Explore topic-wise MCQs in Electrical Engineering.

This section includes 113 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

What is the “power factor”?

A. ratio of true power to apparent power
B. peak power times 0.707
C. sin of the phase difference between E and I
D. cos of the phase angle between true power and apparent power
Answer» B. peak power times 0.707
2.

Which of the following is one of the functions performed by a diode?

A. filter
B. amplifier
C. rectifier
D. inverter
Answer» D. inverter
3.

One coulomb-per-second is equal to one:

A. watt
B. joule
C. volt
D. ampere
Answer» E.
4.

An ideal diode should have

A. Zero resistance in the forward bias as well as reverse bias
B. Zero resistance in the forward bias and an infinitely large resistance in reverse bias
C. Infinitely large resistance in reverse bias
D. Infinitely large resistance in forward as well as reverse bias
Answer» C. Infinitely large resistance in reverse bias
5.

An ideal power supply is characterized by

A. Very large output resistance
B. Very small output resistance
C. Zero internal resistance
D. Infinite internal resistance
Answer» D. Infinite internal resistance
6.

A series capacitance used in a filter circuit represents

A. Low-Pass
B. Band-Pass
C. High-Pass
D. None
Answer» D. None
7.

To increase the input resistance and decrease the output resistance in negative feedback, the type used is

A. Voltage Shunt
B. Current Series
C. Voltage Series
D. Current Shunt
Answer» D. Current Shunt
8.

In Bipolar Junction transistors, the type of configuration which will give both voltage gain and current gain is

A. CC
B. CB
C. CE
D. None
Answer» D. None
9.

FET is a good signal chopper because

A. It exhibits no offset voltage at zero drain current
B. It occupies less space in integrated form
C. It is less noisy
D. It has got high input impedance
Answer» B. It occupies less space in integrated form
10.

To prepare a P type semiconducting material the impurities to be added to silicon are

A. Boron, Gallium
B. Arsenic, Antimony
C. Gallium, Phosphorous
D. Gallium, Arsenic
Answer» B. Arsenic, Antimony
11.

Semi-conductor diode time constant is equal to

A. The value of majority carrier life time
B. The life time of minority carrier
C. The diffusion capacitance time constant
D. Zero
Answer» B. The life time of minority carrier
12.

An emitter follows has

A. High input impedance and high output impedance.
B. High input impedance and low output impedance
C. Low input impedance and high output impedance
D. Low input impedance and low output impedance.
Answer» B. High input impedance and low output impedance
13.

An amplifier has a gain of 10,000 expressed in decibels the gain is

A. 10
B. 40
C. 80
D. 100
Answer» E.
14.

An SCR is a device having

A. Three layers with four junctions
B. Three layers with two junctions
C. Four layers with three junctions
D. Two layers with three junctions
Answer» D. Two layers with three junctions
15.

A Zener diode is used for

A. Voltage Regulation
B. Rectification
C. Noise Suppression
D. Blocking A.C
Answer» B. Rectification
16.

A dc power supply has no-load voltage of 30V and a full-load voltage of 25V at full-load current of 1A. Its output resistance and load regulation respectively are

A. 5Ω & 20%
B. 25Ω & 20%
C. 5Ω &16.7%
D. 25Ω & 16.7%
Answer» C. 5Ω &16.7%
17.

Negative feedback in an amplifier

A. Reduces gain
B. Increase frequency and phase distortion
C. Reduces bandwidth
D. Increase Noise
Answer» B. Increase frequency and phase distortion
18.

Most of the linear ICs are based on the two-transistor differential amplifier because of its

A. Input voltage dependent linear transfer characteristics
B. High voltage gain
C. High input resistance
D. High CMMR
Answer» E.
19.

The bandwidth of an RF tuned amplifier is dependent on

A. Q-factor of the tuned O/P circuit
B. Q-factor of the tuned I/P circuit
C. Quiescent operating point
D. Q-factor of the O/P and I/P circuits as well as quiescent operating point
Answer» B. Q-factor of the tuned I/P circuit
20.

Class AB operation is often used in power (large signal) amplifiers in order to

A. Get maximum effeciency
B. Remove even harmonics
C. Overcome a crossover distortion
D. Reducing collector dissipation
Answer» D. Reducing collector dissipation
21.

A constant current signal across a parallel RLC circuits gives an o/p of 1.4V at the signal frequency of 3.89kHz. At the frequency of 4 kHz, the o/p voltage will be

A. 1 V
B. 2 V
C. 1.4 V
D. 2.8 V
Answer» C. 1.4 V
22.

In a common emitter, unbypassed resistor provides

A. Voltage shut feedback
B. Current series feedback
C. Negative voltage feedback
D. Positive current feedback
Answer» D. Positive current feedback
23.

Generally, the gain of a transistor amplifier falls at high frequencies due to the

A. Internal Capacitance of the device
B. Coupling capacitor at the input
C. Skin effect
D. Coupling capacitor at the output
Answer» B. Coupling capacitor at the input
24.

A change in the value of the emitter resistance Re in a differential amplifier

A. Affects the difference mode gain Ad
B. Affects the common mode gain Ac
C. Affects both Ad and Ac
D. Does not effect either Ad and Ac
Answer» C. Affects both Ad and Ac
25.

The action of JFET in its equivalent circuit can be represented as a

A. Current controlled Current source
B. Current controlled Voltage source
C. Voltage controlled Voltage source
D. Voltage controlled Current source
Answer» E.
26.

