Explore topic-wise MCQs in Electrical Engineering.

This section includes 682 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.

The time constant and R-C circuit may also be defined as the time during which thecharging current falls to percent of its initial maximum value,

A. 37
B. 42
C. 63
D. 73
Answer» B. 42
52.

The input impedance of a quarter wave line 50 ohm and load impedance of20 ohm is

A. 50
B. 20
C. 1000
D. 125
Answer» E.
53.

The transmission coefficient is given by 0.65. Find the return loss of thewave.

A. 9.11
B. 1.99
C. 1.19
D. 9.91
Answer» B. 1.99
54.

The total charge of a surface with densities 1,2,…,10 is

A. 11
B. 33
C. 55
D. 77
Answer» D. 77
55.

at R = 4m and σ = -3 at R = 5m. Find the flux density at R = 6m.

A. 17/6
B. -17/6
C. 13/6
D. -13/6
Answer» E.
56.

Find the load impedance in a quarter line transformer with characteristicimpedance of 75 ohm and input impedance of 200 ohm.

A. 28.125
B. 12.285
C. 52.185
D. 85.128
Answer» B. 12.285
57.

πεh).aN. State True/False.

A. true
B. false
Answer» B. false
58.

The current reflection coefficient of a line with voltage reflection coefficient of0.65 is given by

A. 0
B. 0.65
C. -0.65
D. 0.35
Answer» D. 0.35
59.

The time constant of an R-C circuit is defined as the time during which capacitorcharging voltage actually rises to percent of its value.

A. 37, initial
B. 63.2, initial
C. 63.2, final
D. 37, final
Answer» D. 37, final
60.

For an infinite transmission line, the characteristic impedance is given by 50ohm. Find the input impedance.

A. 25
B. 100
C. 2500
D. 50
Answer» E.
61.

Find the characteristic impedance of a quarter wave with input and loadimpedances given by 50 and 25 respectively.

A. 50
B. 25
C. 75
D. 35.35
Answer» E.
62.

Electric displacement is a            quantity.

A. scalar
B. vector
C. both of the above
D. none of the above
Answer» C. both of the above
63.

Those magnetic materials are best suited for making armature and transformer coreswhich have permeability and hystersis loss.

A. high, high
B. low, high
C. high, low
D. low, low
Answer» D. low, low
64.

According to Faraday’s law, EMF stands for

A. electromagnetic field
B. electromagnetic force
C. electromagnetic friction
D. electromotive force
Answer» E.
65.

The electromagnet has 50 turns and a current of 1A flows through the coil. If the lengthof the magnet circuit is 200 mm, what is the magnetic field strength ?

A. 2500 at/m
B. 250 at/m
C. 25 at/m
D. 2.5 at/m
Answer» C. 25 at/m
66.

Find the divergence of the vector F= xe-x i + y j – xz k

A. (1 – x)(1 + e-x)
B. (x – 1)(1 + e-x)
C. (1 – x)(1 – e)
D. (x – 1)(1 – e)
Answer» B. (x – 1)(1 + e-x)
67.

Find the receiving impedance of a transmission line having a voltage of 24Vand a conduction current of 1.2A is

A. 25.2
B. 22.8
C. 28.8
D. 20
Answer» E.
68.

The input impedance of a half wave transmission line with a load impedanceof 12.5 ohm is

A. 25
B. 50
C. 6.25
D. 12.5
Answer» E.
69.

The power of a wave of with voltage of 140V and a characteristic impedance of 50 ohmis

A. 1.96
B. 19.6
C. 196
D. 19600
Answer» D. 19600
70.

Given the vector potential is 16 – 12sin y j. Find the field intensity at the origin.

A. 28
B. 16
C. 12
D. 4
Answer» D. 4
71.

What is the potential difference between 10sinθcosφ/r2 at A(1,30,20) and B(4,90,60)?

A. 2.386
B. 3.386
C. 4.386
D. 5.386
Answer» D. 5.386
72.

When the ratio of load voltage to input voltage is 5, the ratio of thecharacteristic impedance to the input impedance is

A. 1/5
B. 5
C. 10
D. 25
Answer» C. 10
73.

at R = 4m and σ =-3 at R = 5m. Find the flux density at R = 4.5m.

A. 4/4.5
B. 3/4.5
C. 2/4.5
D. 1/4.5
Answer» D. 1/4.5
74.

The transmission coefficient in a wave travelling through two media havingintrinsic impedances of 5.5 and 1.33 is

A. 0.389
B. 0.55
C. 0.133
D. 0.42
Answer» B. 0.55
75.

The reflection coefficient of a transmission line having characteristic and loadimpedances as 50 and 30 ohm respectively is

A. 1/4
B. 1/8
C. 1/2
D. 3/4
Answer» B. 1/8
76.

The incident wave amplitude is 24 units. Find the reflected wave amplitude ifthe reflection coefficient is 0.6.

