9294 + Mcqs in Electronics and Communication Engineering Page 52 McqOptions

2551.	Assertion (A): The impedance of a series resonant circuit is minimum at resonance.Reason (R): Resonance condition implies unity power factor condition.
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» B. Both A and R are true and R is not the correct explanation of A

Discussion

2552.	The following circuit resonates at
A.	0.5 Hz
B.	5 Hz
C.	1 rad/sec
D.	0.5 rad/sec
Answer» E.

Discussion

2553.	A steel bar needs 1200 AT to magnetise it. The voltage that must be applied to the magnetising coil of 100 turns and 10 &ohm; resistance is __________ volt.
A.	120
B.	12
C.	1200
D.	10
Answer» B. 12

Discussion

2554.	Poor power factor
A.	reduces load handling capability of electrical system
B.	results in more power losses in the electrical system
C.	overloads alternators, transformers and distribution lines
D.	all
Answer» E.

Discussion

2555.	A reactance function is always a quotient of
A.	even to odd polynomials
B.	odd to even polynomials
C.	even to odd or odd to even polynomials
D.	even to even polynomials
Answer» B. odd to even polynomials

Discussion

2556.	The Z parameter of the following T-network is
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/131-827-2.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/131-827-3.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/131-827-4.png">
D.	not possible
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/131-827-3.png">

Discussion

2557.	In figure the effective resistance faced by voltage source is
A.	1 &ohm;
B.	2 &ohm;
C.	3 &ohm;
D.	3.3 &ohm;
Answer» C. 3 &ohm;

Discussion

2558.	For a series circuit of R and variable XL the admittance locus is
A.	a semicircle in first quadrant
B.	a semicircle in fourth quadrant
C.	a straight line in first quadrant
D.	a straight line in fourth quadrant
Answer» C. a straight line in first quadrant

Discussion

2559.	Assertion (A): In drawing an electric circuit analogous to a mechanical circuit, spring is replaced by capacitance.Reason (R): The behaviour of a spring and capacitor are similar.
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» B. Both A and R are true and R is not the correct explanation of A

Discussion

2560.	In ZRC (s) = constant at s = 0, the last element in first Foster cauer realization is
A.	R
B.	C
C.	R and C in series
D.	R and C in parallel
Answer» B. C

Discussion

2561.	Norton's equivalent circuit
A.	is same as Thevenin's circuit
B.	has no relation with Thevenin's circuit
C.	is dual of Thevenin's circuit
D.	is reciprocal of Thevenin's circuit
Answer» D. is reciprocal of Thevenin's circuit

Discussion

2562.	A 3 phase balanced supply feeds 3 phase unbalanced load. Power supplied to the load can be measured by using 2 wattmeterone wattmeter3 wattmeter Which of the above statements is correct?
A.	1 and 2
B.	1 and 3
C.	2 and 3
D.	3 alone
Answer» C. 2 and 3

Discussion

2563.	In the circuit shown in figure, for different values of R, the values of V and I are given. Other elements remaining the same. when R = , V = 5 volt R = 0, I = 2.5 AR = 3 &ohm;, the value of V is given by
A.	1 V
B.	2 V
C.	3 V
D.	5 V
Answer» D. 5 V

Discussion

2564.	In figure, E = 1 V (rms value). The average power is 250 mW. Then phase angle between E and I is
A.	90
B.	60
C.	45
D.	30
Answer» C. 45

Discussion

2565.	A current increasing at the rate of 1 A/s is passed through 1 F capacitor. At t = 0, i = 0. The charge stored after 1 second is
A.	0.5 C
B.	1 C
C.	2 C
D.	4 C
Answer» D. 4 C

Discussion

2566.	In figure, the effective resistance across AB is
A.	R
B.	R - 1
C.	R/2
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/118-638-2.png">
Answer» D. <img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/118-638-2.png">

Discussion

2567.	For the ladder network of figure, open circuit driving point impedance at port 1 =
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/98-276-2.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/98-276-3.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/98-276-4.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/98-276-5.png">
Answer» E.

Discussion

2568.	In the circuit of figure the current through 3 &ohm; resistance at t = 0+ is
A.	4 A
B.	2.5 A
C.	3.1 A
D.	0
Answer» E.

