9294 + Mcqs in Electronics and Communication Engineering Page 113 McqOptions

5601.	The phase velocity v in a transmission line is
A.	LC
B.	<span class="root">C/L</span>
C.	<span class="root">L/C</span>
D.	1/
E.	<span class="root">LC</span>
Answer» E. <span class="root">LC</span>

Discussion

5602.	In a series RLC high Q circuit the current peaks at a frequency.
A.	equal to the resonant frequency
B.	greater than the resonant frequency
C.	less than the resonant frequency
D.	none
Answer» B. greater than the resonant frequency

Discussion

5603.	A circuit is fed by two sources of different frequency and magnitudes 100 0 V and 50 30 V. The current in a particular branch is 10 20 A. If the magnitudes of the sources are changed to 200 0 V and 100 0 V, the current in that branch should be
A.	20 20 A
B.	10 20 A
C.	14.14 20 A
D.	10 - 20 A
Answer» B. 10 20 A

Discussion

5604.	In gases the flow of current is due to
A.	positive ions only
B.	electrons only
C.	electrons, positive ions and negative ions
D.	electrons and positive ions
Answer» D. electrons and positive ions

Discussion

5605.	In ZRC (s) = 0 at s = , the last element in first Cauer form is
A.	R
B.	C
C.	R and C in series
D.	R and C in parallel
Answer» C. R and C in series

Discussion

5606.	In most electric irons, the thermister used for controlling temperature is
A.	vapour-filled bulb
B.	high-expansion steel rod
C.	bimetallic strip
D.	thermopile
Answer» D. thermopile

Discussion

5607.	In low pass filter of figure R0 = 1 &ohm; and cut off frequency is 1 rad/sec. The values of L and C are
A.	1 H and 2 F
B.	1 H and 1 F
C.	2 H and 1 F
D.	1 H and 2 F
Answer» E.

Discussion

5608.	A second order system will have
A.	all resistances
B.	resistances and inductances
C.	resistances, inductance and capacitances
D.	either (b) or (c)
Answer» C. resistances, inductance and capacitances

Discussion

5609.	L/C has the dimension of
A.	time
B.	capacitance
C.	inductance
D.	resistance
Answer» E.

Discussion

5610.	In metals, the flow of current is due to
A.	electrons
B.	ions
C.	holes
D.	electrons and ions
Answer» B. ions

Discussion

5611.	In drawing phasor diagrams, RMS values are used.
A.	True
B.	False
Answer» B. False

Discussion

5612.	RMS value is always higher than average value.
A.	True
B.	False
Answer» B. False

Discussion

5613.	When R and L are connected in parallel, R > \|Z\|.
A.	True
B.	False
Answer» B. False

Discussion

5614.	To neglect a current source the terminals across the source are
A.	replaced by some resistance
B.	replaced by capacitance
C.	open-circuited
D.	short-circuited
Answer» D. short-circuited

Discussion

5615.	The network shown in figure is
A.	reciprocal
B.	reciprocal and symmetrical
C.	non-reciprocal
D.	unsymmetrical
Answer» D. unsymmetrical

Discussion

5616.	The two conductors of a single phase transmission line suspended in air carry currents in opposite directions. The force per unit length on each conductor varies
A.	directly as the current in either conductor
B.	directly as the distance between the two conductors
C.	directly as the square of the current in either conductor
D.	inversely as the square of the distance between the two conductors
Answer» D. inversely as the square of the distance between the two conductors

Discussion

5617.	The series element for a prototype high pass filter is
A.	resistive
B.	inductive
C.	capacitive
D.	combination of L and C
Answer» D. combination of L and C

Discussion

5618.	The scale factor for half wave and full wave rectifier is __________ respectively.
A.	1.11, 1.414
B.	1.11, 1.57
C.	1.57, 1.11
D.	1.414, 1.11
Answer» E.

Discussion

5619.	The polarities of the magnetised iron rod of are
A.	A is N, B is S and C is neutral
B.	A is N, B is S and C is S
C.	A is N, B is N and C is S
D.	A is S, N is S and C is N
Answer» D. A is S, N is S and C is N

Discussion

5620.	Nichrome is commonly used for
A.	lamp filaments
B.	transformer winding
C.	heater coils
D.	battery connections
Answer» D. battery connections

Discussion

5621.	Thevenin's equivalent circuit
A.	can be drawn only in time domain
B.	can be drawn only in frequency domain
C.	can be drawn both in time and frequency domain
D.	can be drawn in frequency domain with some restrictions
Answer» D. can be drawn in frequency domain with some restrictions

Discussion

5622.	A series RC circuit has fixed R and C and variable f. The current locus will lie in the first quadrant.
A.	True
B.	False
Answer» B. False

