in the figure VBE = 0.7 volts. Given that reverse saturation current of the junction at room temperature 300K is 10-13A, the emitter current.

A. 30 mA
B. 39 mA
C. 49 mA
D. 20 mA
Answer» D. 20 mA
Discussion
4.

The dc output voltage of the circuit is

A. 4.3 V
B. 1.369 V
C. 3.87 V
D. 1.94 V
Answer» C. 3.87 V
Discussion
5.

A voltage doubler circuit is fed by a voltage Vm sin t. The output voltage will be nearly 2 Vm only if

A. load resistance is small
B. load resistance is large
C. load resistance is neither small nor large
D. either (a) or (c)
Answer» C. load resistance is neither small nor large
Discussion
6.

The purpose of connecting a coupling capacitor in the output circuit of an amplifier is

A. to increase voltage gain
B. to increase collector current
C. to block dc collector voltage
D. all of the above
Answer» D. all of the above
Discussion
7.

Which component is allowed to pass through it by a choke filter?

A. Dc
B. Ac
C. Both dc and ac
D. Only high frequency ac
Answer» B. Ac
Discussion
8.

In an amplifier the stray capacitances assume impedance at low frequencies

A. True
B. False
Answer» C.
Discussion
9.

Which op-amp circuit uses a capacitor in series with input and resistance in feedback path?

A. Differentiating amplifier
B. Integrating amplifier
C. Logarithmic amplifier
D. None of the above
Answer» B. Integrating amplifier
Discussion
10.

For class B operation the theoretical maximum efficiency is

A. 100%
B. 78.5%
C. 50%
D. 27.5%
Answer» C. 50%
Discussion
11.

To draw ac equivalent circuit for a CE amplifier we should

A. Reduce all dc sources to zero
B. Short all capacitors
C. Reduce all dc sources to zero and short all capacitors
D. Reduce all dc sources to zero and open all capacitors
Answer» D. Reduce all dc sources to zero and open all capacitors
Discussion
12.

In the circuit of figure, the value of re is (neglecting vbe)

A. 100 &ohm;
B. 75 &ohm;
C. 50 &ohm;
D. 25 &ohm;
Answer» E.
Discussion
13.

In figure gain bandwidth product is

A. 200 Hz
B. 200 MHz
C. 200 kHz
D. 2 MHz
Answer» D. 2 MHz
Discussion
14.

The h parameter equivalent circuit of BJT has one voltage source and one current source.

A. True
B. False
Answer» B. False
Discussion
15.

The voltage eo indicated in the figure has been measured by an ideal voltmeter. Which of the following can be calculated?

A. Bias current of inverting input only
B. Bias current of inverting and non-inverting inputs only
C. Input offset current only
D. Both the bias currents and the I/P offset current
Answer» D. Both the bias currents and the I/P offset current
Discussion
16.

The circuit of figure is

A. Precision integrator
B. Hartley oscillator
C. Butterworth high pass filter
D. Wien bridge oscillator
Answer» E.
Discussion
17.

An ideal voltage amplifier should have

A. low input impedance and high output impedance
B. high input impedance and low output impedance
C. high input impedance and high output impedance
D. low input impedance and low output impedance
Answer» C. high input impedance and high output impedance
Discussion
18.

The minimum gate source voltage that creates the n-type inversion layer is called

A. cut off voltage
B. on voltage
C. threshold voltage
D. zener voltage
Answer» D. zener voltage
Discussion
19.

If a class C power amplifier has an input signal with frequency of 200 kHz and the width of collector current pulses of 0.1 ms, then the duty cycle of the amplifier will be

A. 1%
B. 2%
C. 10%
D. 20%
Answer» E.
Discussion
20.

At midband frequencies the coupling capacitor in RC coupled CE amplifier may be considered as

A. open circuit
B. short circuit
C. a reactance equal to load resistance
D. none of the above
Answer» C. a reactance equal to load resistance
Discussion
21.

The bandwidth of an amplifier is BW, of n-stage of such as amplifier are cascaded, the bandwidth will become

A. <i>n</i>
B. BW
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/343-683-1.png">
D. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/343-683-2.png">
E. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/343-683-3.png">
Answer» E. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/343-683-3.png">
Discussion
22.

Assertion (A): The gain of an FET amplifier can be changed by changing gmReason (R): Most receivers use automatic gain control to counteract changes in volume caused by fading

A. Both A and R are correct and R is correct explanation for A
B. Both A and R are correct but R is not correct explanation for A
C. A is correct R is wrong
D. A is wrong R is correct
Answer» C. A is correct R is wrong
Discussion
23.

The signal input to a given amplifier is made up of 100 m&amp;ohm; signal power and 1 m&amp;ohm; noise power. The amplifier contributes an additional 100 m&amp;ohm; of noise and has a power gain of 20 dB. The noise factor is

A. 1
B. 1.5
C. 2.0
D. 15
Answer» D. 15
Discussion
24.

The element in the feedback circuit of a logarithmic amplifier using op-amp is

A. a resistor
B. a capacitor
C. an inductor
D. a diode
Answer» E.
Discussion
25.

For the amplifier in figure, = 800. The mid-band voltage gain V0/Vi is

A. 0
B. < 1
C. 1
D. 800
Answer» D. 800
Discussion
26.

Assertion (A): Class A and Class B amplifier predominate in audio applications.Reason (R): Class C amplifier is used at radio frequencies.

