ece ntl end term paper 1

7/28/2019 ECE NTL End Term Paper 1

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UNIT 1

1.A delta connection contains three impedances of 60each. The impedances of

equivalent star connection will be

(A) 15 each. (B) 20 each.

(C) 30 each. (D) 40 each.

2.To calculate Thevenins equivalent value in a circuit

(A) all independent voltage sources are opened and all independent current

sources are short circuited.

(B) both voltage and current sources are open circuited

(C) all voltage and current sources are shorted.

(D) all voltage sources are shorted while current sources are opened.

3.The z-parameters of the shown T-network at Fig.1 are given by

(A) 5, 8, 12, 0

(B) 13, 8, 8, 20

(C) 8, 20, 13, 12

(D) 5, 8, 8, 12


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4.The equivalent inductance of Fig.2 at terminals 1 1 is equal to

(A) L1 +L2+ 2M

(B) L1 +L2 -2M

(C) L1 L2

(D) L1- L2 +2M

5.The relation between R1 and R2 for the given symmetrical lattice attenuator shown

inFig.3 is

6.c


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7.Z11 parameter is

.(a)11 (b)12 (c)13 (d)14

8.For a 2-port network, the output short circuit current was measured with a 1V

source at the input. The value of the current gives

(A) h12(B) y12

(C) h21(D) y21

9.For a two port reciprocal network, the three transmission parameters are given by

A = 4,B = 7 and C = 5. The value of D is equal to

(A) 8.5 (B) 9

(C) 9.5 (D) 8

10.If the given network is reciprocal, then according to the reciprocity theorem

(A) y21y12 (B) y22 y12

(C) y11y12 (D) y11 y22

11.For a linear passive bilateral network

(A) h21h12 (B) h21 h12

(C) h12g12 (D) h12 g12

12.A constant voltage source with 10V and series internal resistance of 100 ohm is

equivalent to a current source of

(A) 100mA in parallel with 100 ohm.

(B) 1000mA in parallel with 100 ohm.

(C) 100V in parallel with 10-ohms.


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(D) 100mA in parallel with 1000 ohm.

13.In a two terminal network, the open circuit voltage at the given terminal is 100V

and the

short circuit at the same terminal gives 5A current. If a load of 80 resistance is

connected at the terminal, the load current is given by

(A) 1Amp (B) 1.25 Amp

(C) 6 Amp (D) 6.25 Amp

14.Given VTH = 20V and RTH = 5_, the current in the load resistance of a network,

(A) is 4A (B) is more than 4A.

(C) is 4A or less (D) is less than 4A.

15.A

16.A delta connection contains three impedances of 60_each. The impedances of

the equivalent star connection will be

(A) 15_each. (B) 20_each.

(C) 30_each. (D) 40_each.

17.If VTH and RTH are the Thevenins voltage and resistance and RL is the load

resistance, then Thevenins equivalent circuit consists of

(A) series combination of RTH,VTH and RL .

(B) series combination of RTH and VTH .

(C) parallel combination of RTH,VTH and RL .

(D) parallel combination of RTH and VTH .

18.Superposition theorem is not applicable in:


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(A) Voltage responses (B) Power responses(C) Current responses (D)All the three

19.The condition AD-BC = 1 for a two port network implies that the network is

a) Reciprocal network

b) Lumped element network

c) Loss less network

d) Unilateral element network

20Two port network are connected in cascade, the combination is to be represented

as a single two port network , the parameters of the network are obtained by

multiplying the individuals

a) Z parameter matrix

b) H parameter matrix

c) Y parameter matrix

d) Transmission parameter matrix

21.For two port network to be reciprocal

a) Z11 = Z22

b) Y21 = Y12

c) H21=-h12

d) AD BC =0.

22.Of the two methods of loop and node variable analysis

(A) loop analysis is always preferable.

(B) node analysis is always preferable.

(C) there is nothing to choose between them.

(D) loop analysis may be preferable in some situations while node analysis may be


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preferable in other situations.

23.For an ideal transformer,

(A) both z and y parameters exist.

(B) neither z nor y parameters exist.

(C) z-parameters exist, but not the y-parameters.

(D) y-parameters exist, but not the z-parameters.