Discussion

5623.	The time constant of a series RL circuit is
A.	LR
B.	L/R
C.	R/L
D.	<i>e</i>
E.	<sup>-R/L</sup>
Answer» D. <i>e</i>

Discussion

5624.	Ideally an attenuator pad should not change
A.	voltage level
B.	impedance level
C.	power level
D.	voltage, power or impedance level
Answer» C. power level

Discussion

5625.	The peak factor is the ratio of
A.	peak and rms values
B.	peak and average values
C.	rms and average values
D.	none of the above
Answer» B. peak and average values

Discussion

5626.	In attenuation band, is an odd multiple of p.
A.	True
B.	False
Answer» B. False

Discussion

5627.	Which of the following is correct? The circuit shown in the figure. is reciprocal but not symmetricalis not reciprocal but symmetricalboth reciprocal and symmetricalneither reciprocal nor symmetrical
A.	1, 2 and 3
B.	2, 3 and 4
C.	1, 3 and 4
D.	1, 2 and 4
Answer» B. 2, 3 and 4

Discussion

5628.	For the circuit of figure, the time constant is
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/125-733-2.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/125-733-3.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/125-733-4.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/125-733-5.png">
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/125-733-3.png">

Discussion

5629.	The ratio of active power to apparent power is known as __________ factor.
A.	power
B.	load
C.	form
D.	demand
Answer» B. load

Discussion

5630.	A pole zero plot of a filter is shown in figure. It is
A.	low pass filter
B.	high pass filter
C.	band pass filter
D.	all pass filter
Answer» E.

Discussion

5631.	Assertion (A): In a parallel circuit having two branches, each branch current may be more than source current.Reason (R): Calculations in ac circuits use rules of complex algebra.
A.	Both A and R are true and R is correct explanation of A
B.	Both A and R are true and R is not the correct explanation of A
C.	A is true but R is false
D.	A is false but R is true
Answer» C. A is true but R is false

Discussion

5632.	Which one of the following parameters does not exist for the two port network shown in the given figure?
A.	ABCD
B.	<i>y</i>
C.	<i>h</i>
D.	<i>z</i>
Answer» E.

Discussion

5633.	Two RLC series circuit has same damping ratio. Circuit 1 has higher natural frequency as compared to circuit 2. Then
A.	transients in circuit 2 will decay faster
B.	transients in circuit 1 will decay faster
C.	transients in both circuits will decay at the same rate
D.	transients in any one may decay faster than in the other
Answer» C. transients in both circuits will decay at the same rate

Discussion

5634.	The minimum permissible size of aluminium cable for lighting circuit is
A.	1.2 sq. mm
B.	1.5 sq. mm
C.	2.2 sq. mm
D.	3.5 sq. mm
Answer» C. 2.2 sq. mm

Discussion

5635.	Current density J, conductivity and electric field E in a conductor are related as
A.	J = E
B.	= JE
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/106-431-1.png">
D.	J = E
E.	<sup>2</sup>
Answer» B. = JE

Discussion

5636.	Consider the following statement : If a network has an impedance of (1 - j) as a specific frequency, the circuit would consist of series R and CR and LR, L and C Which of the statement are correct?
A.	1 and 2
B.	1 and 3
C.	1, 2 and 3
D.	2 and 3
Answer» C. 1, 2 and 3

Discussion

5637.	A dc voltage source is connected across a series RLC circuit, Under steady state conditions, the applied dc voltage drops entirely across the
A.	R only
B.	C only
C.	L only
D.	R and L
Answer» C. L only

Discussion

5638.	The inductance of a coil can be increased by
A.	choosing core material having high relative permeability
B.	decreasing diameter of the former
C.	decreasing the number of turns
D.	increasing core length
Answer» B. decreasing diameter of the former

Discussion

5639.	Maximum power transfer theorem is applicable to circuits with one source only.
A.	True
B.	False
Answer» B. False

Discussion

5640.	Laplace transform method enables us to find the response in
A.	steady state
B.	transient state
C.	both steady and transient state
D.	transient state provided forcing functions do not exist
Answer» D. transient state provided forcing functions do not exist

Discussion

5641.	The model of a system
A.	is unique
B.	depends on desired degree of accuracy
C.	depends on the type of analysis
D.	both (b) and (c)
Answer» C. depends on the type of analysis

Discussion

5642.	Q of a coil increases with Q increasing frequencyvaries linearly with frequencyincrease with increasing frequency because R increases at high frequencydecrease after the peak frequency because R increases at H.F. the correct statements are
A.	A, B
B.	C, D
C.	A, C
D.	B, D
Answer» C. A, C

Discussion

5643.	For node 2 in figure, KCL equation is
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/107-449-1.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/107-449-2.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/107-449-3.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/107-449-4.png">
Answer» C. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/107-449-3.png">

Discussion

5644.	Which one of the following is positive real function?
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/120-670-1.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/120-670-2.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/121-670-3.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/121-670-4.png">
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/120-670-2.png">

Discussion

5645.	The dynamic impedance of an R-L and C parallel circuit at resonance is __________ ohm.
A.	R/LC
B.	C/LR
C.	LC/R
D.	L/CR
Answer» E.