A. Both A and R are correct and R is correct explanation for A
B. Both A and R are correct but R is not correct explanation for A
C. A is correct R is wrong
D. A is wrong R is correct
Answer» C. A is correct R is wrong
Discussion
27.

Class C amplifier is suitable for

A. a narrow frequency band
B. a wide frequency band
C. audio frequencies
D. either (b) or (c)
Answer» B. a wide frequency band
Discussion
28.

In a N-P-N transistor, when emitter junction is forward biased and collector junction is reverse biased the transistor will operate in

A. active region
B. saturation region
C. cut-off region
D. inverted region
Answer» B. saturation region
Discussion
29.

A Wien bridge is suitable for

A. audio frequencies only
B. radio frequencies only
C. both audio and radio frequencies
D. very low frequencies only
Answer» B. radio frequencies only
Discussion
30.

In a crystal

A. the frequencies of series and parallel resonance are equal
B. the frequency of series resonance is more than frequency of parallel resonance
C. the frequency of parallel resonance is more than frequency of series resonance
D. None of the above
Answer» D. None of the above
Discussion
31.

When Z1 &lt;&lt; Z, The circuit of figure works as

A. inverting amplifier
B. Schmitt trigger
C. non-inverting amplifier
D. source follower
Answer» E.
Discussion
32.

In a class C operation VCC = 40 V, RL = 50 &amp;ohm;. The maximum load power can be

A. 64 W
B. 32 W
C. 16 W
D. 8 W
Answer» D. 8 W
Discussion
33.

IF VCC = 15 V, VCEQ = 5 V and ICQ = 50 mA, the efficiency in class A operation is

A. 100%
B. 50%
C. 25%
D. 16.7%
Answer» E.
Discussion
34.

Which of the following best represents the bandwidth of an actual op-amp?

A. 100 Hz to 1 MHz
B. 0 Hz to 100 kHz
C. 0 Hz to 10 MHz
D. 0 Hz to infinity
Answer» C. 0 Hz to 10 MHz
Discussion
35.

An ideal op-amp can amplify dc signals

A. True
B. False
Answer» B. False
Discussion
36.

Consider the following statements :The lower cut off frequencies of an RC coupled amplifier depend on input and output coupling capacitoremitter by pass capacitorsjunction capacitances Which of the above are correct?

A. 1 only
B. 2 only
C. 1 and 2
D. 2 and 3
Answer» B. 2 only
Discussion
37.

Assertion (A): In a circuit using FET, gate is approximately at dc groundReason (R): Self bias stabilizes the quiescent operating point against changes in JFET parameters

A. Both A and R are correct and R is correct explanation for A
B. Both A and R are correct but R is not correct explanation for A
C. A is correct R is wrong
D. A is wrong R is correct
Answer» C. A is correct R is wrong
Discussion
38.

The Darlington pair consists of the following two stages

A. CE and CC
B. both CE
C. both CC
D. CE and CB
Answer» D. CE and CB
Discussion
39.

Which of the following couplings may cause unwanted clamping?

A. Resistive
B. Inductive
C. Capacitive
D. Both (a) or (b)
Answer» D. Both (a) or (b)
Discussion
40.

Figure represents

A. Adder
B. Multiplier
C. Subtractor
D. Log Amplifier
Answer» D. Log Amplifier
Discussion
41.

Which of the following contributes to harmonics distortion in amplifiers?

A. Positive feedback
B. Presence of noise
C. Defective active device
D. Non-linearity in active device
Answer» E.
Discussion
42.

The conversion or collector circuit efficiency is a measure

A. how successfully the active device converts D.C. power to A.C. signal power
B. how much distortion in output is reduced with respect to input
C. how successfully the active device converts A.C. power to D.C. signal power
D. none of the above
Answer» B. how much distortion in output is reduced with respect to input
Discussion
43.

Volt equivalent temperature in a PN Junction diode is

A. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/332-509-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/332-509-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/332-509-3.png">
D. 11600 T
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/332-509-2.png">
Discussion
44.

A transistor amplifier is operating in class A mode. If a transformer is connected for impedance matching, the efficiency will

A. increase
B. decrease
C. not be affected
D. increase or decrease
Answer» B. decrease
Discussion
45.

RECTIFIER : OSCILLATOR ::

A. Capacitance : Inductance
B. Series resonance : Parallel resonance
C. DC : AC
D. Regulation : Efficiency
Answer» E.
Discussion
46.

Which amplifier will be preferred for highest gain?

A. Darlington's pair
B. Single stage amplifier
C. Cascade amplifier
D. Depends on the circuitry
Answer» D. Depends on the circuitry
Discussion
47.

Which of the following are synonymous?

A. MOSFET and IGEFT
B. FET and JFET
C. JFET and MOSFET
D. P-N-P and N-P-N
Answer» B. FET and JFET
Discussion
48.

A voltage doubler circuit uses

A. two diodes
B. two capacitors
C. two diodes and two capacitors
D. none of the above
Answer» D. none of the above
Discussion
49.

The pinch-off voltage is the drain voltage on the shorted gate drain curve above which the drain current becomes

A. almost negligible
B. very high
C. almost constant
D. highly variable
Answer» D. highly variable
Discussion
50.

A transconductance amplifier has

A. high input impedance and low output impedance
B. low input impedance and high output impedance
C. high input and output impedance
D. low input and output impedance
Answer» D. low input and output impedance
Discussion