Explore topic-wise MCQs in Electronics & Communication Engineering.

This section includes 111 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics & Communication Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

A bandpass filter uses ________ circuit.

A. a high-pass
B. a low-pass
C. a high-pass and a low-pass
D. neither a low-pass nor a high-pass
Answer» D. neither a low-pass nor a high-pass
Discussion
2.

The roll-off for a second-order high-pass filter is ________.

A. either –20 dB per decade or –6 dB per octave
B. either –40 dB per decade or –12 dB per octave
C. either –60 dB per decade or –18 dB per octave
D. None of the above
Answer» C. either –60 dB per decade or –18 dB per octave
Discussion
3.

A filter that passes signals that are above one ideal cutoff frequency and below a second cutoff frequency is called ________.

A. low-pass
B. high-pass
C. bandpass
D. band reject
Answer» D. band reject
Discussion
4.

The roll-off for a first-order high-pass filter is ________.

A. –20 dB/decade
B. –6 dB/octave
C. either –20 dB/decade or –6 dB/octave
D. None of the above
Answer» D. None of the above
Discussion
5.

A low-pass filter ________.

A. provides a constant output up to the cutoff frequency
B. passes frequencies from zero up to the cutoff frequency
C. rejects all frequencies above the cutoff frequency
D. All of the above
Answer» E.
Discussion
6.

An active circuit is composed of a(n) ________.

A. resistor
B. capacitor
C. op-amp
D. All of the above
Answer» E.
Discussion
7.

A(n) ________ is not a component of a passive filter.

A. op-amp
B. capacitor
C. inductor
D. resistor
Answer» B. capacitor
Discussion
8.

In an instrumentation amplifier, the output voltage is based on the ________ times a scale factor.

A. summation of the two inputs
B. product of the two inputs
C. difference between the two inputs
D. None of the above
Answer» D. None of the above
Discussion
9.

In a millivoltmeter, the diodes and the capacitor are used in ________ parts of the circuit.

A. the dc
B. the ac
C. both the dc and ac
D. neither the dc nor ac
Answer» C. both the dc and ac
Discussion
10.

In a dc millivoltmeter, the amplifier provides a meter with ________ input impedance and a scale factor dependent on ________ value and accuracy.

A. high, resistor
B. low, resistor
C. high, capacitor
D. None of the above
Answer» B. low, resistor
Discussion
11.

In a current-controlled current source, the controlled current Io depends on ________.

A. I1
B. R1
C. R2
D. All of the above
Answer» E.
Discussion
12.

Op-amp circuits are used in ________ voltmeters.

A. only dc
B. only ac
C. both ac and dc
D. neither ac nor dc
Answer» D. neither ac nor dc
Discussion
13.

In a current-controlled voltage source using the inverting op-amp circuit, the controlled output current is ________ with the input voltage source.

A. in phase
B. 45º out of phase
C. 90º out of phase
D. 180º out of phase
Answer» B. 45º out of phase
Discussion
14.

________ can be used as a voltage-controlled voltage source.

A. Only an inverting op-amp circuit
B. Only a noninverting op-amp circuit
C. Neither inverting nor noninverting op-amp circuits
D. Both inverting and noninverting op-amp circuits
Answer» E.
Discussion
15.

________ in a current-controlled voltage source circuit.

A. The input current depends on the output voltage
B. The input current depends on the input voltage source
C. The output voltage depends on the input current.
D. The output current depends on the output voltage source
Answer» D. The output current depends on the output voltage source
Discussion
16.

The output impedance of a voltage buffer is ________.

A. very low
B. low
C. high
D. very high
Answer» C. high
Discussion
17.

Op-amps can be used to form ________ circuit(s).

A. voltage-controlled voltage source
B. voltage-controlled current source
C. current-controlled voltage source
D. All of the above
Answer» E.
Discussion
18.

The input impedance of a voltage buffer is ________.

A. very low
B. low
C. high
D. very high
Answer» E.
Discussion
19.

The output voltage of a voltage buffer is ________ with the input voltage.

A. in phase
B. 45º out of phase
C. 90º out of phase
D. 180º out of phase
Answer» B. 45º out of phase
Discussion
20.

The voltage gain of a voltage buffer is ________ .

A. 1
B. 0
C. –1
D. –5
Answer» B. 0
Discussion
21.

________ build a multistage connection.

A. Only an inverting op-amp circuit must be used to
B. Only a noninverting op-amp circuit must be used to
C. Both inverting and noninverting op-amp circuits can be used to
D. Neither inverting nor noninverting op-amp circuits must be used to
Answer» D. Neither inverting nor noninverting op-amp circuits must be used to
Discussion
22.

A voltage summing amplifier has ________.

A. several inputs and several outputs
B. several inputs and one output
C. one input and several outputs
D. one input and one output
Answer» C. one input and several outputs
Discussion
23.

When a number of stages are connected in series, the overall gain is the ________ of the individual stage gains.

A. sum
B. product
C. difference
D. average
Answer» C. difference
Discussion
24.

The input to an op-amp can be a(n) ________.

A. dc source
B. ac source
C. combination of ac and dc sources
D. All of the above
Answer» E.
Discussion
25.

The level of the output voltage of an op-amp circuit is always ________ the level of VCC.

