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.

201.

Calculate the transmission coefficient, when the incident and transmitted amplitudes are 10 and 7 respectively.

A. 17
B. 3
C. 10/7
D. 0.7
Answer» E.
202.

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

A. 0
B. 0.5
C. 0.25
D. 0.2
Answer» E.
203.

Find the reflection coefficient of the wave passing through two media having intrinsic impedances of 4 and 9 respectively.

A. 0.5
B. 1
C. 0.38
D. 0.1
Answer» D. 0.1
204.

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

A. 14.4
B. 16.6
C. 13.3
D. 11.1
Answer» B. 16.6
205.

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

A. 1/5
B. 5
C. 10
D. 25
Answer» C. 10
206.

The reflection coefficient lies in the range of

A. 0 < Ï„ < 1
B. -1 < Ï„ < 1
C. 1 < τ < ∞
D. 0 < τ < ∞
Answer» B. -1 < Ï„ < 1
207.

The input impedance of a quarter wave line 50 ohm and load impedance of 20 ohm is

A. 50
B. 20
C. 1000
D. 125
Answer» E.
208.

The reflection coefficient of a wave with transmission coefficient 0.35 is

A. 1.35
B. 0.65
C. 0.35
D. 0.7
Answer» C. 0.35
209.

The characteristic impedance of a quarter wave transformer with load and input impedances given by 30 and 75 respectively is

A. 47.43
B. 37.34
C. 73.23
D. 67.45
Answer» B. 37.34
210.

The quarter wave transformer can be considered as a

A. impedance inverter
B. impedance doubler
C. impedance tripler
D. impedance quadrupler
Answer» B. impedance doubler
211.

The purpose of the transmission line equation is to

A. find primary parameters
B. find secondary parameters
C. find the reflection cofficient
D. impedance matching
Answer» E.
212.

The reflection coefficient of a perfectly matched transmission line is

A. 1
B. -1
C. ∞
Answer» D.
213.

Which transmission line is called as one to one transformer?

A. l = λ
B. l = λ/2
C. l = λ/4
D. l = λ/8
Answer» C. l = λ/4
214.

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

A. 50
B. 25
C. 75
D. 35.35
Answer» E.
215.

The condition for a quarter wave transformer is

A. zo2 = zin zl
B. zo = zin zl
C. zl2 = zin zo
D. zo = zin
Answer» B. zo = zin zl
216.

Find the load impedance in a quarter line transformer with characteristic impedance 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
217.

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

A. 25
B. 50
C. 6.25
D. 12.5
Answer» E.
218.

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.
219.

The best transmission length for effective transmission of power is

A. l = λ/4
B. l = λ/8
C. l = λ/2
D. l = ∞
Answer» C. l = λ/2
220.

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

A. 25
B. 100
C. 2500
D. 50
Answer» E.
221.

Which of the following parameters does not exist in the transmission line equation?

A. r
B. zo
C. zl
D. propagation constant
Answer» B. zo
222.

The velocity of wave in the air medium is

A. 1 x 108
B. 1.5 x 108
C. 3 x 108
D. 1 x 109
Answer» D. 1 x 109
223.

The propagation constant of a wave with attenuation and phase constant given by 2 and 3 respectively is

A. 2 – 3j
B. 3 – 2j
C. 2 + 3j
D. 3 + 2j
Answer» D. 3 + 2j
224.

The unit of attenuation constant is

A. decibel
B. bel
C. neper
D. no unit
Answer» D. no unit
225.

Identify the secondary parameter from the options given below.

A. resistance
B. conductance
C. phase constant
D. capacitance
Answer» D. capacitance
226.

The wavelength of a line with a phase constant of 6.28 units is

A. 2
B. 1
C. 0.5
D. 3.14
Answer» C. 0.5
227.

The electrical length in a transmission line refers to the

A. product of attenuation constant and length
B. ratio of attenuation constant and length
C. product of phase constant and length
D. ratio of phase constant and length
Answer» B. ratio of attenuation constant and length
228.