Discussion

2569.	For a high pass filter, = p in attenuation band.
A.	True
B.	False
Answer» C.

Discussion

2570.	The electrochemical equivalent of a material
A.	depends on its valency
B.	depends on its atomic weight
C.	depends on its valency and atomic weight
D.	depends on the degree of hardness of the material
Answer» D. depends on the degree of hardness of the material

Discussion

2571.	The time constant of the capacitance circuit is defined as the time during which voltage
A.	falls to 36.8% of its final steady value
B.	rises to 38.6% of its final steady value
C.	rises to 63.2% of its final steady value.
D.	none of the above.
Answer» D. none of the above.

Discussion

2572.	When a current flows through a coil of insulated wire, the coil shows the properties of a magnet.
A.	True
B.	False
Answer» B. False

Discussion

2573.	In a series RLC circuit for lower frequency power factor is __________ .
A.	leading, Lagging
B.	lagging, Leading
C.	independent of frequency
D.	same
Answer» B. lagging, Leading

Discussion

2574.	Assertion (A): Charge is dual of flux.Reason (R): Short circuit is dual of open circuit.
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

2575.	The shot circuit admittance matrix of a two port network is
A.	non-reciprocal and passive
B.	non-reciprocal and active
C.	reciprocal and passive
D.	reciprocal and active
Answer» C. reciprocal and passive

Discussion

2576.	A choke coil of resistance R and inductance L is shunted by capacitor C. The dynamic resistance is
A.	R/LC
B.	C/RL
C.	L/RC
D.	1/RLC
Answer» D. 1/RLC

Discussion

2577.	A parallel ac circuit in resonance will
A.	act like a resistor of low value
B.	have a high impedance
C.	have current in each section equal to the line current
D.	have a high voltage developed across each inductive and capacitive section
Answer» C. have current in each section equal to the line current

Discussion

2578.	Assertion (A): If Z1(s) and Z2(s) are positive real then Z1(s) + Z2(s) as well as 1/Z1(s) and 1/Z2(s) are positive real.Reason (R): The poles of a positive real function are real or occur in conjugate pairs.
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

2579.	In an unloaded transformer, the fluxes limiting the primary and secondary are 30 mWb and 20 mWb. The coefficient of coupling is
A.	1
B.	0.1
C.	0.33
D.	0.67
Answer» E.

Discussion

2580.	In following circuit, steady state is reached with S open, S is closed at t = 0, the current I at t = 0+ is given by
A.	9 &ohm;
B.	6 &ohm;
C.	7 &ohm;
D.	10 &ohm;
Answer» D. 10 &ohm;

Discussion

2581.	When a function Z(s) having a pole at infinity is realized, we get
A.	a capacitance in series
B.	a resistance in series
C.	an inductance in series
D.	a resistance or inductance in series
Answer» D. a resistance or inductance in series

Discussion

2582.	In the circuit shown in figure the inductor current and capacitor voltage are given at a time t. At this instant i is __________ A and is __________ A/sec.
A.	-5 A, 10 V
B.	5 A, 50 V
C.	2.5, 25
D.	0,
Answer» B. 5 A, 50 V

Discussion

2583.	For an RC admittance function Y, the slope dY/d
A.	is positive
B.	is negative
C.	may be positive or negative
D.	0
Answer» B. is negative

Discussion

2584.	A network has only independent current sources and resistance. If values of all resistors are doubled, the values of node voltages
A.	will become half
B.	will remain unchanged
C.	will become double
D.	cannot be determined unless circuit configuration and values of resistors are known
Answer» D. cannot be determined unless circuit configuration and values of resistors are known

Discussion

2585.	Which of the following is/are correct? The circuit shown in the figure.is reciprocalhas Z11 = 2, Z22 = 2has Z11 = 4, Z22 = 2has Z11 = 0, Z22 = 2 Select the correct answer using the code given below:
A.	1 and 3
B.	1 and 2
C.	1 and 4
D.	3 only
Answer» B. 1 and 2

Discussion

2586.	Which one of the following functions is RC driving point impedance?
A.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/147-1040-1.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/147-1040-2.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/147-1040-3.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/networks-analysis-and-synthesis/147-1040-4.png">
Answer» E.