24.B

25.D

26. c

27.The z parameters of the network shown in Fig.6 is B


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28.The value of z22 for the circuit of Fig.1 is:(a)4/11 (b)11/4 (c)4/9 (d)9/4

29. c

30The value ofReqfor the circuit of Fig.1 is

(A) 200 (B) 800

(C) 600 (D) 400


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31.A 2 port network using Z parameter representation is said to be reciprocal if

(A) Z11 = Z22 (B) Z12 = Z21

(C) Z12 =Z21 (D) Z11Z22 Z12Z21 = 1

statement for Q 32 -35

32. Z=D

33 Y.=B


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34 h=B

35. T=D

36. Z=B


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37. Y=D

38. Z=A


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39. Y =B


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40.In Z parameter which one is dependent variable?

(a) v (b)i (c) both (d) none

41If two T section are cascaded then it is easy to get

(a) Z (b) Y (c) T (d) h

42.If two T section are series connected then it is easy to get

(a) Z (b) Y (c) T(d) h

43 Y parameter is easly calculated if two network are in

(a) Series (b) parallel (c)both (d) none.

44.In ABCD parameter input side is

(a)i,v(b)i,i(c)v,v(d)none.

45.The two port network is not reciprocal in there is

(a) dependent source (b) independent source (c)both (d)none

46.small signal analysis is done by

(a) z (b)Y (c) h (d) ABCD

47.kirchoof;s law is valid for

(a) dc (b) AC (c) both (d) none

48.unit of h12 is

(a)v (b)A (c) ohm (d) none.


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49. T section can be changed into pi because T is

(a) delta (b) star (c) bridge (d) all.

50.If the section is L then it is easy to get

(a)Z (b)Y (c) ABCD (d)h.

51.Which one of the following is not a two-port parameter

a) Z-parameter

b) Y-parameter

c) ABCD-parameter

d) K-parameter

52.Which one of the following is dependent variable for z-parameter

a) V1 & V2

b) I1 & I2

c) V1 & I1

d) I2,V1

53.For z-parameter we write V! & V2 in term of

a) I1 , V1

b) I2, V2

c) I1 , I2

d) V2, V1

54.Equation of z-parameter is

a) I1=Z11V1+Z12V2

I2=Z21v1+Z22I2

b) V1=Z11V2+Z12V1

V2=Z21V2+Z22V1

c) V1=Z11I1+Z12I2

V2=Z21I1+Z22I2

d) None


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55.Z-parameter is also called as

a) Short-circuit parameter

b) Open circuit parameter

c) Both a & bd) None

56.Unit of z-parameter is

a) Mhob) Ohm

c) Farad

d) Henery

57.Short-circuit line has resistance value

a) 0

b) c) Both

d) None

58.Open-circuit line has resistance value

a) 0

b) c) Both

d) None

59.Ideal voltage source has ____ internal resistance

a) 0

b) Small

c) d) None

60.Match the following

1) Voltage source a) parallel resistance

2) Current source b) series resistance

a) 1-a 2-bb) 1-b 2-a


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c) Both

d) None

61Open circuit means

a) 0 resistance

b) resistancec) 10

d) All of these

62Mesh analysis based on

a) KCL

b) KVLc) Both

d) None

63. Statement 1, KVL is applied in closed loop only

Statement 2, akgebric sum of all voltage drop in

Closed loop is 0 is the kvl

a) Both are right and 2 is correct explanation of 1

b) Both are right and 2 is not correct explanation of 1

c) Both are individually right

d) Both are wrong

64. In z-parameter , V1 & V2 are dependent variable

2. because in z-parameter we write z in terms of I1 & I2

a) both are right and 2 is correct explanation of 1

b) both are write but 2 is not correct explanation of 1c) Both are individually right

d) Both are wrong

65.-unit of z-parameter is ohm for Z11

2-because in z-parameter

a) 1,2 is right and 2 is correct explanation of 1

b) 1,2 is right and 2 is not correct explanation of 1c) Both are individually right


