Explore topic-wise MCQs in Electrical Engineering.

This section includes 247 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.

The modes of propagation supported by a rectangular wave guide is:

A. tm, tem, te modes
B. tm, te
C. tm, tem
D. te, tem
Answer» C. tm, tem
202.

For TE1â‚’ mode, if the waveguide is filled with air and the broader dimension of the waveguide is 2 cm, then the cutoff frequency is:

A. 5 mhz
B. 7.5 mhz
C. 7.5 ghz
D. 5 ghz
Answer» D. 5 ghz
203.

The major advantage of double stub tuning is:

A. it uses 2 tuning stubs in fixed positions
B. it involves 2 stubs
C. length of the stub is variable
D. none of the mentioned
Answer» B. it involves 2 stubs
204.

In a double stub tuner circuit, the load is of _______ length from the first stub.

A. fixed length
B. arbitrary length
C. depends on the load impedance to be matched
D. depends on the characteristic impedance of the transmission line
Answer» C. depends on the load impedance to be matched
205.

The major disadvantage of single stub tuning is:

A. it requires a variable length of line between the load and the stub
B. it involves 2 variable parameters
C. complex calculation
D. none of the mentioned
Answer» B. it involves 2 variable parameters
206.

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

A. 1/4
B. 1/8
C. 1/2
D. 3/4
Answer» B. 1/8
207.

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.
208.

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.
209.

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
210.

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

A. g
B. c
C. l
D. r
Answer» E.
211.

The lowest mode of TE mode propagation in a circular waveguide is:

A. te10 mode
B. te00 mode
C. te01 mode
D. te11 mode
Answer» D. te11 mode
212.

When a λ/4 transmission line is used for impedance matching, then which of the following is valid?

A. standing waves are present on the λ/4 transmission line
B. no standing waves on the λ/4 transmission line
C. standing waves are not present both on the feed line and the matching λ/4 line
D. standing waves are present on both the feed line and the matching λ/4 line
Answer» B. no standing waves on the λ/4 transmission line
213.

If there is no standing wave on a transmission line, then the value of SWR is:

A. 1
B. 0
C. infinity
D. insufficient data
Answer» B. 0
214.

Expression for the characteristic impedance of a transmission line(λ/4) used for impedance matching is:

A. z1=√(zₒr)l
B. z1=√(zₒ/r)l
C. z1=√(zₒ+r)l
D. none of the mentioned
Answer» B. z1=√(zâ‚’/r)l
215.

maintain at safe limit.

A. average current
B. average voltage
C. average bias voltage
D. average resistance
Answer» B. average voltage
216.

an IMPATT diode, it results in:

A. avalanche multiplication
B. break down of depletion region
C. high reverse saturation current
D. none of the mentioned
Answer» B. break down of depletion region
217.

The mode of operation in which the Gunn diode is not stable is:

A. gunn oscillation mode
B. limited space charge accumulation mode
C. stable amplification mode
D. bias circuit oscillation mode
Answer» B. limited space charge accumulation mode
218.

GaAs is used in fabricating Gunn diode. Gunn diode is:

A. bulk device
B. sliced device
C. made of different type of semiconductor layers
D. none of the mentioned
Answer» B. sliced device
219.

GaAs is used in the fabrication of GUNN diodes because:

A. gaas is cost effective
B. it less temperature sensitive
C. it has low conduction band electrons
D. less forbidden energy gap
Answer» E.
220.

The material out of which PIN diode is made is:

A. silicon
B. germanium
C. gaas
D. none of the mentioned
Answer» B. germanium
221.

A major disadvantage of klystron amplifier is:

A. low power gain
B. low bandwidth
C. high source power
D. design complexity
Answer» C. high source power
222.

The phase and group velocities does not depend on which of the following?

A. frequency
B. wavelength
C. phase constant
D. attenuation constant
Answer» E.
223.

Which of the following parameter is non zero for a lossless line?

A. attenuation
B. resistance
C. conductance
D. phase constant
Answer» E.
224.

reflector electrode after the cavity.

A. backward wave oscillator
B. reflex klystron
C. travelling wave tube
D. magnetrons
Answer» C. travelling wave tube
225.

amplifier.

A. linear beam
B. crossed field
C. parallel field
D. none of the mentioned
Answer» B. crossed field
226.

The propagation constant for a lossless transmission line will be

A. real
B. complex
C. real and equal to phase constant
D. complex and equal to phase constant
Answer» E.
227.

In transverse electric waves, which of the following is true?

A. e is parallel to h
B. e is parallel to wave direction
C. e is transverse to wave direction
D. h is transverse to wave direction
Answer» D. h is transverse to wave direction
228.

The dominant mode in rectangular waveguide is

A. te01
B. te10
C. tm01
D. tm10
Answer» C. tm01
229.

The cut off frequency for a waveguide to operate is

A. 3 mhz
B. 3 ghz
C. 6 mhz
D. 6 ghz
Answer» E.
230.

In rectangular waveguides, the dimensions a and b represent the

A. broad wall dimensions
B. broad wall and side wall dimension respectively
C. side wall and broad wall dimension respectively
D. side wall dimensions
Answer» C. side wall and broad wall dimension respectively
231.

range of

A. hz
B. khz
C. mhz
D. ghz
Answer» E.
232.

For the matched line, the parameters S12 and S21 are

A. 1
B. 0
C. -1
D. ∞
Answer» C. -1
233.

The waveguides are materials with characteristics of

A. low bulk resistivity
B. high bulk resistivity
C. high conductivity
D. low conductivity
Answer» B. high bulk resistivity
234.

The scattering parameters are used to indicate the

A. permittivity and permeability
B. electric and magnetic field intensities
C. reflection and transmission coefficients
D. frequency and wavelength
Answer» D. frequency and wavelength
235.

The circular waveguides use which function in the frequency calculation?

A. laplace function
B. schottky function
C. bessel function
D. transfer function
Answer» D. transfer function
236.

The modes are calculated from which parameter?

A. frequency
B. wavelength
C. phase constant
D. v number
Answer» E.
237.

The dominant mode in waveguide is the mode which has

A. highest frequency
B. highest wavelength
C. lowest phase constant
D. highest attenuation
Answer» C. lowest phase constant
238.

The best stub selection for the transmission line will be

A. series open
B. series short
C. shunt open
D. shunt short
Answer» E.
239.

respectively. The standing wave ratio is

A. 2
B. 3
C. 1/2
D. 4
Answer» C. 1/2
240.

The phenomenon employed in the waveguide operation is

A. reflection
B. refraction
C. total internal reflection
D. adsorption
Answer» D. adsorption
241.

Identify the material which is not present in a transmission line setup.

A. waveguides
B. cavity resonator
C. antenna
D. oscillator
Answer» E.
242.

The characteristic impedance of a transmission line is normally chosen to be

A. 50
B. 75
C. 50 or 75
D. 100
Answer» D. 100
243.

The average power in an electromagnetic wave is given by

A. propagation constant
B. pointing vector
C. phase constant
D. attenuation constant
Answer» C. phase constant
244.

For a matched line, the input impedance will be equal to

A. load impedance
B. characteristic impedance
C. output impedance
D. zero
Answer» C. output impedance
245.

wave ratio of 2.5 is

A. 20
B. 125
C. 200
D. 75
Answer» C. 200
246.

ohm is

A. 50
B. 20
C. 1000
D. 125
Answer» E.
247.

. Which of the following parameters is not a primary parameter?

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