Explore topic-wise MCQs in Electrical Engineering.

This section includes 130 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

51.

Three identical amplifiers with each one having a voltage gain of 50,input resistance of 1KΩ & output resistance of 250, are cascaded. The open circuit voltage gain of combined amplifier is

A. 49dB
B. 51dB
C. 98dB
D. 102dB
Answer» D. 102dB
52.

A differential amplifier is invariably used in the i/p stage of all OP-amps.This is dome basically to provide the OP-amps with a very high

A. CMRR
B. Bandwidth
C. Slew rate
D. Open-loop gain
Answer» B. Bandwidth
53.

The MOSFET switch in its onstate may be considered equivalent to

A. Resistor
B. Inductor
C. Capacitor
D. Battery
Answer» D. Battery
54.

Introducing a resistor in the emitter of a common amplifier stabilizes the dc operating point against variations in

A. Only the temperature
B. only the β of the transistor
C. Both Temperature & β
D. None of the above
Answer» D. None of the above
55.

Voltage Series (feedback also called series-shunt feedback) results in

A. Increase in both input & output impedances
B. Decreases in both input & output impedances
C. Increase in input impedance & decreases in output impedance
D. Decrease in input impedance & increase in output impedance
Answer» D. Decrease in input impedance & increase in output impedance
56.

An amplifier using an opamp with slew rate SR=1v/µsec has a gain of 40db.if this amplifier has to faithfully amplify sinusoidal signals from dc to 20 KHz without introducing any slew-rate induced distortion, then the input signal level must not exceed

A. 795mV
B. 395mV
C. 795 mV
D. 39.5mV
Answer» D. 39.5mV
57.

In a common emitter, unbypassed resister provides

A. voltage shunt feedback
B. current series feedback
C. negative voltage feedback
D. positive current feedback
Answer» D. positive current feedback
58.

An n- channel JFET has IDSS=2mA,and Vp=-4v.Its transconductance gm=in mA/V)for an applied gate to source voltage VGS=-2v is

A. 0.25
B. 0.5
C. 0.75
D. 1
Answer» C. 0.75
59.

An amplifier without feedback has a voltage gain of 50,input resistance os 1 KΩ & Output resistance of 2.5KΩ.The input resistance of the current shunt negative feedback amplifier using the above amplifier with a feedbacik factor of 0.2 is

A. 1/11KΩ
B. 1/5KΩ
C. 5KΩ
D. 11KΩ
Answer» B. 1/5KΩ
60.

Negative feedback in an amplifier

A. Reduces gain
B. Increase frequency &phase distortion
C. Reduces bandwidth
D. Increases noise
Answer» B. Increase frequency &phase distortion
61.

An npn BJT has gm=38mA/v, cµ =10¯14 F, cπ =10¯13F and DC current gain β0=90.For this transistor fT & fβ are

A. fT =1.64 x 108 Hz & fβ = 1.47 x 1010 Hz
B. fT =1.47 x 1010 Hz & fβ = 1.64 x 108 Hz
C. fT =1.33 x 1012 Hz & fβ = 1.47 x 1010 Hz
D. fT =1.47 x 1010 Hz & fβ = 1.33 x 1012 Hz
Answer» C. fT =1.33 x 1012 Hz & fβ = 1.47 x 1010 Hz
62.

A constant current signal across a parallel RLC circuits gives an o/p of 1.4v at the signal frequency of 3.89KHZ and 4.1KHZ. At the frequency of 4KHZ,the o/p voltage will be

A. 1v
B. 2v
C. 1.4v
D. 2.8v
Answer» C. 1.4v
63.

If=0.98, Ico=6µA and Iβ=100µA for a transistor,then the value of Ic will be

A. 2.3mA
B. 3.2mA
C. 4.6mA
D. 5.2mA
Answer» E.
64.

In a p⁺n junction diode under reverse bias , the magnitude of electric field is maximum at

A. The edge of the depletion region on the p-side
B. The edge of the depletion region on the n-side
C. The p⁺n junction
D. The center of the depletion region on the n-side
Answer» D. The center of the depletion region on the n-side
65.

What is the voltage source for a circuit carrying 2 A of current through a 36 Ω resistor?

A. 1.8 V
B. 18 V
C. 7.2 V
D. 72 V
Answer» E.
66.

When 12 V are applied across a 68 Ω resistor, the current is

A. 816 mA
B. 17.6 mA
C. 176 mA
D. 8.16 mA
Answer» D. 8.16 mA
67.

When there is 12 mA of current through a 1.2 kΩ resistor, the voltage across the resistor is

A. 14.4 V
B. 1.4 V
C. 100 V
D. 10 V
Answer» B. 1.4 V
68.

A current of 200 µA through a 6.8 kΩ resistor produces a voltage drop of

A. 34.4 V
B. 340 V
C. 13.6 V
D. 1.36 V
Answer» E.
69.

How much voltage is needed to produce 2.5 A of current through a 200 Ω resistor?

A. 50 V
B. 500 V
C. 80 V
D. 8 V
Answer» C. 80 V
70.

A resistance of 3.3 MO is connected across a 500 V source. The resulting current is approximately

A. 15.1 µA
B. 151 µA
C. 66 mA
D. 660 mA
Answer» C. 66 mA
71.

Approximately how much current flows through a 3.3 MO resistor across a 30 V source?

A. 9 µA
B. 90 µA
C. 900 µA
D. 9000 µA
Answer» B. 90 µA
72.

According to Ohm's Law

A. V is directly proportional to I
B. V is inversely proportional to I
C. V is directly proportional to vI
D. All of the above
Answer» B. V is inversely proportional to I
73.