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d) Both are wrong

67. -the hybrid circuit may be reciprocal

2-input in the hybrid circuit there is no any dependent source , then

must be reciprocal

a) 1 is right and 2 is correct explanation of 1

b) 1 is right and 2 is not correct explanation of 1


d) Both are wrong

68. the z-parameter can be changed into y-parameter

2-the relation between z & y is z=1/y

a) 1,2 is right and 2 is correct explanation of 1

b) 1,2 is right and 2 is not correct explanation of 1


d) Both are wrong

69.Choose the correct statement

a) Two port terminal has always same value

b) Two port network has only 2 port

c) Two port network is always represented by 2

d) Two port network is always represented by y

70.The relation between Z11 and Y11 is

a) Z11=1/Y11

b) Z11=-1/Y11

c) Z11=Y22/d) Z11=-Y22/71. The unit of y-parameter is

a) Ohm

b) Farad

c) Mhu

d) Siemens

71 The relation between Z12 and H12 is given by


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a) Z12=H21/H22

b) Z12=H22/H21

c) Z12=H12/H22

d) Z12=-H12/H22

72 Condition for symmetricity in Z-parameter is

a) Z11=Z12

b) Z11=Y22

c) Z11=-Z22

d) Z11=Z22

72. Match the following

1. Z a/p open circuit

2.Y b/q transmission line

3.ABCD c/R short circuit

4.h d/S hybrid

a) 1-b/p 2-c/q 3-a/R 4-d/s

b) 1-a/p 2-b/q 3-d/R 4-c/s

c) 1-a/p 2-c/r 3-b/q 4-d/s

73. condition of reciprocity means

a) Y12=-Y22

b) Y12=Y11

c) Y12=Y21

d) Y22=Y11

74.condition for reciprocity in ABCD

a) AD-BC=-1

b) AB=CD


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c) AD-BC=1

d) AB=-CD

75.condition for symmetrical in h

a) b) c) d) 76.series connection is best suited for:

a) z

b) y

c) ABCD

d) h

77.cascaded connection is best suited for

a) z

b) y

c) ABCD

d) h

78 if z-parameter is , then ABCD isa) [ ],

b) [ ],

c) [

],


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d) ,

79.relation between h11 and ABCD is

a) h11=B/D

b) h11=A/B

c) h11=A/C

d) h11=D/B

80. When two ABCD parameter related circuit are connected by cascaded then

equivalent ABCD is given by

a) ,=[ ],

b) ,= [ ],[

]

C) ,= [ ],

d) ,= [ ],

UNIT 2

1.A 26 dBm output in watts equals to

(A) 2.4W. (B) 0.26W.

(C) 0.156W. (D) 0.4W.

2.Laplace transform of a unit Impulse function is

(A)s. (B) 0.(C) s e (D) 1.

3.A network function is said to have simple pole or simple zero if

(A) the poles and zeroes are on the real axis.

(B) the poles and zeroes are repetitive.


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(C) the poles and zeroes are complex conjugate to each other.

(D) the poles and zeroes are not repeated.

4.Step response of series RC circuit with applied voltage V is of the form

5.Laplace transform of an unit impulse function is given by

(A) 1(B) -1

(C) 1 s (D) 2 / s

6.A function Hs2s/ s2+ 82 will have a zero at(A) s = j4 (B)Anywhere on the s-plane.

(C) On the imaginary axis. (D) On the origin.

7.Laplace transform of the function 1/2u(t) is

(A) 1 /2s(B) s 2(C) 1/ s 2(D) 2s.

8.

9.The integral of a step function is

(A)A ramp function.(B)An impulse function.

(C) Modified ramp function. (D)A sinusoid function.

10.


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.

11.The necessary condition for driving point function is

a) The real part of all the poles and zeros must not be zero or negligible

b) The polynomial P(s) and Q(s) may not have any missing terms between the

highest and

lowest degree unless all even or odd terms are missing.

c) The degree of P(s) and Q(s) may differ by more than one

d) The lowest degree in P(s) and Q(s) may differ by more than two

12.The necessary condition for transfer function is that

a) The coefficient in polynomial P(S) and Q(s) must be real

b) Coefficient in Q(s) may be negligible

c) complex and imaginary poles and zeros may not conjugate

d) if the real part of pole is zero then that pole must be multiple

13.The system is said to be stable, if and only if

a) all poles lie on right half of s plane

b) some poles lie on right half of s plane

c) all poles does not lie on right half of s plane

d) none of the above

14 The transfer voltage gain is defined as

a)The ratio of transform voltage at one port to current transform at other port.


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b) The ratio of transform voltage at one port to voltage transform at other port.

c) Both a) and b)

d) none of the above.