The phase constant of a wave with a wavelength of 2 units is given by

A. 2
B. 3.14
C. 6.28
D. 1
Answer» C. 6.28
229.

The velocity and phase constant relation is given by

A. v = ω/β
B. v = ωβ
C. v = β/ω
D. vωβ = 1
Answer» B. v = ωβ
230.

The frequency of a wave travelling in a transmission line with velocity 4 x 108 and wavelength 3 units is

A. 0.75 ghz
B. 0.133 ghz
C. 7.5 ghz
D. 1.33 ghz
Answer» C. 7.5 ghz
231.

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

A. parallel
B. perpendicular
C. polarized
D. matched
Answer» E.
232.

The wavelength of a wave with a frequency of 6 GHz in air is

A. 50
B. 5
C. 0.5
D. 0.05
Answer» E.
233.

Find the characteristic impedance expression in terms of the inductance and capacitance parameters.

A. zo = √(lc)
B. zo = lc
C. zo = √(l/c)
D. zo = l/c
Answer» D. zo = l/c
234.

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

A. 25
B. 1.33
C. 7
D. 0.75
Answer» C. 7
235.

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

A. 25.2
B. 22.8
C. 28.8
D. 20
Answer» E.
236.

The primary parameter that is associated with the electric charges is

A. g
B. r
C. c
D. l
Answer» D. l
237.

The primary parameter that is associated with the magnetic flux linkage is

A. r
B. l
C. c
D. g
Answer» C. c
238.

Which primary parameter is uniformly distributed along the length of the conductor?

A. g
B. c
C. l
D. r
Answer» E.
239.

The networks in which the R, L, C parameters are individually concentrated or lumped at discrete points in the circuit are called

A. lumped
B. distributed
C. parallel
D. paired
Answer» B. distributed
240.

The lines having R, L, C distributed along the circuit are called

A. lumped
B. distributed
C. parallel
D. paired
Answer» C. parallel
241.

Which of the following parameters is not a primary parameter?

A. resistance
B. attenuation constant
C. capacitance
D. conductance
Answer» C. capacitance
242.

A coil is wound on iron core which carries current I. The self-induced voltage in the coil is not affected by

A. variation in coil current
B. variation in voltage to the coil
C. change of number of turns of coil
D. the resistance of magnetic path
Answer» C. change of number of turns of coil
243.

A crack in the magnetic path of an inductor will result in

A. unchanged inductance
B. increased inductance
C. zero inductance
D. reduced inductance
Answer» E.
244.

Which circuit element(s) will oppose the change in circuit current ?

A. resistance only
B. inductance only
C. capacitance only
D. inductance and capacitance
Answer» C. capacitance only
245.

Current changing from 8 A to 12 A in one second induced 20 volts in a coil. The value of inductance is

A. 5 mh
B. 10 mh
C. 5 h
D. 10 h
Answer» D. 10 h
246.

Two 300 uH coils in series without mutual coupling have a total inductance of

A. 300 uh
B. 600 uh
C. 150 uh
D. 75 uh
Answer» C. 150 uh
247.

A coil induces 350 mV when the current changes at the rate of 1 A/s. The value of inductance is

A. 3500 mh
B. 350 mh
C. 250 mh
D. 150 mh
Answer» C. 250 mh
248.

Which of the fpllowing inductor will have the least eddy current losses ?

A. air core
B. laminated iron core
C. iron core
D. powdered iron core
Answer» B. laminated iron core
249.

An average voltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is

A. 20 wb
B. 2 wb
C. 0.2 wb
D. 0.02 wb
Answer» E.
250.

The co-efficient of coupling between two air core coils depends on

A. self-inductance of two coils only
B. mutual inductance between two coils only
C. mutual inductance and self inductance of two coils
D. none of the above
Answer» D. none of the above