If 750 µA is flowing through 11 kΩ of resistance, what is the voltage drop across the resistor?

A. 8.25 V
B. 82.5 V
C. 14.6 V
D. 146 V
Answer» B. 82.5 V
74.

Approximately how many milli-amperes of current flow through a circuit with a 40 V source and 6.8 kΩ of resistance?

A. 27.2 mA
B. 59 mA
C. 5.9 mA
D. 590 mA
Answer» D. 590 mA
75.

Four amperes of current are measured through a 24 Ω resistor connected across a voltage source. How much voltage does the source produce?

A. 960 V
B. 9.6 V
C. 96 V
D. 8 V
Answer» D. 8 V
76.

How much current is produced by a voltage of 18 kV across a 15 kΩ resistance?

A. 1.2 A
B. 12 A
C. 120 mA
D. 12 mA
Answer» B. 12 A
77.

The quantity 43 × 10-3 is the same as

A. 0.043
B. 0.430
C. 430
D. 43,000
Answer» B. 0.430
78.

The number 0.0003 multiplied by 10-3 is

A. 0.0000003
B. 0.0003
C. 3
D. 3,000
Answer» B. 0.0003
79.

The number 4.38 × 10–3 expressed as a number having a power of 10–6 is

A. 4,380 × 10–6
B. 438 × 10–6
C. 43,800 × 10–6
D. 438,000 × 10–6
Answer» B. 438 × 10–6
80.

What is (79 × 106)/(12 × 10-8)?

A. 6,580 × 1012
B. 658 × 1010
C. 6.58 × 1014
D. 0.658 × 1016
Answer» D. 0.658 × 1016
81.

The quantity 3.3 × 103 is the same as

A. 330
B. 3,300
C. 33,000
D. 0.0033
Answer» C. 33,000
82.

The number 3.2 × 10–5 A expressed using a metric prefix is

A. 32 µA
B. 3.3 µA
C. 320 mA
D. 3,200 mA
Answer» B. 3.3 µA
83.

When these numbers are added, (87 × 105) + (2.5 × 106), the result is

A. 1.12 × 104
B. 11.2 × 105
C. 112 × 105
D. 1,120 × 106
Answer» D. 1,120 × 106
84.

The number 4.4 × 106 ohms expressed using a metric prefix is

A. 4 k
B. 4.4 k
C. 4 M
D. 4.4 M
Answer» E.
85.

When these numbers are multiplied, (6 × 103) (5 × 105), the result is

A. 3 × 108
B. 30 × 108
C. 300 × 109
D. 3,000 × 107
Answer» C. 300 × 109
86.

When diodes are connected in series to increase voltage rating the peak inverse voltage per junction%!

A. should not exceed half the breakdown voltage
B. should not exceed the breakdown voltage
C. should not exceed one third the breakdown voltage
D. may be equal to or less than breakdown voltage
Answer» D. may be equal to or less than breakdown voltage
87.

In monolithic ICs, all the components are fabricated by%!

A. Diffusion process
B. Oxidation
C. Evaporation
D. None
Answer» B. Oxidation
88.

Fermi level is the amount of energy in which%!

A. A hole can have at room temperature
B. An electron can have at room temperature
C. Must be given to an electron move to conduction band
D. None of the above
Answer» D. None of the above
89.

Free electrons exist in%!

A. First band
B. Second band
C. Third band
D. Conduction band
Answer» E.
90.

The output, V-I characteristics of an Enhancement type MOSFET has%!

A. Only an ohmic region
B. Only a saturation region
C. An ohmic region at low voltage value followed by a saturation region at higher voltages
D. An ohmic region at large voltage values preceded by a saturation region at lower voltages
Answer» D. An ohmic region at large voltage values preceded by a saturation region at lower voltages
91.

Which variety of copper has the best conductivity?%!

A. Pure annealed copper
B. Hard drawn copper
C. Induction hardened copper
D. Copper containing traces of silicon
Answer» B. Hard drawn copper
92.

Work function is the maximum energy required by the fastest electron at 0 K to escape from the metal surface.%!

A. True
B. False
Answer» C.
93.

When avalanche breakdown occurs covalent bonds are not affected.%!

A. True
B. False
Answer» C.
94.

In a bipolar transistor, the base collector junction has%!

A. Forward bias
B. Reverse bias
C. Zero bias
D. Zero or forward bias
Answer» C. Zero bias
95.

Silicon is not suitable for fabrication of light emitting diodes because it is%!

A. An indirect band gap semiconductor
B. Direct band gap semiconductor
C. Wideband gap semiconductor
D. Narrowband gap semiconductor
Answer» B. Direct band gap semiconductor
96.

Assertion (A): A p-n junction has high resistance in reverse direction.Reason (R): When a reverse bias is applied to p-n junction, the width of depletion layer increases.%!

A. Both A and R are true and R is correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true
Answer» B. Both A and R are true but R is not a correct explanation of A
97.

Power diodes are generally%!

A. Silicon diodes
B. Germanium diodes
C. Either of the above
D. None of the above
Answer» B. Germanium diodes
98.

A transistor has a current gain of 0.99 in the CB mode. Its current gain in the CC mode is%!

A. 100
B. 99
C. 1.01
D. 0.99
Answer» B. 99
99.

*/*_Each cell of a static Random Access memory contains?

A. 6 MOS transistor
B. 4 MOS transistor, 2 capacitor
C. 2 MOS transistor, 4 capacitor
D. 1 MOS transistor and 1 capacitor
Answer» B. 4 MOS transistor, 2 capacitor
100.

*/*_At room temperature the current in an intrinsic semiconductor is due to?

A. Holes
B. Electrons
C. Ions
D. Holes and electrons
Answer» E.