15 The transform current gain is defined as

a)The ratio of transform current at one port to current transform at other port.

b) The ratio of transform voltage at one port to voltage transform at other port.

c) The ratio of transform current at one port to voltage transform at other port.

d) None of the above.

16.The driving point admittance is defined as

a) The ratio of transform voltage at one port to current transform at other port.

b) The ratio of transform current to voltage transform at same port.

c) The ratio of transfer current at one port to voltage transform at other port.


17. Transfer admittance is defined as

a) The ratio of transform voltage at one port to current transform at other port.

b) The ratio of transform current to voltage transform at same port.

c) The ratio of transform current at one port to voltage transform at other port.


For question 18 & 19 refer same figure.


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18.

19.

20.A network function can be completely specified by:

(A) Real parts of zeros (B) Poles and zeros

(C) Real parts of poles (D) Poles, zeros and a scale factor

21.In the complex frequency s j, has the units of rad/s and has the units

of:

(A) Hz (B) neper/s(C) rad/s (D) rad

22.The following property relates to LC impedance or admittance functions:

(A) The poles and zeros are simple and lie on the j -axis.

(B) There must be either a zero or a pole at origin and infinity.

(C) The highest (or lowest) powers of numerator or denominator differ by

unity.

(D)All of the above.


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23.

24.If a network function has zeros only in the left-half of the s-plane, then it is said tobe

(A) a stable function. (B) a non-minimum phase function.

(C) aminimum phase function. (D) an all-pass function.

25.Zeros in the right half of the s-plane are possible only for

(A) d.p. impedance functions. (B) d.p. admittance functions.

(C) d.p. impedance as well as (D) transfer functions.

admittance functions.

26,An L-C impedance or admittance function:

(A) has simple poles and zeros in the left half of the s-plane.

(B) has no zero or pole at the origin or infinity.

(C) is an odd rational function.

(D) has all poles on the negative real axis of the s-plane.

27.The Laplace-transformed equivalent of a given network will have 5/8F capacitor

replaced by

(A)5/8s (b)8s/5 (c)8/5s (d)5/8


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28A network function contains only poles whose real-parts are zero or negative. The

network is

(A) always stable.

(B) stable, if the j-axis poles are simple.

(C) stable, if the j-axis poles are at most of multiplicity 2

(D) always unstable.

29.

30. D

31. a


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32.

33.

34.

35A stable system must have


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(A) zero or negative real part for poles and zeros.

(B) atleast one pole or zero lying in the right-half s-plane.

(C) positive real part for any pole or zero.

(D) negative real part for all poles and zeros.

36.The Transfer function of the system is used to determine:

a) The output for a given inputb) The type of the systemc) The input for a given outputd) The steady state gain

37. The transfer function of a system is defined as:a) The laplace transform of the impulse response

b) Laplace transform of the step responsec) Laplace transform of the ramp responsed) Laplace transform of the sinusoidal input

38. The transfer function has the main application in the study of __ behavior of the systema) Steadyb) Transientc) Both steady and transientd) None of the above

40. Transfer function of the control system depends ona) Initial conditions of input and outputb) System parameters alonec) Nature of the inputd) Nature of the output

41. The ON-OFF controller is a __ system

a) Linear

b) Non linear

c) Discontinuous

d) Digital

42The impulse function is a derivative of __ function:

a)Parabolic

b) Step

c) Ramp

d) Linear

43 A


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.

44.For system to be stable,roots lie on

a) left side b) right side c)both d)none.

45.poles are the roots of

a) numerator b)denominatorc) both d) none.

46.zeros are the roots of the

a) numeratorb)denominator c) both d) none.

47. The open-loop transfer function of a unity feedback system is

48.Gain is same as

a) admittance b) impedance c)function d)conductance.

49.In communication in system ,signal is generally operates in

a)time domain b)frequency domain c)both d)none.

50.In communication in air ,signal is generally operates in

a)time domain b)frequency domain c)both d)none.

UNIT 3

1.The Characteristic Impedance of a low pass filter in attenuation Band is

(A) Purely imaginary. (B) Zero.

(C) Complex quantity. (D) Real value.


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2.The purpose of an Attenuator is to:

(A) increase signal strength. (B) provide impedance matching.

(C) decrease reflections. (D) decrease value of signal strength.