Discussion

5646.	The hot resistance of a tungsten lame is about 12 times its cold resistance. Accordingly, the cold resistance of a 60 &ohm;, 120 V lamp is about __________ ohm.
A.	5
B.	240
C.	2
D.	2880
Answer» D. 2880

Discussion

5647.	The response of a function is decided by
A.	the location of its zeros
B.	the location of its poles
C.	both (a) and (b)
D.	none of the above
Answer» D. none of the above

Discussion

5648.	h parameters are used in transistor analysis.
A.	True
B.	False
Answer» B. False

Discussion

5649.	At a temperature of 7 K, lead is a superconductor.
A.	True
B.	False
Answer» B. False

Discussion

5650.	Which of the under-given graphs shown in figure gives variation in resistance of a copper conductor with temperature?
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/127-764-1.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/127-764-2.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/127-764-3.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/127-764-4.png">
Answer» C. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/127-764-3.png">

Discussion

Explore topic-wise MCQs in Engineering.

The phase velocity v in a transmission line is

In a series RLC high Q circuit the current peaks at a frequency.

A circuit is fed by two sources of different frequency and magnitudes 100 0 V and 50 30 V. The current in a particular branch is 10 20 A. If the magnitudes of the sources are changed to 200 0 V and 100 0 V, the current in that branch should be

In gases the flow of current is due to

In ZRC (s) = 0 at s = , the last element in first Cauer form is

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A second order system will have

L/C has the dimension of

In metals, the flow of current is due to

In drawing phasor diagrams, RMS values are used.

RMS value is always higher than average value.

When R and L are connected in parallel, R &gt; |Z|.

To neglect a current source the terminals across the source are

The network shown in figure is

The two conductors of a single phase transmission line suspended in air carry currents in opposite directions. The force per unit length on each conductor varies

The series element for a prototype high pass filter is

The scale factor for half wave and full wave rectifier is __________ respectively.

The polarities of the magnetised iron rod of are

Nichrome is commonly used for

Thevenin's equivalent circuit

A series RC circuit has fixed R and C and variable f. The current locus will lie in the first quadrant.

The time constant of a series RL circuit is

Ideally an attenuator pad should not change

The peak factor is the ratio of

In attenuation band, is an odd multiple of p.

Which of the following is correct? The circuit shown in the figure. is reciprocal but not symmetricalis not reciprocal but symmetricalboth reciprocal and symmetricalneither reciprocal nor symmetrical

For the circuit of figure, the time constant is

The ratio of active power to apparent power is known as __________ factor.

A pole zero plot of a filter is shown in figure. It is

Assertion (A): In a parallel circuit having two branches, each branch current may be more than source current.Reason (R): Calculations in ac circuits use rules of complex algebra.

Which one of the following parameters does not exist for the two port network shown in the given figure?

Two RLC series circuit has same damping ratio. Circuit 1 has higher natural frequency as compared to circuit 2. Then

The minimum permissible size of aluminium cable for lighting circuit is

Current density J, conductivity and electric field E in a conductor are related as

Consider the following statement : If a network has an impedance of (1 - j) as a specific frequency, the circuit would consist of series R and CR and LR, L and C Which of the statement are correct?

A dc voltage source is connected across a series RLC circuit, Under steady state conditions, the applied dc voltage drops entirely across the

The inductance of a coil can be increased by

Maximum power transfer theorem is applicable to circuits with one source only.

Laplace transform method enables us to find the response in

The model of a system

Q of a coil increases with Q increasing frequencyvaries linearly with frequencyincrease with increasing frequency because R increases at high frequencydecrease after the peak frequency because R increases at H.F. the correct statements are

For node 2 in figure, KCL equation is

Which one of the following is positive real function?

The dynamic impedance of an R-L and C parallel circuit at resonance is __________ ohm.

The hot resistance of a tungsten lame is about 12 times its cold resistance. Accordingly, the cold resistance of a 60 &amp;ohm;, 120 V lamp is about __________ ohm.

The response of a function is decided by

h parameters are used in transistor analysis.

At a temperature of 7 K, lead is a superconductor.

Which of the under-given graphs shown in figure gives variation in resistance of a copper conductor with temperature?

In low pass filter of figure R0 = 1 &ohm; and cut off frequency is 1 rad/sec. The values of L and C are

When R and L are connected in parallel, R > |Z|.

The hot resistance of a tungsten lame is about 12 times its cold resistance. Accordingly, the cold resistance of a 60 &ohm;, 120 V lamp is about __________ ohm.