A. 14.4
B. 16.6
C. 13.3
D. 11.1
Answer» B. 16.6
77.

Find the potential of the function V = 60cos θ/r at the point P(3, 60, 25).

A. 20
B. 10
C. 30
D. 60
Answer» C. 30
78.

When a transmission line has a load impedance same as that of thecharacteristic impedance, the line is said to be

A. parallel
B. perpendicular
C. polarized
D. matched
Answer» E.
79.

The power of the electromagnetic wave with electric and magnetic fieldintensities given by 12 and 15 respectively is

A. 180
B. 90
C. 45
D. 120
Answer» C. 45
80.

Given that R = 20 ohm, L = 40 mH, C = 40 μF, G = 0.02 mho. Find whetherthe line is distortionless or not.

A. distorted line
B. distortionless line
C. all of the mentioned
D. none of the mentioned
Answer» C. all of the mentioned
81.

The centre of the point having a normalised resistance of 1.2 ohm andreactance of 1.5 ohm is

A. (0.54,0)
B. (0.45,0)
C. (0.36,0)
D. (0.78,0)
Answer» B. (0.45,0)
82.

The transmission coefficient in a wave travelling through two media havingpermittivities 4 and 1 is

A. 1/4
B. 3/2
C. 3/4
D. 2/3
Answer» E.
83.

A square cross-sectional magnet has a pole strength of 1 x 10 Wb and cross sectionalarea of 20 mm x 20 mm. What is the strength at a distance of 100 mm from the unit pole in air ?

A. 63.38 n/wb
B. 633.8 n/wb
C. 6338 n/wb
D. 63380 n/wb
Answer» D. 63380 n/wb
84.

kV. Find „a‟.

A. 1m
B. 1cm
C. 10cm
D. 1mm
Answer» E.
85.

When the length of the transmission line is same as that of the wavelength,then which condition holds good?

A. zin = zo
B. z = zo
C. zl = zo
D. zin = zl
Answer» E.
86.

The characteristic impedance of a transmission line with impedance andadmittance of 16 and 9 respectively is

A. 25
B. 1.33
C. 7
D. 0.75
Answer» C. 7
87.

The reflection coefficient of a wave travelling through two media havingpermittivities 4 and 9 respectively is

A. 0
B. 0.5
C. 0.25
D. 0.2
Answer» E.
88.

A 200 turn coil having an axial length of 30 mm and a radius of 10 mm is pivoted in a magnetic field having a flux density of 0.8 T. If the coil carries a current of 0.5 A, the torque acting on the coil will be

A. 0.48 N-m
B. 4.8 N-m
C. 0.0048 N-m
D. 0.048 N-m
Answer» E.
89.

The simplest kind of capacitor is ________

A. ceramic capacitor
B. electrolyte capacitor
C. tuning capacitor
D. paper capacitor
Answer» E.
90.

Paper capacitor is a type of _________

A. fixed capacitor
B. variable capacitor
C. either fixed or variable depending on its usage
D. neither fixed nor variable
Answer» B. variable capacitor
91.

Displacement current depends on ___________

A. moving charges
B. change in time
C. both moving charges and change in time
D. neither moving charges nor change in time
Answer» C. both moving charges and change in time
92.

In a variable capacitor, capacitance can be varied by ______

A. turning the rotatable plates in or out
B. sliding the rotatable plates
C. changing the plates
D. changing the material of plates
Answer» B. sliding the rotatable plates
93.

Leakage in capacitors is primarily caused by _________

A. transistors
B. resistors
C. inductors
D. dc motors
Answer» B. resistors
94.

The flow of electrons in dielectric is due to _________

A. conduction
B. potential difference
C. breakdown
D. resistance
Answer» D. resistance
95.

m, calculate the dielectric strength.

A. 2mv/m
B. 4mv/m
C. 6mv/m
D. 8mv/m
Answer» B. 4mv/m
96.

The unit for dielectric strength is ____________

A. v/m2
B. mv/m2
C. mv/m
D. vm
Answer» D. vm
97.

kV. Find „a‟.

A. 10mm
B. 100mm
C. 1000m
D. 1000cm
Answer» E.
98.

kV.

A. 350n
B. 0.035kn
C. 0.035n
D. 3.35kn
Answer» D. 3.35kn
99.

in air.

A. 1.41
B. 3.5
C. 2.2
D. 1.73
Answer» E.
100.

units and E = 8 units.

A. 1.77
B. 2.25
C. 36
D. 144
Answer» D. 144