3.An attenuator is a

(A) Rs network. (B) RL network.

(C) RC network. (D) LC network.

4.All pass filter

(A) passes whole of the audio band.

(B) passes whole of the radio band.

(C) passes all frequencies with very low attenuation.

(D) passes all frequencies without attenuation but phase is changed

5.For a constant K high pass -filter, characteristic impedance Z0 for f < fc is

(A) resistive. (B) inductive.

(C) capacitive. (D) inductive or capacitive

6.Which one of the following is a passive element?

(A)A BJT. (B)An Inductor.

(C)A FET. (D)An Op-amp.

7.An RLC series circuit is said to be inductive if

(A) L 1 C(B) L 1 C

(C) L 1 C (D) L C

8.An ideal filter should have

(A) Zero attenuation in the pass band.

(B) Zero attenuation in the attenuation band.

(C) Infinite attenuation in the pass band.

(D) Infinite attenuation in the attenuation band.


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9.Bridged T network can be used as:

(A)Attenuator(B) Low pass filter

(C) High pass filter(D) Band pass filter

10.The minimum amount of hardware required to make a lowpass filter is

(A) a resistance, a capacitance and an opamp.

(B) a resistance, an inductance and an opamp.

(C) a resistance and a capacitance.

(D) a resistance, a capacitance and an inductance.

11.Which of the following cannot be used active filter?

(a) Diode (b) Triode

(c) Tetrode (d) all.

12. A low pass filter with cutoff frequency fc pass the signal

(a)below (b)above (c) both (d) none.

13A high pass filter with cutoff frequency fc pass the signal

(a)below (b)above (c) both (d) none.

14 If f1 &f2 are the two cut off frequency of bandpass filter then

(a)f1f2(d)all.

15..For a low pass filter o/p at infinite is

(a)1 (b)2 (c)3 (d)0

16.The transfer function of low pass filter is 1/(1+RCs).this is

(a)true (b)false (c)need more data (d) none

17.The transfer function of low pass filter is RCs/(1+RCs).this is



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18.The transfer function of high pass filter is RCs/(1+RCs).this is


19.The filter is used in

(a) reciver (b)camera (c)battery (d)none

20.At fc gain is decreased by

(a)1db (b)2db (c)3db (d)4db

21.At fc gain Amax/1.414

(a)true (b)false (c)need more data (d) none.

22.Butterworth filter may be

(a)LP (b)HP (c)BP (d)all

23.cutoff frequency of low pass filter ig given by fc=1/2RC.statement is

(a)true (b)false (c)need more data (d) none.

24. The decibel is a measure of

(a) power

(b) voltage

(c) current

(d) power level

25When the output voltage level of a filter decreases by 3 dB, its absolute value changes by a factor

of

(a) 2(b) 1/ 2(c) 2(d) 1/2

26. The frequency corresponding to half-power point on the response curve of a filter is known as

(a) cutoff

(b) upper

(c) lower

(d) roll-off

27. In a low-pass filter, the cutoff frequency is represented by the point where the output voltage is

reduced to per cent of the input voltage.

(a) 50

(b) 70.7

(c) 63.2

(d) 33.3

28. In an RL low-pass filter, an attenuation of 12 dB/octave corresponds to ...........dB/decade.

(a) 6


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(b) 12

(c) 20

(d) 40

29. A network which attenuate a single band of frequencies and allows those on either side to pass

through is called ........filter.(a) low-pass

(b) high-pass

(c) bandstop

(d) bandpass

30. In a simple high-pass RC filter, if the value of capacitance is doubled, the cut-off frequency is

(a) doubled

(b) halved

(c) tripled

(d) quadrupled

31. In a simple high-pass RL filter circuit, the phase difference between the output and input voltages

at the cutoff frequency is ....degrees.

(a) 90

(b) 45

(c) 45

(d) 90

32. In a simple low-pass RC filter, attenuation is 3 dB at fc. At 2 fc, attenuation is 6 dB. At

10 fc, the attenuation would be .... dB.0

(a) 30(b) 20(c) 18(d) 12

33. An a.c. signal of constant voltage 10 V and variable frequency is applied to a simple high-pass RC

filter. The output voltage at ten times the cut off frequency would be ............... volt.