Discussion

2587.	Force = Electric intensity x current.
A.	True
B.	False
Answer» C.

Discussion

2588.	Which is correct for a transfer function?
A.	The poles and zero must be complex
B.	If the poles and zeros are complex or imaginary, they must be conjugate
C.	If the poles and zeros are complex they must be simple
D.	If a zero is imaginary, it must be simple
Answer» B. If the poles and zeros are complex or imaginary, they must be conjugate

Discussion

2589.	Consider the following statements regarding driving point admittance function It is an admittance of R1 networkPoles and zeros alternate on the negative real axis of planeThe lowest critical frequency is a poleY(0) = 1/3 Which of these statements are correct?
A.	1, 2 and 3
B.	2 and 4
C.	1 and 3
D.	1, 2, 3 and 4
Answer» C. 1 and 3

Discussion

2590.	At very low temperatures, semiconducting materials behave as insulators.
A.	True
B.	False
Answer» B. False

Discussion

2591.	A nickel cadmium cell is an alkaline cell.
A.	True
B.	False
Answer» B. False

Discussion

2592.	Current in a 2H inductance in 10e-t A. Admittance of the inductor is
A.	-0.5 mho
B.	0.5 mho
C.	5 mho
D.	10 mho
Answer» B. 0.5 mho

Discussion

2593.	In liquids charge carriers are electrons only.
A.	True
B.	False
Answer» C.

Discussion

2594.	A function f(t) = k eat is __________ for (a > 0).
A.	stable
B.	unstable
C.	marginal
D.	none
Answer» C. marginal

Discussion

2595.	With a line charge along z-axis the field intensity is E = ; which of the following figure shows an exact field distribution?
A.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-758-66-2.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-758-66-3.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-758-66-4.png">
D.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/2-758-66-5.png">
Answer» E.

Discussion

2596.	The dual transform of the given network as
A.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/3-07-88-1.png">
B.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/3-07-88-2.png">
C.	<img src="/_files/images/electronics-and-communication-engineering/exam-question-papers/3-07-88-3.png">
D.	none of the above
Answer» D. none of the above

Discussion

2597.	The following statements are true with respect to "Cascode Amplifier". The reduction in h12 and Miller capacitance result in negligible reverse internal feedback. A's is large loads cannot be connected. As a narrow band amplifier, it provides small range of c is reduced. As a narrow band amplifier it provides small range of frequencies parameters the effect of c reduces.
A.	only 1
B.	only 1 and 4
C.	only 2 and 4
D.	only 1 and 3
Answer» C. only 2 and 4

Discussion

2598.	For a given transfer function: Damping ratio is:
A.	0.707
B.	0.695
C.	1.414
D.	0.798
Answer» B. 0.695

Discussion

2599.	If the open-loop transfer function is a ratio of a numerator polynomial of degree 'm' and a denominator polynomial of degree 'n', then the integer (n - m) represents the number of:
A.	breakaway points
B.	unstable poles
C.	separate root loci
D.	asymptotes
Answer» E.

Discussion

2600.	A uniform plane wave in the free space is normally incident on an infinitely thick dielectric slab (dielectric constant r = 9). The magnitude of the reflection coefficient is
A.	0
B.	0.3
C.	0.5
D.	0.8
Answer» D. 0.8

Discussion

Explore topic-wise MCQs in Engineering.

Assertion (A): The impedance of a series resonant circuit is minimum at resonance.Reason (R): Resonance condition implies unity power factor condition.

The following circuit resonates at

A steel bar needs 1200 AT to magnetise it. The voltage that must be applied to the magnetising coil of 100 turns and 10 &amp;ohm; resistance is __________ volt.

Poor power factor

A reactance function is always a quotient of

The Z parameter of the following T-network is

In figure the effective resistance faced by voltage source is

For a series circuit of R and variable XL the admittance locus is

Assertion (A): In drawing an electric circuit analogous to a mechanical circuit, spring is replaced by capacitance.Reason (R): The behaviour of a spring and capacitor are similar.