A. larger than
B. the same as
C. smaller than
D. None of the above
Answer» D. None of the above
Discussion
26.

Calculate the cutoff frequencies of a bandpass filter with R1 = R2 = 5 k and C1 = C2 = 0.1 F.

A. fOL = 318.3 Hz, fOH = 318.3 Hz
B. fOL = 636.6 Hz, fOH = 636.6 Hz
C. fOL = 318.3 Hz, fOH = 636.6 Hz
D. fOL = 636.6 Hz, fOH = 318.3 Hz
Answer» B. fOL = 636.6 Hz, fOH = 636.6 Hz
Discussion
27.

Calculate the cutoff frequency of a first-order low-pass filter for R1 = 2.5 k and C1 = 0.05 F.

A. 1.273 kHz
B. 12.73 kHz
C. 127.3 kHz
D. 127.30 Hz
Answer» B. 12.73 kHz
Discussion
28.

Calculate the output voltage for this circuit when V1 = 2.5 V and V2 = 2.25 V.

A. –5.25 V
B. 2.5 V
C. 2.25 V
D. 5.25 V
Answer» E.
Discussion
29.

How many op-amps are required to implement this equation? Vo = V1

A. 2
B. 3
C. 4
D. 1
Answer» E.
Discussion
30.

Calculate IL for this circuit.

A. 3 mA
B. 4 mA
C. 5 mA
D. 6 mA
Answer» D. 6 mA
Discussion
31.

Determine the output voltage when V1 = –V2 = 1 V.

A. 0 V
B. –2 V
C. 1 V
D. 2 V
Answer» C. 1 V
Discussion
32.

Determine the output voltage when V1 = –V2 = –1 V.

A. 0 V
B. –2 V
C. 1 V
D. 2 V
Answer» E.
Discussion
33.

Determine the output voltage when V1 = V2 = 1 V.

A. 0 V
B. –2 V
C. 1 V
D. 2 V
Answer» B. –2 V
Discussion
34.

Calculate the output voltage Vo if V1 = –V2 = 300 mV.

A. 0 V
B. –6 V
C. 6 V
D. –8 V
Answer» D. –8 V
Discussion
35.

Calculate the output voltage if V1 = V2 = 700 mV.

A. 0 V
B. –12 V
C. 12 V
D. –8 V
Answer» B. –12 V
Discussion
36.

Calculate the output voltage if V1 = 300 mV and V2 = 700 mV.

A. 0 V
B. –12 V
C. 12 V
D. –4 V
Answer» E.
Discussion
37.

Calculate the output voltage if V1 = –0.2 V and V2 = 0 V.

A. 0 V
B. –6.6 V
C. –4 V
D. 2 V
Answer» E.
Discussion
38.

Calculate the output voltage if V1 = 0 V and V2 = 0.2 V.

A. 0 V
B. –6.6 V
C. –4 V
D. 2 V
Answer» C. –4 V
Discussion
39.

Calculate the output voltage if V1 = 33 mV and V2 = 2 mV.

A. 0 V
B. –6.6 V
C. –0.4 V
D. 2 V
Answer» D. 2 V
Discussion
40.

Calculate the output voltage if V1 = –3.3 V and V2 = 0.8 V.

A. 0 V
B. 6.6 V
C. –4 V
D. 2 V
Answer» C. –4 V
Discussion
41.

Calculate the output voltage if V1 = V2 = 0.15 V.

A. 0 V
B. 4.65 V
C. 6.45 V
D. –6.45 V
Answer» E.
Discussion
42.

Determine the value of Rf (assuming that all have the same value).

A. 500 k
B. 50 k
C. 25 k
D. 5 k
Answer» C. 25 k
Discussion
43.

Calculate the output of the first-stage op-amp when V1 = 25 mV.

A. –1.05 V
B. 0.075 V
C. 0.06 V
D. 4.2 V
Answer» C. 0.06 V
Discussion
44.

Calculate the output of the second stage op-amp if V1 = 25 mV.

A. –0.075 V
B. 0.525 V
C. 0.06 V
D. 4.2 V
Answer» B. 0.525 V
Discussion
45.

Calculate the input voltage when Vo = 11 V.

A. 1.1 V
B. –1.1 V
C. –1 V
D. 1 V
Answer» E.
Discussion
46.

Calculate the input voltage for this circuit if Vo = –11 V.

A. 1.1 V
B. –1.1 V
C. –1 V
D. 1 V
Answer» B. –1.1 V
Discussion
47.

Identify the circuit

A. low pass filter
B. high pass filter
C. bandpass filter
D. band stop filter
Answer» C. bandpass filter
Discussion
48.

If the gain of a closed-loop inverting amplifier is 3.9 (magnitude) with an input resistor value of 1.6 K ohms, what value of feedback resistor is necessary ?

A. 2.4 K ohms
B. 6.24 K ohms
C. 0.62 K ohms
D. 410 ohms
Answer» C. 0.62 K ohms
Discussion
49.

Input resistances Ri of ideal voltage amplifier and ideal current amplifier are respectively

A. ∞, 0
B. 0, ∞
C. ∞, ∞
D. 0, 0
Answer» B. 0, ∞
Discussion
50.

Monostable multivibrator may be used to generate

A. sweep voltage
B. pulses
C. sinusoidal voltage
D. sweep current
Answer» C. sinusoidal voltage
Discussion