(a) 1(b) 5(c) 10 /2(d) 102

34. When two simple low-pass filters having same values of R and C are cascaded, the combined

filter will have a roll-off of ...... dB/decade.

(a) 20

(b) 12

(c) 40

(d) 36

35. An a.c. signal of constant voltage but with frequency varying from dc to 25 kHz is applied to a

high-pass filter. Which of the following frequency will develop the greatest voltage at the output load

resistance?

(a) d.

(b) 15 kHz

(c) 10 kHz

(d) 25 kHz

36. A voltage signal source of constant amplitude with frequency varying from dc to 25 kHz is applied

to a low-pass filter. Which frequency will develop greatest voltage across the output load resistance?

(a) d.c.(b) 10 kHz


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(c) 15 kl

(d) 25 kHz

36. The output of a filter drops from 10 to 5 V as the frequency is increased from 1 to 2 kHz. The dB

change in the output voltage is

(a) 3 dB/decade(b) 6 dB/octave

(c) 6 dB/octave

(d) 3 dB/octave

37 What kind of filter can be used to select a signal of one particular radio station?

a. low pass

b. high pass

c. band pass

d. band stop

38.When the elements of an RLC circuit are both magnitude scaled and frequency scaled, which

quality is unaffected?a. resistor

b. resonant frequency

c. bandwidth

d. quality factor

39.sharpcutoff rate is increased by

(a )higer order s/s(b)lower orders /s(c) both (d)cant change.

40.In k derived filter product of shunt and series impedence is

(a)constant (b)vairy (c)k2(d) k4

41.In m derived filter product of shunt and series impedence is

(a)constant (b)vairy (c)k2(d) k4

42.In k derived filter k is given by

(a)R/C(b)L/C(c)C/L(d)R/L

43.The drawback of k derived filter is attenuation is more,statement is

(a)true (b)false (c) need more data (d)none

44.T.F=RCs/(1+RCs)2.this filter is

(a)1st

order (b)2nd

order (c)3rd

order (d)4th

order

45. Attenuator action on signal is

a) decrease the level b) increase the level c) both d0none.

46.Degree of denominator & numerator of given system is


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a)m,m b)m,n c)n,m d)n,n

47.poles of given system is

a)-3,1/2 b)-2,-3, c)2,3 d)-2,3.

48

.

a)-3,1/2 b)-2,-3, c)2,3 d)-2,3.

49.poles are generally denoted by

a) * b) 0 C)both d)none.

50.Zeros are generally denoted by

a) * b) 0 C)both d)none.

UNIT 4

1.To calculate Thevenins equivalent value in a circuit

(A)all independent voltage sources are opened and all independent current

sources are short circuited.


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(B)both voltage and current sources are open circuited

(C)all voltage and current sources are shorted.

(D)allvoltage sources are shorted while current sources are opened

2.The real part of the propagation constant shows:

(A) Variation of voltage and current on basic unit.

(B) Variation of phase shift/position of voltage.

(C) Reduction in voltage, current values of signal amplitude.

(D) Reduction of only voltage amplitude.

3.In a transmission line terminated by characteristic impedance, Zo

(A) There is no reflection of the incident wave.

(B) The reflection is maximum due to termination.

(C) There are a large number of maximum and minimum on the line.

(D) The incident current is zero for any applied signal.

4.A pure resistance, RL when connected at the load end of a loss-less 100 line

produces a VSWR of 2. Then RL is

(A) 50 only. (B) 200 only.

(C) 50 or 200 . (D) 400 .

5.The reflection coefficient of a transmission line with a short-circuited load is

(A) 0. (B) .

(C) 1.00. (D) 1.0180.

6.The velocity factor of a transmission line

(A) is governed by the relative permittivity of the dielectric.

(B) is governed by the skin effect.

(C) is governed by the temperature.


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(D)All of the above.

7. If '' is attenuation in nepers then

(A) attenuation in dB = / 0.8686. (B) attenuation in dB = 8.686 .

(C) attenuation in dB = 0.1 . (D) attenuation in dB = 0.01 .