In ZRC (s) = constant at s = 0, the last element in first Foster cauer realization is

Norton's equivalent circuit

A 3 phase balanced supply feeds 3 phase unbalanced load. Power supplied to the load can be measured by using 2 wattmeterone wattmeter3 wattmeter Which of the above statements is correct?

In the circuit shown in figure, for different values of R, the values of V and I are given. Other elements remaining the same. when R = , V = 5 volt R = 0, I = 2.5 AR = 3 &amp;ohm;, the value of V is given by

In figure, E = 1 V (rms value). The average power is 250 mW. Then phase angle between E and I is

A current increasing at the rate of 1 A/s is passed through 1 F capacitor. At t = 0, i = 0. The charge stored after 1 second is

In figure, the effective resistance across AB is

For the ladder network of figure, open circuit driving point impedance at port 1 =

In the circuit of figure the current through 3 &amp;ohm; resistance at t = 0+ is

For a high pass filter, = p in attenuation band.

The electrochemical equivalent of a material

The time constant of the capacitance circuit is defined as the time during which voltage

When a current flows through a coil of insulated wire, the coil shows the properties of a magnet.

In a series RLC circuit for lower frequency power factor is __________ .

Assertion (A): Charge is dual of flux.Reason (R): Short circuit is dual of open circuit.

The shot circuit admittance matrix of a two port network is

A choke coil of resistance R and inductance L is shunted by capacitor C. The dynamic resistance is

A parallel ac circuit in resonance will

Assertion (A): If Z1(s) and Z2(s) are positive real then Z1(s) + Z2(s) as well as 1/Z1(s) and 1/Z2(s) are positive real.Reason (R): The poles of a positive real function are real or occur in conjugate pairs.

In an unloaded transformer, the fluxes limiting the primary and secondary are 30 mWb and 20 mWb. The coefficient of coupling is

In following circuit, steady state is reached with S open, S is closed at t = 0, the current I at t = 0+ is given by

When a function Z(s) having a pole at infinity is realized, we get

In the circuit shown in figure the inductor current and capacitor voltage are given at a time t. At this instant i is __________ A and is __________ A/sec.

For an RC admittance function Y, the slope dY/d

A network has only independent current sources and resistance. If values of all resistors are doubled, the values of node voltages

Which of the following is/are correct? The circuit shown in the figure.is reciprocalhas Z11 = 2, Z22 = 2has Z11 = 4, Z22 = 2has Z11 = 0, Z22 = 2 Select the correct answer using the code given below:

Which one of the following functions is RC driving point impedance?

Force = Electric intensity x current.

Which is correct for a transfer function?

Consider the following statements regarding driving point admittance function It is an admittance of R1 networkPoles and zeros alternate on the negative real axis of planeThe lowest critical frequency is a poleY(0) = 1/3 Which of these statements are correct?

At very low temperatures, semiconducting materials behave as insulators.

A nickel cadmium cell is an alkaline cell.

Current in a 2H inductance in 10e-t A. Admittance of the inductor is

In liquids charge carriers are electrons only.

A function f(t) = k eat is __________ for (a &gt; 0).

With a line charge along z-axis the field intensity is E = ; which of the following figure shows an exact field distribution?

The dual transform of the given network as

For a given transfer function: Damping ratio is:

If the open-loop transfer function is a ratio of a numerator polynomial of degree 'm' and a denominator polynomial of degree 'n', then the integer (n - m) represents the number of:

A uniform plane wave in the free space is normally incident on an infinitely thick dielectric slab (dielectric constant r = 9). The magnitude of the reflection coefficient is

A steel bar needs 1200 AT to magnetise it. The voltage that must be applied to the magnetising coil of 100 turns and 10 &ohm; resistance is __________ volt.

In the circuit shown in figure, for different values of R, the values of V and I are given. Other elements remaining the same. when R = , V = 5 volt R = 0, I = 2.5 AR = 3 &ohm;, the value of V is given by

In the circuit of figure the current through 3 &ohm; resistance at t = 0+ is

In the circuit shown in figure the inductor current and capacitor voltage are given at a time t. At this instant i is A and is A/sec.

A function f(t) = k eat is __________ for (a > 0).