Negative feedback in amplifiers

A. Improves the signal to noise ratio at the input
B. Improves the signal to noise ratio at the output
C. Does not affect the signal to noise ratio at the output
D. Does not affect the signal to noise ratio at the input
Answer» C. Does not affect the signal to noise ratio at the output
27.

Cut off frequency of a bipolar transistor ____

A. Increase with the increase in base width
B. Increase with the increase in emitter width
C. Increase with the increase in the collector width
D. Increase with the decrease in the base width
Answer» E.
28.

To obtain very high input & output impedances in a feedback amplifier, the topology used is

A. Voltage-Series
B. Current-Series
C. Voltage-Shunt
D. Current-Shunt
Answer» D. Current-Shunt
29.

A Zener diode works on the principle of ______

A. Tunneling of charge carriers across the junction
B. Thermionic emission
C. Diffusion of charge carriers across the junction
D. Hopping of charge carriers across the junction
Answer» B. Thermionic emission
30.

A MOS capacitor made using P-type substrate is in the accumulation mode. The dominant charge in the channel is due to the presence of

A. Holes
B. Electrons
C. Positively charged ions
D. Negatively charged ions
Answer» C. Positively charged ions
31.

The impurity commonly used for realizing the base region of a silicon NPN transistor is ______

A. Gallium
B. Indium
C. Boron
D. Phosphorus
Answer» D. Phosphorus
32.

When a junction is formed between a metal and a semiconductor, the depletion layer is

A. More on the side of the metal
B. Equal on both sides
C. Less on the side of the metal
D. Less on semiconductor side
Answer» D. Less on semiconductor side
33.

For an ideal noise free amplifier, the noise figure is

A. Zero
B. Zero dB
C. Infinity
D. 1 dB
Answer» C. Infinity
34.

In a saturated transistor

A. B-E junction is forward biased with C-B junction is reverse biased
B. Both the junctions are forward biased
C. B-E junction is reverse biased with C-B junction is forward biased
D. Both the junctions are reverse biased
Answer» C. B-E junction is reverse biased with C-B junction is forward biased
35.

In a voltage series feedback

A. Output resistance increases while input resistance decreases
B. Output and input resistances are reduced
C. Output and input resistances are increased
D. Output resistance decreases while input resistance increases
Answer» C. Output and input resistances are increased
36.

H-parameters of a transistor

A. Are constant
B. Vary with temperature
C. Are dependent upon collector current
D. None of these
Answer» D. None of these
37.

In FET amplifiers, input is Incorrect!

A. A current signal
B. A voltage signal
C. Either a current or voltage signal
D. None of these
Answer» C. Either a current or voltage signal
38.

Zener diodes semiconductors are

A. Lightly Doped
B. Heavily Doped
C. Medium Doped
D. Not at all Doped
Answer» C. Medium Doped
39.

For harmonic generation the amplifier used is

A. Audio Amplifier
B. Class-A Amplifier
C. RC Amplifier
D. class-C Turned Amplifier
Answer» E.
40.

Which one of the following conditions for Z parameters would hold for a two port network containing linear bilateral passive circuit elements?

A. Z11 = Z22
B. Z12Z21 = Z11Z22
C. Z11Z12 = Z22Z21
D. Z12 = Z21
Answer» E.
41.

A transistor has CE parameter as hie = 10kW, hre=20 x 10-4 , hse = 100, hoe = 25 ms. The hib for this transistor will be

A. 100 W
B. 99.01 W
C. 5m W
D. 101kW
Answer» C. 5m W
42.

When an RC driving point impedance function has zeros at s= -2 and s=-5 then the admissible poles for the function would be?

A. s = 0; s = -6
B. s = 0; s = -3
C. s = 0; s = -1
D. s = -3; s = -4
Answer» C. s = 0; s = -1
43.

When a sample of germanium and silicon having same impurity density are kept at room temperature then?

A. Both will have equal value of resistivity
B. Both will have equal value negative resistivity
C. Resistivity of germanium will be higher than that of silicon
D. Resistivity of silicon will be higher than that of germanium
Answer» E.
44.

When a piece of copper and another of germanium are cooled from room temperature to 800 K then the resistance of -

A. Each of them increases
B. Each of them decreases
C. Copper increases and germanium decreases
D. Copper decreases and germanium increases
Answer» E.
45.

Clipper circuits are used to obtain any one of the following waveforms

A. Sharper
B. Rectified
C. Fast Rising
D. Smaller Amplitude
Answer» E.
46.

By passing a triangular wave through a differentiating circuit the output wave shape is

A. Spikes
B. Squarewave
C. Sawtooth
D. Sinewave
Answer» B. Squarewave
47.

In an RL circuit after a very long time of application of step voltage the inductance L is represented in its equivalent circuit as Incorrect!

A. Open Circuit
B. Short Circuit
C. L / 2
D. 2L
Answer» C. L / 2
48.

Alternatively the characteristic impedance is called

A. Surge Impedance
B. Match Impedance
C. Alternative Impedance
D. Reflected Impedance
Answer» B. Match Impedance
49.

The amplifier is which current is proportional to the signal voltage, independent of source load resistance is called

A. Current Amplifier
B. Voltage Amplifier
C. Transresistance amplifier
D. Transconductance amplifier
Answer» D. Transconductance amplifier
50.

TVS diode is used for

A. Voltage protection
B. Current protection
C. ESD protection
D. None of the above
Answer» B. Current protection