8.The characteristic impedances z0 of a transmission line is given by, (where R, L, G,

C are the unit length parameters)

(A) R jL/G jC(B) R jLG jC

(C) R j L/G j C2 (D) 1/ 2 R jL / G jC

9.Voltage Standing Wave Ratio (VSWR) in terms of reflection coefficient is given

10.If Zoc120and Zsc30, the characteristic impedance is

(A) 30(B) 60

(C) 120(D) 150

The reflection coefficient of a line is 1. The line is

(A) Open circuited.(B) Short circuited.

(C) Terminated in Zo.(D) Of infinite length

12.If a transmission line of length less than 4 is short circuited, it behaves as

(A) Pure capacitive reactance. (B) Series resonant circuit.

(C) Parallel resonant circuit. (D) Pure inductive reactance.

13.A line becomes distortion less if

(A) It is properly matched (B) It is terminated into Zo


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(C) LG = CR(D) LR = GC

14.Double stub matching eliminates standing waves on the

(A) Source side of the left stub (B) Load side of the right stub

(C) Both sides of the stub (D) In between the two stubs

15.If ZOC 100and ZSC 64, the characteristic impedance is

(A) 400(B) 60

(C) 80 (D) 170

A (3 + 4j) voltage source delivers a current of (4 + j5) A. The power delivered by

the source is

(A) 12 W(B) 15 W

(C) 20 W (D) 32 W

17.Consider a lossless line with characteristic impedance Ro and VSWR = S. Then

the impedance at the point of a voltage maxima equals

(A)SR0(B) R0/S

(C) s2R0(D) R0

18.A symmetrical T network has characteristic impedance Zoand propagation

constant .Then the series element Z1 and shunt element Z2 are given by

19.Input impedance of a short-circuited lossless line with length 4 is

(A) Zo(B) zero

(C) infinity(D) 2

20.For a transmission line, open circuit and short circuit impedances are 20_and 5_.

The characteristic impedance of the line is(A) 100 (B) 50


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(C) 25 (D) 10 .

21.If K is the reflection coefficient and S is the Voltage standing wave ratio, then B

22 B

23. B

24.In a series resonant circuit, the resonant frequency will be

(A) Geometric mean of half power frequencies.

(B)Arithmetic mean of half power frequencies.

(c) Sum of half power frequencies(d) Difference of half power frequencies.

25Total reflection can take place if the load is:

(A) 0 (B)

(C) 0 and (D) Zo

26.The characteristic impedance of a distortion less line is:

(A) Real(B) Inductive

(C) Capacitive (D) Complex

27.A transmission line works as an

(A)Attenuator(B) LPF

(C) HPF (D) Neither of the above


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28.Radio frequency are in the range of

a) KHZ

b) MHZ

c) GHZ

d) All

29.The primary constant of TX. Line is

a)R b) G c) L d)all

30. secondary constant of TX line is

a)R b) G c) none d)all

31.Wavelength is measured in

a) m b)sec c)HZ d)f

32.open circuit line the line whose o/p is

a) open b) short. C) both d)matched.

33.short circuit line is the line whose o/p is

a) open b) short. C) both d)matched.

34.open circuit line the line whose i/p is

a) open b) short. C) both d)none

34.short circuit line is the line whose i/p is

a) open b) short. C) both d)none.

35. Loss is generally measured in

a) db b) HZ c) f d)ohm..

36.A two-port network is defined by the relation

I=5V1+3V2

I2=2V1-7V2The value of Z12 is

A. 3

B. -3

C. 3/41D. 2/31


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37The Z-transform of x(K) is given by

x(Z)= {(1-e-T)z-1} / {(1-z-1)(1-e-Tz-1)}

The initial value of x(0) is

A. Zero

B. 1

C. 2D. 3

38 Consider the following statements with reference to the phase plane:

a. They are general and applicable to a system of any order.

b. Steady state accuracy and existence of limit cycle can be predicted.

c. Amplitude and frequency of limit cycle if exists can be evaluated.

d. Can be applied to discontinuous time system.

39.Which of the above statements are correct

A. 1,2,3 and 4

B. 2 and 3 only

C. 3 and 4 only

D. 2,3 and 4 only

40.If reflection coefficient for voltage be 0.6, the voltage standing wave ratio(VSWR) is

A.0.66

B.4

C.1.5

D.2

41.In a _________ transmission line, the reflection coefficient domain is a circle of

unitary radius.

a. Lossy

b. Lossless

c. None of these

d. Cannot say

42.A transmission line is specified in terms of _________.

a. R, G,L

b. G, L,C

c. R, G, L,C


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d. None of these

43.In the case of a lossless transmission line _________.

a)LC=

b)Both (a) and (b)

c) None of these

d)LC =RC

44.Velocity of propagation in a lossless transmission line is given as ___D______.

45Conductance per unit length of a coaxial transmission line is given as ___________.

46.In planar transmission lines, C= _________.

e. b/d

f. d/b

g. b/d


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h. None of these.

47.In a microstrip line, there is _________metal strip over the substrate.

i. A thin

j. A thick

k. No

l. None of these

48.Characteristic impedance Zo = __C_______.

49.In a fully lossless line, = _________.

m.0

n. 1

o.

p. None of these.

50.In a distortionless line, attenuation constant is frequency _________.

q. Dependent

r. Independent

s. None of these


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t. Cannot say

51.Adistortionless line has _________.

u. Non-vanishing attenuation constant

v. Constant velocity

w. Constant real characteristic impedance

x. All of these

52.Voltage reflection coefficient is the ratio of _________ wave to _______ wave.

y. Incident, reflected

z. Reflected, incident

aa.Incident, absorbed

bb.Absorbed, incident

53.In a quarter-wave transformer, input impedance is equal to _________.

54. For transmission lines the standing wave ratio is the ratio of(A) maximum voltage to minimum voltage(B) maximum current to minimum voltage(C) peak voltage to rms voltage(D) maximum reactance to minimum reactance.

55.. In a transmission line following arc the distributed constants(A) resistance and inductance only(B) resistance, inductance and capacitance(C) resistance, inductance, capacitance and short conductance.

56. The disadvantage of transmission lines as compared to cables is(A) exposure to lightening(B) exposure to atmospheric hazards like smoke, ice, etc.


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(C) inductive interference between power and communication circuits(D) all of the above.

57. In transmission system a feeder feeds power to(A) service mains

(B) generating stations(C) distributors(D) all of the above.

58.. Which of the following statements is incorrect ?(A) As the temperature rises the tension in the transmission line decreases(B) As temperature rises the sag in transmission lines reduces(C) Tension and sag in transmission lines are complementary to each other.

59. Boosters are basically(A) inductors

(B) capacitors(C) transformers(D) synchronous motors.

60. Conductors for high voltage transmission lines are suspended from towers(A) to reduce clearance from ground(B) to increase clearance from ground(C) to reduce wind and snow loads(D) to take care of extension in length during summer.

61. When alternating current passes through a conductor(A) it remains uniformly distributed throughout the section of conductor(B) portion of conductor near the surface carries more current as compared to thecore(C) portion of conductor near the surface carries less current as compared to thecore(D) entire current passes through the core of the conductor.

62Skin effect results in(A) reduced effective resistance but increased effective internal reactance of theconductor

(B) increased effective resistance but reduced effective internal reactance of. theconductor(C) reduced effective resistance as well as effective internal reactance(D) increased effective resistance as well as effective internal reactance.

63. Skin effect depends on(A) size of the conductor(B) frequency of the current(C) resistivity of the conductor material(D) all of the above.

64. Skin effect is proportional to(A) diameter of conductor


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(B) (diameter of conductor)1/2(C) (diameter of conductor )2(D) (diameter of conductor )2.

65. In overhead transmission lines the effect of capacitance can be neglected when

the length of line is less than(A) 200 km(B) 160 km(C) 100 km(D) 80 km.

66 The disadvantage of constant voltage transmission is(A) short circuit current of the system is increased(B) load power factor in heavy loads(C) large conductor area is required for same power transmission(D) air of the above.

67. Which of the following regulation is considered to be the best(A) 2%(B) 30%(C)70%(D) 98%.

68. The characteristic impedance of a transmission line depends upon(A) shape of the conductor(B) surface treatment of the conductors(C) conductivity of the material(D) geometrical configuration. of the conductors.

69. In case the characteristic impedance of the line is equal to the load impedance(A) all the energy will pass to the earth(B) all the energy will be lost in transmission losses(C) the system will resonate badly(D) all the energy sent will be absorbed by the load

70. For a properly terminated line(A) ZR=ZO

(B) Z/R > ZO(C) ZR < ZO(D) ZR =Z0 = 0.

ece ntl end term paper 1

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